Mindscape Ask Me Anything, Sean Carroll | August 2026

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1:01Hello, everyone. Welcome to the August 2026 Ask Me Anything edition of the Mindscape podcast. I'm your host, Sean Carroll. I know the news that is on everyone's mind, and it's certainly on mine. Maybe it's not on yours, but you think it's on mine, and you're correct. But LeBron James, who is in the conversation for one of the best basketball players of all time, has agreed to join the Philadelphia 76ers, who are by acclamation the greatest basketball team of all time, and at least my personal favorites.

1:31So this is big news, and everyone wants to know. There's been several mentions in the AMA questions this month. You know, what do you think about LeBron joining the Sixers? And the answer is, I am thrilled. I think that this is amazing. I think he's basically a perfect fit for the team. I think the team is basically a perfect fit for him. LeBron, you know, is getting up there. He is dead-ass old. There's just no question about that. LeBron is pushing 42, I think he'll be, this season.

2:02But he was super productive last year, playing at an all-star level, and no reason to think that he can't do that again this year. And there's been some moaning out there in the internet corners that I listen to for basketball news and gossip that there's almost too many good players on the Sixers right now. Literally, if all the players that they have, now they also have Jalen Brown, who they acquired in a trade from the Celtics, with Joel Embiid, Tyrese Maxey, Vijay Edgecombe.

2:36In pure talent terms, this is one of the best starting fives in the history of the NBA. Now, pure talent terms don't matter if they don't gel, if they get injured, if their styles get in the way, if there's personality conflicts. There's many things that could go wrong. But for the moment, I'm going to choose to be optimistic. I think that what a lot of people miss is that LeBron, even though he has scored more points than any other NBA basketball player ever, takes some of his greatest joy from being a facilitator and a passer.

3:07When he joined the NBA, he said he wanted to be more like Magic Johnson than Michael Jordan. And that is exactly what the Sixers need. And he plays a position, which was by far the Sixers' weakest position. He'll have multiple great players to pass to on any one night, any one of the starting five can score 30 points. Everyone can take turns, and I see no reason why everything won't be great. But I don't want to bore the people who are listening who are not basketball fans. I just want to say one little philosophical point about this.

3:37I was visiting Santa Fe Institute and talking to Jeffrey West, former Mindscape guest, and I didn't know this, but Jeffrey is a huge football fan in the sense of he's British. Soccer is what we would call it here in the United States. He was following very carefully. England's journey in the World Cup this year, and he kind of had very strong feelings for how they were actually playing better. No, they were playing worse than they were able to, but doing better than they should have just through sort of luck and randomness,

4:08and then their luck ran out in the semifinals when they lost to Argentina. But anyway, so we were bonding about this because, you know, we both agreed, like, people don't know how much of our lives are spent thinking and caring about sports. He's a fan of Tottenham Hotspur. I am not very knowledgeable about football slash soccer, but, and I know nothing about Tottenham Hotspur. I know who they are, but I don't know any of their history or anything like that. But nevertheless, I could feel and appreciate all the emotions that he was expressing

4:38in thinking about how his fandom expressed itself over the years. Look, Jeffrey is getting up there in years himself. We were talking about basketball a little bit. He says, I know nothing about basketball, but I do remember, you know, watching once and seeing this huge guy just dominating and being very impressed with him. And I was trying to guess. I'm like, was it Shaquille O'Neal? And he goes, oh, no, before that. And then someone says, Wilt Chamberlain. Yes, that was it. So that was a while ago, since Wilt retired in the early 70s.

5:09The point is that I didn't need to know details about Tottenham Hotspur to get where Jeffrey was coming from any more than he needed to know details about the Philadelphia 76ers. And we agreed, you know, it's irrational. Maybe irrational is not the word. It's non-rational to love a sports franchise in this way. If you had been born in different circumstances, you would have loved some other sports franchise, and that's fine. But the irrationality or non-rationality

5:40is part of it, I think. This is the place I've come to in thinking about it. When people ask me how I feel about LeBron James joining the Sixers, it could be amazing, right? They could be one of the best NBA teams of all time, or it could all fall apart, as I've already said. But here's the thing. We don't know. None of us is Laplace's demon, right? What LeBron James joining the Philadelphia 76ers represents is hope. It's the prospect of something amazing happening.

6:14You know, when you watch a TV show or watch a movie, you don't know what's going to happen, but someone does. Someone made the movie, right? But when you watch a sporting event, you don't know what is going to happen out there, and that is part of the joy. I think a lot of modern sports fans sort of miss the point of the experience by trying to pretend that they're general managers and coaches rather than just rooting for their teams and hoping for the best. If your team plays in a league where there's only going to be one champion at the end of the year,

6:45most teams' fans are going to end up the season disappointed in some sense. But you're allowed to begin the season very optimistic, and that is how I choose to approach things. So LeBron represents hope to us, hope that the Sixers can finally get over the hump and win one, that Joel Embiid's career will be vindicated, or who knows? We just don't know for sure, but we can root for them. We can take pleasure in the anticipation of victory,

7:18and then we'll have to deal with it if we don't get it. So non-rational or not, I think that the more I think about it, the happier I am that there exists something like sports fandom, and there's different versions of that for different people. That's fine. There's nothing special about sports. But the stakes are low. It doesn't really matter who wins, right? But the emotional investment is very, very high, and that's a good kind of situation to have. Speaking of emotional investments being high, the Ask Me Anything questions

7:49here for the Mindscape podcast are offered up by our Patreon supporters. If you want to be a Patreon supporter, you can join up by coming to patreon.com slash Sean M. Carroll and pledging a little bit of support. And then you get to ask the questions. Once in your life, you get a priority question that I will do my best to answer. And you also get ad-free versions of the podcast, and you get to chat with other Patreon supporters in the Patreon comment section, which is a lot of fun. So I always appreciate that.

8:19Appreciate everyone who listens to Mindscape. Let's go. Anonymous says, My recently five-year-old son is a curious soul and frequently asks me questions about almost everything he sees. One of the common patterns of questioning is,

8:50What is that? Followed by, Why is it that thing? After I answer. I don't want to discourage him by pointing out the category error, so I usually either describe what the thing in question does or how it got there. However, this happens often enough that I wonder if there are any other ways I might be able to answer, to approach this type of question. Do you have any ideas? You know, I don't think that you want to be overly philosophically fastidious when you're talking to five-year-olds. When someone says, Why is something this rather than that,

9:20especially when they're a five-year-old and they haven't understood the basic map of reality, what you want to do is not give the answer that is most technically correct, but rather the answer that is most satisfying the particular itch that they're attempting to scratch by asking the question in the first place. I mean, they might just be being annoying. Kids do that sometimes, right? Like, they just want to keep asking the question. But what is it that would make them happy? You know, why is a tree a tree?

9:54You know, what even possible answer could you get for that? But you could use that as an excuse to talk about the ecosystem and why there are plants and animals and what it means to be that way. Eventually, if you really do have someone who is just pushing you and won't let go, you will bottom out and you just have to say things are like that and everyone eventually learns to put up with that kind of answer. Philip Rissius says, How is the damage on academia by political institutions panned out so far?

10:26Is it still a slow-moving car wreck waiting to happen or are effects becoming visible? The car wreck is not at all slow-moving and the effects are super visible and have been visible for a while now. You know, I hope people understand this. You know, sometimes you have complaints politically or whatever because you think something bad is going to happen, but maybe you can avoid it. This is already happening. There has been absolutely devastating and irreversible damage to science

10:58in the United States and to academia in the United States. And again, it's been happening for two years now. As soon as cuts came in to overhead, as I described in a sort of bonus podcast a year and a half ago or whatever, you know, the government decided that universities were just taking too much money for their own use rather than putting them to the purposes of the grants that were being offered, etc. What that means is that every university

11:30suddenly has a huge budget cut, okay? And that's real and that's happened. And what does that mean? Well, they're not going to fire professors or things like that, but they're going to let other people go. So administrative help throughout the university has been decreased. People retire and don't get replaced. Universities are looking everywhere they can for places to save money, which is not always an encouraging environment to be in. You know, this year I hired a postdoc

12:00through what is usually a fairly standard procedure. I had money to do it and it took forever. We didn't get the official offer letter out until July, even though the offer was made back in December or January. And it's just because our administration has been cut to the bone, okay?

12:20Students and postdocs and faculty members from other countries who ordinarily would look at it as a wonderful opportunity to come to the United States are saying, no, we don't want to do that now because the United States is a disaster area. We don't want to go. We had a search for a new theoretical physicist at Johns Hopkins last year that we went through all of it. I was on the committee to find the person, etc. We got a great candidate canceled at the end because we don't have the money to do that. And it's just getting worse.

12:51People's NSF grants and DOE grants are just being cut or slow-played so that, you know, you are supposed to get money but the money just never appears. So, of course, there is momentum and people are trying to be resilient so people try to keep things going but there's no question. It is absolutely hurting very badly already. And I do think that despite the fact that things are happening right now and it's hurting badly already, the real effects will be very long-lasting.

13:21There's a loss of trust like why would you think that you could keep up a research program here in the United States if every four years you might elect a crazy person who would just cut it to the bone? There's weird political worries that, you know, if you as a faculty member say the wrong things, the government will target you. It's just terrible. The whole wonderful thing that we've built up over a couple hundred years in making the United States a leader in the world of research and scholarship

13:51has been more or less undone and the effects are going to be felt for many, many, many years to come.

13:59Allen, A-L-E-N, says, can you clarify why Boltzmann brain blindness constitutes a genuine problem for cosmology rather than simply an epistemic dead end? It seems to me that from every angle the only rational way to pursue science is to assume that we are ordinary observers produced by the universe's original low-entropy evolution. If we use empirical evidence or logical reasoning to conclude that we are probably Boltzmann brains, that conclusion immediately undermines the reliability of the entire evidentiary and reasoning chain that produced it. The proposition, therefore,

14:31seems cognitively self-defeating. There is no stable standpoint from which we can both accept the Boltzmann brain conclusion and continue treating scientific reasoning as truth tracking. Even if our eventual best model, whether lambda CDM or otherwise, implied that fluctuation observers vastly outnumber ordinary observers, wouldn't the only rational response still be to assume that we are among the ordinary observers? Under the alternative assumption, doing science seems futile by definition. I'm with you there right up until the end. I just don't think

15:02that you're dealing with the problem correctly. You're diagnosing the problem in a perfectly fair way. If we were Boltzmann brains, we would have all these epistemic issues. We would not be able to justify our beliefs in the conclusions we were reaching. That does not mean that if our best conclusion that we reached was a prediction that people like us, literally like us, forget about the brains floating in space, okay? People exactly like you are overwhelmingly likely

15:33to be random fluctuations from an initially higher entropy state. You can't just say, but I'm not one of them. That's not a loud move. That's a God's eye view that you don't have any access to. The best you can do in that situation is to accept what your theory tells you and understand and understand that you have been led to a theory that is self-undermining and you are screwed. There's really nothing you can do. You should, if you're playing fair,

16:04you should take at face value the predictions of your theory. You're not allowed to say, well, I've developed a really good theory. It makes this prediction, but I don't like it, so I'm going to just sort of pretend that I'm not one of the ones who is susceptible to that prediction. Happily, there is a perfectly good way out, which is to develop a better theory. If it were the case that the universe was set up so as to be inevitably self-undermining or unintelligible to human beings,

16:35that would be too bad, right? That would absolutely be a disaster and, you know, we couldn't do science anymore. But there's no reason to think that. There's no reason to think that we have to live in a universe where most people like us are random fluctuations out of the random chaos around us. We can do better. That's what I do. That's what we try to do as scientists. Build models of the universe that are compatible with the data and do not have this problem.

17:05That is the way out. Build cosmologies where Boltzmann brains are not dominating the set of people who are consistent with the data that we have.

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20:02Karmaria says, Do you think that shows like Barry and Breaking Bad are realistic in terms of how far people will go given a set of conditions? Has your research in philosophy, physics, and other fields led you to believe that there is a set of human behaviors that are good versus bad? You know, I don't know about my research, but, you know, I don't, even when I do philosophy, I don't do moral philosophy or psychology. But I, one of the reasons why shows like Barry and Breaking Bad are good and interesting

20:32is that they are entirely realistic. I mean, look at history. Look at the set of people who've done things throughout history. A lot of them have broken bad. A lot of them have done really, really terrible things. And usually it's not like the comic books, right? It's not like they're self-proclaimed supervillains. People don't think of themselves as evil or doing bad. They have justifications for what they're doing. And I think that, I know a lot more people have seen Breaking Bad than seen Barry, but Breaking Bad

21:03is a great example of, you know, the protagonist, Walter White, is bad, okay? Some people, some people root for him, but he is bad. He's also sympathetic. That's one of the brilliant things about the show is that it makes you understand why he would become bad. You understand his motivations. I think that this is what is happening with Barry also. For people who haven't seen it,

21:34Bill Hader, who is most famous as a comedian on Saturday Night Live, started this show which was supposed to mix comedy and drama, okay? And my suspicion, and this is not based on any inside information whatsoever, I'm just guessing that what happened is, you know, they started this show with the idea that it would be kind of a fish-out-of-water comedy show with some dramatic elements where this guy who was a hired assassin, ex-military, hitman for hire, decides he doesn't want

22:04to live that life anymore and he starts taking acting lessons and, you know, moves to Hollywood, okay? There's a lot of rich material you could mine for comedy in there, but I suspect that what happened is they just got interested in the question of but, okay, what would really happen? Like, forget about the comedy. The comedy is still there, but in the later seasons it gets really dark, this show, because the character of Barry, who is brilliantly played by Bill Hader, is very self-justifying,

22:37right? Like, he kills a lot of people and he always thinks he has a good reason to do it. Sometimes he thinks the reason is just he's earning a living, but other times, you know, he's like, well, I had to kill that person, otherwise they would have told on me and would have gone to jail. And, you know, to him, that's a perfectly good justification for what he does and it's fascinating for those reasons. So, I don't think that there is objectively out there in the world criteria by which we judge things to be good or bad, but subjectively in the world of human beings, yeah, there absolutely are

23:07sets of human behaviors that I'm very happy, willing to label good versus bad and both of these shows are examples of sympathetic characters doing really, really bad things. Stephen Slayton says, Star formation 101. We're told that the primordial plasma condensed into hydrogen about 400,000 years ago. Old, sorry, not ago. And also that the iron nucleus is at the bottom of the energy curve. You can get energy by splitting a large nucleus like an atomic bomb

23:38or fusing small ones like a hydrogen bomb, but there's no iron bomb. So why isn't the universe made of iron? Just wait. That's the direction we're moving in, right? You know, it is true. So if you don't think about gravity, don't think about cosmology, just think about atoms and nuclei. What is the lowest energy state that you can take some set of baryons, right? Baryons are the protons and the neutrons that we use to make atomic nuclei.

24:09Their lowest energy state is iron. That's the highest point in the curve of binding energy. The most binding energy, which means the lowest total energy for the nucleus itself. But it takes work to get there, right? Like, I can't just take, I don't know, a jar of hydrogen and smush it together and make iron. It turns out to be harder than you think. We can't even make helium very effectively, right? This is the barrier that we find when we try to do nuclear fusion.

24:39hydrogen as an energy source. We would love to be able to do it. Turns out to be harder than it looks, right? Because there are potential barriers. It's hard to squeeze two protons close enough to fuse to make a deuteron. And that's perfectly consistent with the laws of physics. Just because something is the ultimate state that you will eventually get to doesn't tell you anything about how long it will take to get there. And you have to actually ask about the specific

25:10conditions the universe is in and how the processes go. The universe came out of its early stages almost all hydrogen and helium, at least in terms of the ordinary matter. Forget about the dark matter. It doesn't really matter for this. Now you might seriously ask why the early universe didn't make more heavy elements all the way up to iron. And this is a fascinating story and you know any cosmology student learns about the story of Big Bang nucleosynthesis

25:41which is exactly this story. There's something that you learn about called nuclear statistical equilibrium which says okay not just the fact that iron is the lowest energy state but what about the state at some fixed temperature? What if you just had a box of gas with a completely indestructible material that the box is made out of and I can turn the temperature up to whatever I want? At very high temperatures iron is not the ground state because the iron keeps bumping into other things and dissociating

26:12and you know photons break it apart and so forth. At very very high energies protons and neutrons and electrons are the ground state of that high temperature gas and then as you lower the temperature you can make more and more of these heavy elements and they can become at least temporarily stable but the point is you need time you need time to turn all those light elements into heavier ones and the early universe doesn't give you time by the time the universe is three minutes old

26:42it's become sufficiently dilute that you don't get a lot of collisions between the protons and neutrons and helium atoms enough to make heavier elements than that you make a little bit right you make trace amounts of lithium and beryllium but you don't have nearly enough time the universe just cools off and dilutes away so fast that you don't have time to go all the way to iron if the universe expanded much much more slowly it would have been a different story

27:13Scott Ferris says as LLMs are progressing with their ability to do complex math do you utilize any AI in your personal research if so which ones have you found most useful are there strengths or weaknesses with the LLMs mathematical abilities that you found interesting or surprising I do use LLMs all the time but not to do anything complicated like real math if I want to make a little plot like I did in the recent paper that we had about the cyclic universe you know we had a very well

27:43posed set of equations I just want to plot the solution to the equations okay like it's much easier I could have written some routine in Python or Mathematica to do that it's much faster to ask the LLM to do it and they make very pretty plots out of it right and I can check it it's a short program and it's reliable because I'm not asking it to do anything that's outside it's wheelhouse right when you want an LLM to make a plot for you it's very very helpful to know that you're not trying to do something crazy you're trying to do

28:15something that has definitely sort of seen similar things to in the past but most of my research isn't solving tricky high-level math problems right most of my research is much more conceptual trying to figure out what are the equations that you should be solving in the first place and that's stuff that the LLMs are just not any good at at all and so I'm not someone who needs or uses LLMs in my science research that much I use them a lot more in my popular writing

28:46because I'm constantly bumping up against areas where I know something about it but I'm not the world's expert right so that's the perfect epistemic condition to be in to find LLMs useful where I know enough about an area to know the general lay of the land and to be able to tell when the LLM is lying to me but it is nevertheless super helpful in pointing out new papers or new ideas or drawing connections or things like that I don't I'm not

29:17a sufficiently frequent user to tell you like which LLMs are better at what tasks or anything like that sometimes I'll try it on both Claude and ChatGPT those are the ones that I tend to use as I've said before I would never ever use it to write anything I think that's complete that's self-undermining for all sorts of reasons as well as destroying trust between you and the reader but super helpful for me to like understand this theorem that I know but I want to make sure I know all the loopholes

29:48and things like that right to ask it questions about those kinds of things Gilbert Rodriguez says thoughtful people tend to hold their beliefs loosely since no proposition is in principle safe from potential new evidence but even tentative statements are themselves propositions fully subject to Socratic questioning so while I respect the humility of holding no belief sacred I struggle to justify holding any belief at all because all justification however intricate eventually bottoms out

30:18even my justification for the thing I just said so is a radical suspension of judgment the necessary end of epistemic humility should we all strive to become Peronian skeptics no no we should not and I think that the so for those of you who don't know the Peronists back in the day in the ancient days were skeptics were people who were you know not just skeptics of Bigfoot that wasn't something I had to worry about or UFO sightings but skeptics of any knowledge at all as a possibility

30:48and there's an argument for that like you know how do you know for sure but interestingly I think that the reason why the skeptics are wrong is the same reason why the people who think that they have absolutely certain beliefs are wrong I think that the common mistake of those two attitudes is to think that unless knowledge is 100% reliable then it's 100% unreliable right I think that's the trap that both sides fall into but once you believe that knowledge

31:19is provisional and you should be able to update it then there's no reason at all to be a skeptic you say like okay I have these beliefs with these credences and I'm going to see how well they do okay I talk about this in the big picture where I talk about the idea of planets of belief you have a set of beliefs that consist of all sorts of different beliefs that relate to each other in different ways and you're hoping to find something that is self-consistent and consistent with your

31:49external evidence and it might be that a piece of new data comes in that not only changes one of your beliefs but completely undermines your whole picture right and your planet of belief sort of blows up and you have to build a new one out of the rubbish or the detritus that comes out of that and that's very difficult to do this is why people tend to stay in their overall worldviews once they are adults it's very very difficult to get people to change their overall picture because every element

32:21of that picture is closely intertwined with a whole bunch of other elements that you're going to have a lot of difficulty overturning it just becomes really really difficult to do so I don't think there's anything wrong with having a set of beliefs all of which you have credences for that are not either zero or one that you've tried your best to make self-consistent and consistent with the evidence out there you'll never be 100% but that's completely fine that doesn't mean you should be zero percent Rue Phillips says I'm going on a

32:52Route 66 trip with my wife and teenage kids we're stopping in Santa Fe on our way to Albuquerque what suggestions do you have for us to do and eat are things like catching a lecture at the institute or visiting Los Alamos doable we will probably just be there half a day well I mean there's a million things to do in Santa Fe there's almost nothing to do in Albuquerque by the way I don't know I don't know why in the world you would stop in Santa Fe on your way to Albuquerque just stop in Santa Fe it's a smaller town

33:23but it's a much more interesting town and I say this I've spent a lot of time in Santa Fe but I've flown in and out of the Albuquerque airport a lot and I've certainly tried to look for something to do in Albuquerque without any success whatsoever there's an annual or maybe even more than annual balloon fair that I once air balloons right hot air balloons that is gorgeous I once flew through it or drove through it just by accident going home that was kind of a lot of fun if you happen to be there at that time

33:54that's good otherwise Santa Fe totally dominates Albuquerque in terms of things to do the food is amazing in Santa Fe there's a million restaurants so Santa Fe is a weird thing it's the capital of New Mexico it has this sort of scientific cultural side with the Santa Fe Institute the nearness to Los Alamos the Santa Fe opera is amazing and it also has this artistic side if there's one thing to do in Santa Fe if you're only going to be there for half a day

34:24if you have any interest at all in art go down to Canyon Road and just do a walk up and down the art galleries that'll fill half a day no problem whatsoever and you might even find art you want to buy right it's high level fine art but it's affordable it's not like $30,000 for a painting but it might be $1,000 or $3,000 or something like that if that's how you are inclined if not you can just like hang out you can do some shopping you can get some of the best cowboy boots

34:55you've ever had a lecture the institute itself SFI does not host lectures nor do they even encourage people to come visit right it's a relatively small sequestered campus they put on lectures but they're located usually at the Lenzic Theater so the Lenzic Theater is a wonderful theater in downtown Santa Fe which has all sorts of music and cultural events so they'll have lectures from SFI I've given them other people

35:25give them all the time usually like once every couple weeks but there's also musical groups that come through other sort of cultural things you should check out the schedule for the Lenzic Theater while you're there and you know have a good meal have either there's super good fine dining at places like Sazon or Geronimo but there's also just super good burritos and New Mexican food just don't call it Tex-Mex or Mexican food call it New Mexican or Southeastern cuisine that would be my tip get the get the Chile

35:56dishes one way or the other good Christopher Smith says do you have any thoughts on the de-extinction research of colossal biosciences and their pursuits to bring back to life the woolly mammoth saber-toothed tiger the dodo and other extinct animals I just listened to the audiobook of Jurassic Park this summer and I feel like the ghost of Ian Malcolm is warning me that this is not a good idea I don't know I have no strong feelings I guess I wouldn't even say mixed feelings I don't have very strong feelings

36:26about this it's kind of like a gimmick I don't think you're going to learn a lot scientifically I think I don't know a lot specifically about colossal biosciences so I don't mean to be opining on what they're doing in particular but I know a lot of these de-extinction efforts are absolutely cheating right I mean they're taking like a little hint of the DNA from some extinct animal and fusing it with the DNA of living animals and not really getting 100% of what the original animal would have been

36:56obviously if you're talking about something like a saber-toothed tiger or a woolly mammoth there's just huge questions here about what is the environment in which these animals are going to live you're going to keep them in a zoo you're going to like let them run around are they in any way adapted to the real habitats that might be available to them it just it seems a little silly to me like when all sorts of presently existing species are in danger of going extinct that you're going to spend a lot of time on bringing previous ones back

37:28for a gimmick of some sort I don't know there might be something out there scientifically to learn that I don't know about but I'm not quite sure what the justification is really okay I'm going to group two questions together Bob Ritchie says according to ChatGPT the number of people worldwide who use AI as a daily companion has grown from less than 1 million in 2022 to 30 to 60 million today what are your thoughts on this and Igor Volotic says what are your current thoughts on AI progress

37:59and its consequences how do you picture the world in 5 years how in 10 are you an optimist so I think you know I'm not especially convinced I have a great talent for predicting these things so I'm not going to give you any strong opinions about this I do think that AI is a transformative technology I've said that many times I've said like the lower limit of how important AI could be is how important cell phones are okay which is pretty important it's changed people's

38:29lives in some way the upper limit is much higher than that it could be much more transformative than that what gets me is there's I don't I don't know of any technology that I've ever been aware of happening in my lifetime where both the use cases and the misuse cases are so powerful and so many people have difficulty distinguishing between them so on the one hand

38:59you have people who just want to put AI in everything where it doesn't belong where it doesn't help people who have this complete weird conviction that AI can do everything better and then let it do things and then they realize oh my goodness it really wasn't any good and we have to go back right all these companies that fired people and replaced them with AI and realizing oh now everything sucks and we need to go back because we didn't realize the actual importance of the people that were actually doing this and then on the other hand

39:30you have people who think that AI is just inherently evil or at least LLMs are evil or at least modern companies that do it are evil that they would never touch it that it is somehow unclean and you know they're missing a lot right it's like saying that Wikipedia is somehow unclean I have this issue with writing like I've also like I've often said like I have a lot of writer friends some of whom are happy to use AI but others are like I could never use AI because my writing

40:01comes from me and I want to say like yeah sure your writing should come from you that's not a reason that's just a non sequitur that's not a reason not to use AI that's why does that mean you can't use Google you can't use Wikipedia you can't read anything you know there's ways to use it that are very helpful and very legitimate and ways to misuse it and I think that the weird interesting thing about AI is just how easy and tempting it is to misuse it

40:32right if you're trying to write an article on you know the recent diarrhea outbreaks from this pathogen that is finding its way to iceberg lettuce so you're googling a little bit about this pathogen or whatever that's fine but then you ask the AI to do it the difference is that what the AI gives you is something that looks very much like you could just cut and paste it into the article you're writing right Google doesn't typically do that or even if it did

41:02if you find a webpage that has a paragraph that someone wrote that is exactly what you wanted to say no writer is really tempted to just cut and paste it and call it their own but if ChatGPT gives you exactly the same paragraph there's some part of your brain that thinks eh I made that right I asked ChatGPT to do it therefore it's mine and I can just cut and paste it and call it my own which is entirely wrong in my view you know

41:33in my book The Physics of Democracy I'm using I'm what is I guess using it gives the wrong impression I am asking for help from LLMs as I just said very often but never in a million years would I cut and paste from the output into the writing I think students and I'm getting a little bit away from the questions here I know because I'm just sort of embroiled in the particular versions

42:03or aspects of this which are most relevant to my life students are these days it's just hard to resist using AI to do their assignments okay that's just true many of you have seen this thing from a professor from Brown I think it was either economics or history I forget which one he was but he was giving all these he was giving exams and he was giving them all take-home exams and suddenly

42:34in the last year or two unlike previous years everyone is getting 95% on the exams they used to get an average of like 70% and so he switched in the middle of the course he said okay the next exam is going to be in class and what happens is several people dropped the class those who didn't like two or three of the 50 students in the class got the same grade on the in-class exam as the take-home exam everyone else did much worse

43:04and this is a disaster because I mean it's absolutely partly the students' fault a large part the students' fault but also a large part the system's fault academia's fault because we have been telling them for years that your goal is to get good grades and we've been telling them that because we think the royal we that as long as they work hard to get good grades like it or not they're going to learn something okay and that connection has been broken by AI

43:35now with AI you can get a good grade if it's take-home work-at-home assignments without learning anything at all so we have to dramatically change how we do it and part of that is you know like I don't do take-home exams anymore for exactly that reason but also I think we need to explain to students that the work of thinking things through and writing your own stuff and your own

44:06whether it's a problem set solution or an essay or whatever is part of learning learning is not just producing the result and you know there's jokes out there but the jokes are cutting close to the bone of you know people showing up to a job interview and being asked questions and they're terrible at giving answers to the questions because throughout the last few years all they've ever been doing is asking AI for the answers to the questions so you know job interviews and student evaluations and academic papers

44:36are a tiny fraction of what AI is relevant for I think AI is an incredible we say AI it's really LLMs okay I know that there's careful people who are listening to this who understand the difference LLM is a particular approach to AI but it's not AI it's not they're not equivalent these particular technologies are going to be super useful they're also super misusable and that's a weird thing I don't know if we've ever had that kind of situation before

45:07so I don't know whether I'm an optimist or a pessimist about that you know we had this recent incident where OpenAI was doing a test and it was you know challenging its AI to do this thing and the AI found out how to like jailbreak it got out of its containment it sort of found the answers to the test by hacking into some other computer somewhere else and people like ah see I told you AI is very dangerous and bad but

45:38if you look up what actually happened you know there was there were safeguards put in place to prevent that from happening and OpenAI turned them off because they wanted to be a little bit more efficient and they thought it was not a big deal and this is exactly what I've been saying for a long time the real AI is yes very very very dangerous but it's only dangerous because of good old natural human stupidity it's not dangerous because the AI is going to become super intelligent and talk its way

46:09out of its box it's because we're not that smart and we're going to open the box and we're going to let it do things that are potentially disastrous for us that's going to happen there will be AI disasters just because human beings not that capable of handling these things insurance isn't one size fits all that's why drivers have enjoyed Progressive's name your price tool for years now with the name your price tool you tell them what you want to pay and they'll show you options that fit your budget so whether you're picking out your first policy or just looking for something

46:40that works better for you and your family they make it easy to see your options visit progressive.com find a rate that works for you with the name your price tool Progressive Casualty Insurance Company and affiliates price and coverage match limited by state law pop quiz what's in your kids lunchbox at Whole Foods Market they've already done the studying over 300 food ingredients are banned from their shelves no hydronated fats in the peanut butter and no high fructose corn syrup in the cookies and for sandwiches

47:10there are no synthetic nitrates or nitrites in any of their deli meat so you can pack lunchboxes with peace of mind get back to school ready at Whole Foods Market alright Robert Kitsie says nice score finally getting Bonnie Bassler on the show what an endlessly suggestive area while my mind is still reeling from the thought of where my five pounds of personal bacteria are swimming and what they're talking about two specific questions took up residence in my head during her episode so I will note

47:40for Robert and for everyone else as many of you know you're not allowed to ask two specific questions you get to ask one question in each AMA and so ask the one you want answered so I'm answering Robert's question because the first of his questions has to do with bacteria and cancer and my answer is I have no idea so I'm not even going to bother thinking about that one the second question is I have almost no idea about the second question but it's bacteria as epigenetic information vehicles are there any

48:11serious ideas or evidence that bacteria might play a role as an underlying vehicle for cross-generational epigenic information transfer for example could stable microbiome patterns across generation modulate gene expression in ways that mimic or complement germline epigenetic inheritance so I'm not exactly sure of all the details here right you're asking a physicist slash philosopher about molecular biology but it is absolutely true that there

48:42is inheritance epigenetic inheritance from the microbiome we're learning about this this is something that is a cutting edge thing one way it shows up is there's a difference between being born by ordinary birth birth canal birth versus cesarean section in a cesarean section you know you cut through the belly into the uterus and remove the baby

49:12it's actually quite common that is a pretty darn common thing especially here in the united states and it makes certain things easier certain things harder but one of the things is people have realized that the journey through the birth canal that the baby takes is a place where it inherits some of the microbiome information from the mother and by doing a c-section you're not letting that happen and so c-section babies are often sort of not getting the benefit

49:42that they would traditionally get from inheriting that information it's not deadly but it can be a thing that you need to take care of or at least to take into consideration now I don't know the details between the distinctions between like the microbiome and bacteria in particular are there things that are in the microbiome that are not bacteria I don't really know but it's absolutely a great example of the whole connectedness

50:13of biology and how it is a complex system and how every little thing matters you do one thing slightly differently and there's a whole bunch of unintended consequences that come along that you might not have noticed this is what we're trying to understand better and better and people like Bonnie are helping us do that Steve Bonner says neutrino researchers say that it's not possible to know both mass and the flavors of neutrino very precisely which I assume is due to Heisenberg uncertainty but that's usually stated using position and momentum does the neutrino version

50:44follow from that more familiar definition it basically does like morally it does it's the same kind of thing and you're right that what we call the uncertainty principle is not just position and momentum that is indeed the way that it is usually stated because those are two things that people are very familiar with positions and momentum from classical physics there is a version of the Heisenberg uncertainty principle that works for the spin of a single particle you know you might have been told

51:15that if you measure the spin of a single particle like an electron if it's a spin one half particle you're only going to get two possible answers spin up or spin down you may also have been told that you can measure it again along different directions right you have the z direction which just for historical reasons if you have axes xyz the direction in which we usually measure a spin by default is called the z direction okay but you could also measure it along the x direction and if you have a wave function that tells you the probability

51:46of getting a spin up or spin down in the z direction there's a simple formula that converts that into a probability of getting spin right or spin left along the x direction okay and there's an uncertainty principle if you are 100% spin up in the z direction then you're 50-50 spin left or spin right in the x direction and vice versa if you're spin right 100% then you're 50-50 spin up versus spin down so the uncertainty principle is just a way of saying there is no quantum

52:17state in this context there's no quantum state that is simultaneously definite in the z spin and the x spin of a particle it's exactly the same formally mathematically as saying there's no quantum state that is 100% definite in both position and momentum for a particle and it's basically the same there's a few quantum field theory important aspects going on that we're glossing over here but it's basically the same for the

52:48mass and flavor of a neutrino knowing what the mass is so let me let me back up and say that the most important single thing that I should have said right from the start it's not about knowing it's not about our knowledge okay and this and this is the way the question is phrased you say it's not possible to know both the mass and flavor neutrino very precisely if there's one thing that I can help people understand about the uncertainty principle don't call it a statement about what you can know it's a

53:18statement about what can exist if you know the spin is up along the z direction it's not that you don't know the spin along the x direction it's that there is no definite answer there's no fact of the matter about what the spin is in the x direction I know this bothered Einstein a lot and this is where the whole if you dig into the EPR paper this is really what he's complaining about but that's what quantum mechanics says likewise it's not that you don't know the position or the momentum it's that there is a quantum state and there

53:49are no quantum states where both position and momenta are definite likewise there's no quantum state where both the mass of the neutrino is definite that is to say it's in a mass eigenstate and the flavor of the neutrino is definite that's to say it is in a flavor eigenstate so there are states where the mass is definite there are states where the flavor is definite they're just not the same states any one is a combination of the others just like the spin up is a combination of spin left and spin right

54:21okay Erkan Sertali says did you ever visit or plan to visit Turkey as a cat lover yourself I think you'd be delighted to meet the world famous street cat population there specifically if you come to Istanbul I urge you to visit Katakoy we have the fluffiest and friendliest kitties there they love getting pets and food in some parks they jump in your lap the moment you sit on a bench I've not ever been to Turkey it is one of the places if I have like a short list of five places that I do want to visit at some point

54:51Turkey is definitely one of them for the history for the culture and for the kitties yes I'm like I'm not gonna pretend otherwise you you make a good case you're talking my language I would like very much to get you know some good Turkish food take it to the park sit on a bench bring a good book have a cat jump on my lap as I eat my lunch and and read my book so someday I will do that I don't have any media plans but that sounds like a wonderful way to spend some time Michael Lacey says

55:22I'm starting to research places where I might retire and Chicago is on my list you mentioned that you enjoy the restaurants and theaters in Chicago is there anything else you can tell me about living there any good neighborhoods I should check out I'd like to ditch my car and live in a walkable area with easy access to public transit I would say that Chicago is pretty doable without a car there's certainly areas that are super walkable right like you can absolutely live and go to restaurants and

55:52places like that walking in Chicago that's not a problem nevertheless I'll just mention just in case cars are pretty easy in Chicago it Chicago does not have the horrendous traffic that Los Angeles has nor does it have the weird narrow streets that the place like Boston has I live in Chicago for seven years I drove all the time now the reason I drove is mostly because some of the best neighborhoods to live in are on the

56:23north side and the University of Chicago is on the south side so you have to get there and for weird historical reasons you know so roughly speaking the south side is the poorer side of Chicago and Chicago was one of the most actively racially segregated cities in the United States for all sorts of reasons so the university is on the south side and the university didn't want or I shouldn't say the university the university is in a

56:53neighborhood called Hyde Park named after the similarly named neighborhood in London and Hyde Park is quite nice but it was historically surrounded by not so nice neighborhoods now of course cities in the United States are generally improving in conditions so the sort of nice neighborhoodness is growing around Hyde Park and the new Obama presidential library I think is nearby and other things are good things are happening so things might even be changing since I was

57:24there but anyway the point I'm trying to get at is that historically the people of Hyde Park did not want public transportation to go there they did not want it to be easy to get in and out of Hyde Park so there was no easy way to get from the north side where I wanted to live to the south side where I worked so I just drove a car up and down Lake Shore Drive and it was actually quite pleasant because you're driving the lake is right there I mean I would probably if I were planning the city not put a freeway right by the lake because they should enjoy the lake for other reasons but it

57:55was there and it's enjoyable for the people driving but if you don't want to yeah just live on the north side it's very easy the exact center of the town is called the loop because the subway does a loop around there the it's not a subway it's an elevated train and it's pretty good I would say I mean the it's a commuter kind of public commuter centered public transportation network so it's it's mostly to get people from outside downtown into the financial

58:25district in the loop downtown and it's not as good for getting from interesting part of the city to interesting part of the city okay but I think you could totally live there without a car by picking a walkable neighborhood taking public transportation down to the loop and Michigan Avenue which is the big shopping district etc and then just taking an uber or whatever when you want to go further afield that's pretty straightforward the weather in Chicago is just not good there's just no other way of saying it it's humid and miserable during the

58:57summer it is cold and very snowy during the winter as soon as it gets nice in the spring there's like this burst of people going outside going to the lakefront and everything and enjoying it but everything else besides the weather is great the culture is great the best in my mind theater scene in the United States because it's exactly the sweet spot where the theater is really really professional and creative and vibrant and yet the people who are there are

59:29not trying to make into Hollywood or TV or movies or whatever right they're actually there to do the theater so Steppenwolf and the Goodman and many many little tiny theaters have incredibly good people the music scene is incredible the restaurant scene is among the best in the United States so museums and and all those things so I think it's a great choice just understand the weather it's a thing there everything else about Chicago is good Sean Bentley says your last

1:00:00episode with Bonnie Bassler was fascinating it got me thinking of some analogs bacteria are single-celled organisms that can work cooperatively via quorum sensing they evolve into eukaryotes which are multicellular while their individual cells don't form an organism but their cells essential their cells essentially work together to make one it makes me wonder if we were bacteria is something like the Borg from Star Trek and analog for eukaryotes could we be evolving to form us to evolving to a form of shared consciousness I don't see evidence of a

1:00:32biological mechanism but who knows that the internet and AI could look like 500 years from now obviously not something really answerable but I thought it was fun to think about yeah so just to be super clear eukaryotes we currently think actually came about from a symbiosis between bacteria and archaea which is the other big set of single celled organisms out there they joined up and it's all a little mysterious and the mitochondria that we know now so like I always thought that you know the

1:01:04whole point of eukaryotes is that their cells with nuclei like bacteria and archaea don't have nuclei in them eukaryotes do and I knew that archaea and bacteria joined together to make eukaryotes and so I thought that the nucleus was the thing that was joined but it's not the nucleus sort of formed separately it's the mitochondria that are the remnants of the bacteria that joined with the archaea to make eukaryotes so again very complicated all these sort of

1:01:34interconnections does any of this have to do with shared consciousness you know I think that shared consciousness is harder than it looks just because of physics constraints you know you're not really sharing a consciousness unless you can communicate very very quickly back and forth between the different parts of you one of the reasons why the brain works as well as it does invertebrates et cetera is because you can pack those neurons pretty carefully pretty closely to

1:02:06each other as the set of neurons grows bigger and bigger it takes more and more time for signals to go from one end to the other which doesn't seem that bad even as big as an elephant or a whale it's still doing pretty well but at some point it's going to give out right at some point it's going to take more time for signals to be processed in your brain than is biologically favorable to surviving right you need to make decisions in a world that is harsh and things like that will technology change that

1:02:40in any way I don't think so but I do think that the idea of neural networks neural networks is the wrong word right mind reading neural invasions of your brain and reading the signals and sharing them with other people is it's not a near-term technology that's going to be very practical but I do think it's a technology that is absolutely feasible down the road and that might very well change things in some dramatic way that

1:03:11I can't really think about but you're right it's fun to think about anonymous says I'm a junior faculty in threat theoretical computer science so designing algorithms for NP hard problems I am quite alarmed by the recent progress of LLM slash AI systems in our area and discrete math in the last few months for example recently the famous Erdos unit distance problem was solved by an open AI model it appears that entry level questions that you would normally

1:03:41give to undergraduates or early graduate level students can be easily solved by LLMs and looking at the rate of progress even run-of-the-mill problems that sustain the career of mediocre researchers like me can be solved soon so I have a few related questions is this happening in other theoretical fields e.g. theoretical physics how do I deal with the existential dread that my career may not exist in a couple years at this rate what would your advice prediction regarding adapting research philosophy in such theoretical fields so again you're not allowed to ask three questions but I'll sort of answer one kind

1:04:13of big overarching question I think that there's a mixture here I think that on the one hand the things the world's going to change some things that were perfectly respectable parts of the scientific enterprise are going to go from being done by humans to being done by computers I think that's more or less inevitable and if you feel bad about that it's too bad really nothing we can do about it you know like it used to be that multiplying numbers

1:04:43together was something human beings had to do and then pocket calculators took that over same thing for all sorts of things it used to be that you would walk or take a horse and buggy and now you drive a car things change right I don't think that that I think that our imaginations are not good at seeing what exactly the changes will be there will be changes so yeah you know disproving some conjectures or doing some calculations things that used to be perfectly good problems for human beings

1:05:13are just gonna the computer is gonna be much better at them than we are I don't think that that's anything we can do anything about nor should we try I also don't think that that's actually going to remove the need for human beings there's sort of other things that human beings can do I mean let's imagine the limiting case I don't know I don't think this is going to be true but maybe it will be imagine that there are just no problems in math that human beings are better at than computers okay again I don't think that's going to be true but let's imagine that it would be true on the one hand

1:05:46there would be a certain kind of romantic sadness that the era of human beings taking up these great challenges and doing their best to batter that their brains against these mathematical problems is now essentially over right still there's more to life than that right you know there's still the task of human beings understanding these problems like one thing that the

1:06:17LLMs are very bad at right now and might always be bad is coming up with new problems you know they can come up with small changes on the old problems but the really profound questions that you know we get around to LLMs are not that good at and again even in the limiting case where LLMs are just always better than us there's still the task of human beings to understand what the LLMs have taught us right there's a difference between just being told the answer to a conjecture and really understanding it if if you're if

1:06:47one was truly in it just for the joy of understanding I don't think that's affected very much by the progress of computation whatsoever just because you know you can ask an LLM a question and give you the answer you don't know the answer you don't appreciate how it got there now not to mention the fact that it might be wrong but we're putting aside we're imagining a hypothetical future where it only gives correct answers there's still work for you to do in your brain to work

1:07:18to understand that you know the fact that computers are better than human beings at playing chess or playing go hasn't stopped people from playing chess or playing go it might be that doing math math becomes like playing chess something that you know a computer might be better at than you but you still do it because you think it's fun I think that in the you know like it often happens that when technology means that human the old fashioned way of human labor doing

1:07:49something has been replaced or improved by technology what happens is not that the human element goes away but it finds something different to do right you know you know my favorite my favorite analogy for AI is wrist watches because it used to be that human beings made these mechanical devices that were incredibly ingenious and and every if you had a wrist watch you had

1:08:21an incredibly ingenious mechanical device on your wrist and then we invented quartz timekeeping and that was much better I mean a quartz watch is both more accurate and cheaper than a mechanical watch and so this was called the quartz crisis in the watchmaking industry and a lot of watchmakers either shut down or just started making quartz watches but then they rediscovered that there was kind of a romantic art in a mechanical wristwatch and they rebranded as a luxury good you know and now and so

1:08:52multiply the price by 10 and you can still sell watches to suckers like myself who think that this is actually quite romantic so I think that what will happen is it will change it will change in a dramatic way math is really the sort of prime target for this kind of thing physics and other sciences are less on the firing line but they will eventually get there I'm not I'm not fooled by that but exactly because math is about proving theorems this is much

1:09:23more in the wheelhouse of what computers are good at than physics or chemistry or biology so math is the test case I think that the human part of doing math might dramatically evolve but I don't think it's going to go away you're listening to this podcast so I know you've got a curious mind here's a helpful fact you might not know yet drivers who switch and save with progressive save over nine hundred dollars pop over to progressive.com answer some questions and you'll get a quick quote with discounts that are easy to come by

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1:11:29probability appearing in the density matrix obtained by tracing out part of the universe is not fundamental therefore I don't see how classical probability distribution over the space of possible universes is supposed to make sense I'd be curious to hear how you reconcile that so I think that the mistake is right where you say entropy is usually formulated in classical probability the thing about entropy and I've said it many times is there's many different notions of entropy you can't say here's what entropy is I'm not gonna listen to anybody else's thing okay whenever you're dealing with entropy in a particular consideration in a

1:12:02particular context you have to say okay which version of entropy is the one appropriate to the question I am asking in the context of the arrow of time and the past hypothesis and the early universe the appropriate notion of entropy is the Boltzmann entropy the entropy that is written on Boltzmann's tombstone s equals k log w none of those symbols s equals k log w have anything to do with probability they just

1:12:33don't it has to do with coarse graining and macrostates w is the volume of a macrostate a macrostate is the set of all microscopic states of the theory with the property that they look the same according to some macroscopic observables and of course there's some judgment and people argue and it's full employment for physicists and philosophers to say well what do you mean by a macrostate what are the observables etc etc but who cares none of it has to do with probability whatsoever it has to do with what can you observe about

1:13:05the system and how many microstates of the system are compatible with those observational outcomes the important fact about the early universe is that given what we know about it given the macroscopically observable features of it whether that's at the surface of less scattering or wherever you can count the number of microstates that would look like that and it's very very small right that's the low entropy of the early universe that has nothing to do with probability it's just a feature of physics of cosmology of

1:13:39what was going on back then so whenever these entropy puzzles come up the first thing you should ask yourself is am i using the right definition of entropy maybe that's the problem dominic german says regarding last month's discussion on diversity and dei your position seemed to be that hiring based on skin color is an effective albeit imperfect method for increasing diversity in the workplace and therefore dei is a net positive is this a fair characterization of your view if not could you clarify i

1:14:09appreciated your response and agreed with a lot of it but dei still feels like discrimination based on skin color shouldn't we want skin color to be as trivial a detail as hair color or eye color so for the first question this is fair characterization not exactly fair you know you're getting at something i do think that increasing diversity is a net positive and therefore policies that increase diversity are good overall that's not the only reason why i'm in favor of something like affirmative action or in general taking skin color into consideration

1:14:41i do think that there are elements of fairness and equitability that we should indeed to go to your last question should we want skin color to be as trivial detail as hair color eye color we should want that but we live in a world where that's not true that's not even anywhere close to true and recognizing that we don't live in such a world is part of why we need to nudge the scales a little bit to make it closer to that world you know i once wrote a blog post about this called

1:15:12spontaneous social symmetry breaking and it was an attempt to put forward an allegory a metaphor for this situation i noted that look in the standard model of particle physics if you just look at the bare equations that tell you how things go what we call the electron neutrino and what we call the electron are basically the same they are symmetric they obey a symmetry relation that relates them to each other there's no difference between those two things but it would be absurd to

1:15:42therefore say well we should treat the electron and the neutrino as the same because they're basically the same the reason why is because we live in a world where that symmetry is broken there's a higgs boson in the background and so in the real world electrons have electric charge neutrinos do not etc the idea being that you might want a world you might think that the underlying moral universe treats people exactly symmetrically with respect to their skin color but the actual world we live in doesn't and therefore it's absurd

1:16:15to pretend that it does especially if that pretending only happens for cases where after being living in a world where skin color matters and matters and matters and matters disadvantaging one group suddenly people worry when it matters the other way disadvantaging some other group that's obviously incoherent we live in a world where government agents are hunting people down on the streets based on their skin

1:16:45color we live in a world where the supreme court of the united states has declared it constitutional to disenfranchise and disrepresent populations of people because of their skin color and various states in the south have raced to do exactly that we live in a world where the department of defense fires senior generals because of their skin color we live in a world where the world's richest man uses a media platform to advance white naturalism naturalism because of people's skin color we live

1:17:17in a world where there is ongoing discrimination in real estate the job market and elsewhere because of people's skin color we live in a world where the only refugees being currently allowed into the united states are white people their skin color truly matters we live in a world where there's been an unhinged reaction to the idea that actors in a movie based on greek mythology have the wrong skin color so if if somehow like all of this you can sort of live with you're like yeah you know

1:17:49that's okay but then suddenly you get outraged when we try to hire people or let students into universities at a rate which is approximately reflective of the rates at which different people live in our society then you need an update on your sense of fairness here i think i would love to live in a world where skin color is as trivial a detail as hair color or eye color but i have my eyes open and i live in the world we actually live in and i try to deal

1:18:19with that the best i can sam hartzog says the coincidence problem didn't strike me as a problem when you raised it in your dark energy episode my intuition said of course the most interesting dynamics in the system would appear around points of transition or inflection i understand why it is problematic after listening further but i wonder is there anything to that intuition about transition points does it make sense to a priori assume that we would have appeared near the transition between too crowded where cosmic events were wiping out fledgling life forms and not crowded enough where

1:18:52sparsity makes a confluence of life-sustaining conditions less likely to arise you know i think that there's some correct intuition going on here um you know as you will read in the upcoming emergence and complexity book um there are critical points of behaviors in certain physical systems where you get interesting behaviors on all scales and that is absolutely the kind of thing that feeds into the birth of complexity and life and so forth but you can't let these sort of general hand wavy principles guide everything when you think about

1:19:25what matters you know the coincidence problem is a is completely on board with the fact that you know interesting dynamics happens at points when it can happen in this case the formation of planets and stars and life but separately there's something called the cosmological constant okay the cosmological constant in its natural way of being would have been so big that those moments would have just lasted seconds or fractions of a second and therefore there

1:19:56wouldn't have been enough time for all this complex stuff to happen the anthropic answer to the coincidence problem is getting at what you're pointing at it is saying that the vacuum energy needs to be small enough to allow for there to be time for all this interesting dynamics to occur but if you don't believe in the anthropic answer to the cosmological constant if you think there is some formula that at the end of the day will tell you once and for all what the vacuum energy is the fact that that formula gives you a value that allows for

1:20:28all this interesting dynamics to happen is highly highly non-trivial and we don't know why that would be the case Ruka says as your podcast is the main reason why I give many worlds a chance here's the question that my mind keeps circling on are the worlds of many worlds really unavoidable I do have the feeling that many worlds is on to something it's just that I can't figure out if it's my bias that keeps pushing back or if that's a hint of a flaw of the theory well they're not unavoidable no you can change the theory to get rid of them right they pop out of

1:21:00quantum mechanics quantum mechanics which was a theory developed in order to fit the data back in the early years of the 1900s came up with this idea that what you observe is not fundamental that the way we describe the world when you're not observing it is as a superposition of different possibilities and therefore it allows for the superposition of different worlds and then you just ask do those worlds come into existence under the ordinary evolution of the universe and the Schrodinger equation says oh yes they absolutely do that's not unavoidable in

1:21:33any way you just have to change the theory it's unavoidable if that's your theory if your theory is the quantum state represents reality it obeys the Schrodinger equation all the time and there's nothing else going on then the worlds are unavoidable Thomas Anderson says I've recently become interested in the use of contact force concepts in relation to social systems for example the relationship between educational goals and measuring outcomes is sometimes described as being intention changes in policy can cause friction at implementation or said to have

1:22:04impacts yet to me as a sociologist the contact in question seems like it is different from a system like two cars crashing into one another quite a few social theorists have made use of these concepts but I'm interested in the view of a physicist on it of a physicist on it do social systems say anything interesting to you about the form that contact forces can take in physical systems you know my attitude towards all of this stuff is physics is special physics is special because it takes the attitude that you can simplify systems down to their absolute

1:22:40bare bones their spherical cow descriptions and you can analyze them in fiercely quantitative detail and maybe you can learn something and that that learning can be surprising right you can be surprised at what your own theory predicts like Einstein never would have believed in black holes never did know about black holes I should say he might have believed in them eventually the the equations are smarter than you are so therefore physics is special therefore it can be used to give you insight into other kinds of questions that are not necessarily physics

1:23:13questions because the study of physics forces you to go outside of your intuition like it forces you to go outside of what you would have guessed because the equations are saying this amazing thing is happening and you can listen very closely to that so therefore because physics comes up with these new questions these new concepts because you're forced to you can be inspired by those new concepts to think about other questions in new ways whether it's tension or friction or whatever these might be useful concepts for thinking about

1:23:46sociology or other kinds of social sciences or they might not be so I'm not saying that they need to be I'm not saying that the map between their use in the social sciences and physics is necessarily exact or one-to-one and completely reliable but use it to inspire you use it to start thinking about the problem in certain ways that's what I would advocate doing I would never take it overly seriously like if the data that you have in your social science investigation don't fit with a prediction that you made based on some

1:24:18physics-based model then believe the data okay don't believe the model Kyle Stevens says a recent paper by Anthropic not the principal but the AI lab suggests that LLMs may develop some form of access consciousness which emerges due to what they term the J-space the J-space is just a small collection of internal neural patterns that compared to all the models other internal processing play a special role and operate silently in the model's internal neural activations

1:24:48allowing the model to think about a concept without writing it down you have spoken at length about your beliefs that LLMs are not conscious though you seem in general to be referring to phenomenal consciousness do you think that LLMs may have developed some form of access consciousness no I do not I think that's pretty clear I mean this is the the research being described is perfectly good if people Anthropic and elsewhere have found that there's a way of talking about what is happening in the LLM when it's responding to a question trying to come up

1:25:21with an answer which you can sort of characterize as well one one aspect of it I'm not gonna I don't I haven't read the paper in detail I only know a little bit about it one aspect is you can sort of project onto a vector that describes the emotional state of the system is it angry is it calm is it happy these days and that gives you interesting non-trivial information about what form the answer is going to take it's not just you're doing this for fun it's actually predictive of what's going to happen there is a true fact about the statement related to the

1:25:54statement oh my LLM is agitated right now okay the words are doing all the lifting here I mean I hate to use this analogy because I think it's usually bad but this is close to the analogy of the guy writing on a piece of paper I'm alive and then putting that into the Xerox machine and the Xerox machine spits out a piece of paper saying I'm alive and the guy's like oh my god my machine is alive you know I think that you need to do much more work to claim that this kind of behavior is

1:26:27anything like what you and I think of as consciousness whether it be access or phenomenal consciousness maybe that work is doable but again given how LLMs work given everything that they're trained to do given how we design them given how they behave nothing in that makes me think that they're conscious or or should be conscious so I do think and I've said before I'll say again I do think that we as a society as academics doing philosophy and neuroscience and other kinds of things have done a bad job of stating ahead of time what we mean by

1:27:02consciousness so that if a computer actually achieved it we would be able to explicitly say that that happened but so be it you know I think that that would be a very important project to do but I don't think that LLMs are pushing us in that direction quite yet John Plasterer says I've listened to many of your podcasts including solo episodes and AMAs but I can't recall hearing about your views on Zurek's quantum Darwinism it seems that his work is compatible or even builds on an ever ready in many worlds some recent work provides some

1:27:33potential ways of explaining how the Bourne rule can fall out of the records that form during deoherence I'm interested in your thoughts on quantum Darwinism and if you feel that this may be a promising avenue to advance our understanding of the fundamentals of quantum mechanics so for those of you who aren't familiar which is probably most of you Wojciech Zurek who is one of our big names in quantum mechanics and the foundations of quantum mechanics decoherence and how decoherence works in particular I'd all be all in favor of Zurek winning the Nobel Prize for his work on decoherence I think it's that important his

1:28:05recent work not like within the last few months the last few the decade or so has been under the label of quantum Darwinism and it's all about how decoherence works right he was a pioneer in saying that decoherence works and these days he's working on the details which makes perfect sense like okay so how exactly does it work in particular there's this fact that you know when you and I are both in the lab when Schrodinger's cat is revealed when you open the box and there's a cat that is either awake or asleep we talk to each other and we see

1:28:37the same thing right it's not like I had a 50-50 chance of seeing awake or asleep and you have a separate 50-50 chance right and one way of explaining that or accounting for that is that the information about which branch you're on about what decoherence happened exists redundantly in the environment you know the reason why the cat is either awake or asleep on one branch or the other is because it becomes entangled with its environment and it becomes entangled very richly with the environment becomes entangled separately with in

1:29:08particular the photons that are heading out from the cat to your eyeballs and so you can go through some math and you can show oh yes we're gonna see the same cat so all this is a hundred percent compatible with many worlds for whatever reason and I've talked to him about this Zurek himself is a little bit reluctant to get on the many worlds bandwagon he's not necessarily against it but he doesn't think you need to go that far I just think that that's a failure of

1:29:38courage you have to be willing to accept what your equations are telling you so I think that the tools that he's built up the the technologies is extraordinarily useful for many worlds but I don't think that by itself if you're not quite willing to say okay here is my foundational theory of quantum mechanics that you're really going to answer these questions like the measurement problem the reality problem etc I think that he's trying to have his cake and eat it too and I think that that's a very venerable tradition in quantum mechanics of trying

1:30:14to have your cake and eat it too but I think at the end of the day you're going to have to bite some bullets and either have the cake and or sorry or eat it not and you can't do both Robin loose says in your recent mindscape episodes on vacuum energy and dark energy you noted that a pure cosmological constant remains the simplest and most robust explanation for the accelerated expansion while dynamical dark energy faces significant naturalness problems do you think mechanisms that could produce mild spatial or environmental dependence in the effective vacuum energy for example slight differences between over dense and

1:30:48under dense regions are still theoretically interesting to explore or do similar concerns make that direction unpromising as well well I'm not quite sure what that direction is and this is a good question to address because it gets to how physics works you know when you do physics you have the fundamental construction of your theoretical model which has I don't know some Lagrangian some fields or whatever you know some equations one way or the other and then you have the phenomenology of the model so given that underlying superstructure

1:31:22I guess you can't have underlying superstructure the underlying structure here are what you would notice you know there's changes from here to here this is the scattering and blah blah blah the point is you can't start at the end you can't just start with the phenomenology and ask about it without the theory the structure underlying it I mean you're welcome to start with the phenomenology and say okay what kind of theory would get me this that that happens all the time but you can't just work in the world of the phenomenology without the world of the theory

1:31:54so when you say mechanisms that could produce mild spatial or environmental dependence in the effective vacuum energy what does that mean how does that work how does that happen like if it's a scalar field I understand how it happens and what to say about it and that is exactly what people have been investigating if it's something else then whether or not it's viable empirically fitting the data is going to depend a lot on those underlying equations the particular theoretical model I mean of course it's worth exploring because dark energy is something we don't completely understand

1:32:27we had some expectations about it that didn't pan out we have observations about it that are very well fit by a cosmological constant but not perfectly well fit so it makes all the sense in the world to keep an open mind meanwhile my betting money is still going to go on the cosmological constant being right Marie Raskew says what are your thoughts on the reversibility of quantum systems through the lens of the many worlds interpretation I read that David Deutsch proposed reversing Schrodinger's cat by using quantum interference to show the cat's superposition splits into parallel universes rather than collapsing into

1:33:02a single reality I kind of really wrap my head around it can you help me I think that this is a tricky one because many worlds is based on the Schrodinger equation being precisely right or some upgraded version thereof and the Schrodinger equation is 100% reversible reversibility is built into the technology of many worlds it's right there but there's in principle reversibility and then there's in practice reversibility and the same thing is exactly true in classical statistical mechanics right like in

1:33:36principle if I mix cream into coffee and it gets all mixed up I could very very precisely move my spoon so as to unmix them in principle but in practice that's never going to happen and no experiment you're ever going to do is going to make it happen so a good way of thinking about when the wave function of a system branches into two separate worlds is precisely when the decoherence has become irreversible in practice in principle it never is but in practice that happens people try to get

1:34:10understanding and make money off of the idea that I'm just gonna have a little bit of decoherence and then I'm going to undo it like the whole delayed choice quantum eraser experiment is based on that and you can do that you can entangle something with a single qubit rather than a billion qubits in the environment and then maybe you can reverse it but then it really wasn't decoherence at all that I would I would argue so I don't think that there's any special traction to be gained by imagining doing

1:34:42these experiments because I would argue that precisely the regime in which you can reverse and undo the entanglement is precisely the regime in which you didn't truly have two separate worlds to begin with Ivo Majors says mathematics in the last few years has moved towards formal verification using proof assistance software such as lean l-e-a-n one of the benefits of this approach is presented as making mathematics more accessible instead of relying on the authority of experts one can check the proofs on their own what do you make of this trend could a similar approach be useful in other fields such as

1:35:16physics chemistry and even social sciences yeah so for those of you who don't know this is kind of a really cool thing that has been happening in math I'm not an expert on it Emily Real who we had on the podcast a while back is an expert and I've learned a little bit about it from her she's at Johns Hopkins also the whole wonderful thing about the proof of a mathematical theorem is that it's supposed to be objectively true right it's not just a matter of judgment it's yes or no it's a formal system you manipulate it manipulate the symbols using various rules and so it is tailor-made for being checkable

1:35:52on a computer and so finally people have made enough progress in actually doing that that it's become practically useful and lean l-e-a-n is one of the big software packages that people use for this I think it's great I think it's wonderful because you know it there are these stories of theorems that were claimed to be proven and people even published proofs of them but certain steps in the proofs were not understood by anyone except the author and so even and the author dies like eventually and so even

1:36:23though these theories are in the books is proven no one knows how to prove them okay and that's bad I think that's not how math should be so I'm very happy that we can upgrade to doing it in a accessible and checkable way is it going to be useful in physics chemistry and social sciences no mostly no because mostly in those sciences we don't prove theorems we're not starting from an agreed upon set of axioms and seeing what their logical consequences are we're proposing models proposing ideas based on

1:36:55how well they fit the data and knowing that our credence in them is never going to be exactly one or exactly zero it's just a very different thing than is being done in mathematics which is precisely why even though you didn't ask about this it's precisely why I earlier said that math is exactly the area in which computers in general and llms are an aspect of that have the biggest prospect for making dramatic changes in how things are done in that field julian voidel says do you imagine sisyphus

1:37:28happy so this question is referring to the story by albert camu myth of sisyphus and I actually reference it in the big picture um camu tells the story of sisyphus sisyphus is cursed by zeus to push a rock up a hill all day and then at the end of the day the rock falls down he has to go back and push it back up again every day that's his life forever that's what life is like in greek mythology no mention in the telling uh what sisyphus's skin color was I don't know what that means for the future film to

1:37:59be made um I think that my views have changed on this a little bit you know I used to say I used to get it I used to be pro camu on this um he was trying to make the point that um sisyphus can be happy if he makes happiness out of the situation that he's in that it's not about the physical setup it's about your inward mental attitude toward the physical setup and you know existentialism um as we talked

1:38:30about with sky cleary and others here on the podcast has this big emphasis on freedom and the freedom to choose things and you might think well sisyphus has no freedom whatsoever for sisyphus is just pushing the rock up the hill over and over again and camu is saying well sisyphus has the freedom to be happy about it to take pride in a job well done of pushing the rock up the hill and okay I get that you know okay I mean I sort of get the argument but I think that what is special about the real world is that we

1:39:01have a lot more freedom than that okay almost all of us you know once we're once we've lost our freedom by being put in jail or whatever then we don't have it but in our everyday lives those of us who are not too constrained by the state or whatever have a lot of freedom to do things there's an infinite number of actions one could take at any one moment of time and it's kind of overwhelming and I do think that that sort of down-to-earth kind of freedom is also very happy so sorry is also very very important for happiness so what I would currently say is I don't have to imagine sisyphus

1:39:35being happy like if sisyphus is happy if sisyphus has the mental strength and fortitude to find happiness in the task he is forced to do over and over again then good for him I'm very much on his side and I approve and admire it but if he's not happy about it I totally get that too Tyler Briggs says throughout your career have you ever been captivated by an open problem in pure mathematics such as the Riemann hypothesis or the Collatz conjecture to the point where you

1:40:07dedicated concerted effort toward exploring it even if it sat outside your direct research in physics uh no not really I have done research physics oriented that did in sort of involve high level math but not even usually most of the physics I've done has sort of just borrowed math that already exists which is what most theoretical physicists do uh it's the rare people who are the um Ed Wittons and Paul Dirac's of the world that really have to invent new math for their physics um but I have you know

1:40:42calculated some homotopy groups in algebraic topology and done some work with free variable loop equations and things like that uh because there was some physics motivation I've never been truly motivated just by a math problem I think it's cool life is short you got to pick the problems you're interested in and the math problems that interest me most interest me most are those that have some relevance to the physical world anonymous says in your recent two-part solo episodes you briefly touched on the prospect of models that assume the gravitational constant g to be variable

1:41:16something you didn't seem to humor was assuming c to be variable that is that one imagined the speed of light to have been appreciably variable in the early universe could the acceleration of the universe then appear as a pure artifact of a systematic misinterpretation of deep space redshifts well it kind of doesn't work the idea of having the speed of light be variable it's an obvious question to ask but very quickly you realize the speed of light is just a conversion factor from how we measure space to how we measure time and vice versa it's a joke but it's true you can always set the speed of

1:41:51light equal to one no matter what it is doing so what does it even mean to let the speed of light be variable compared to what how are you supposed to measure it even the Newton's gravitational constant you know the it is also a dimension full quantity and you can set it equal to one if you want but it only appears in one place in the equations of motion of physics in Einstein's equation and so you can sort of put a scalar field there where Newton's constant appears and basically the variations in that scalar

1:42:26field have the same impact as it would to quote unquote let the gravitational constant vary the speed of light appears all over the place in the equations of physics so what you mean when you say the best thing you could possibly mean when you say the speed of light is varying is you're going to put some field some scalar field precisely everywhere the speed of light appears and nowhere else so that everything changes in lockstep so it looks like everything is constant except the speed of light is

1:42:57changing now you can do that people have looked at that uh Zhao Magagio in particular has done a lot of work on these things they don't seem especially promising um you know to me again i i say this a lot there's a lot of great ideas out there you can't pay attention all of them you have to sort of pick and choose what you're going to work on something has to be promising in some way for me to say like okay i'm going to put enough effort in to really understand the details of this kind of proposal to me making the speed of light vary never seemed that promising in the first place

1:43:29jennifer lecomte says what are the topics you enjoy teaching so much that you look forward to those topics each time you teach the class oh you know there's there are many of them in fact i think it's the opposite of the classes i teach i would say that most of the topics are ones that i really really like you know in the physics classes there are absolutely places where you hit something that you just need to do because it's your duty you know if you're teaching general relativity you have to teach the symmetries of the

1:44:03remont tensor what it means to symmetrize and anti-symmetrize and things like that if you're teaching quantum mechanics you need to remind them how to diagonalize a matrix or solve some special functions equations for hermite polynomials etc like this is tedious angular momentum clepsch-gordon coefficients there's there are topics that are tedious and you have to do them in the philosophy classes there are topics that are tedious for me in particular and i have to do them but i would say that 80 percent of the topics that i teach in a class are things i'm really enthusiastic to teach you

1:44:34you get to choose what you teach right so it's not completely arbitrary it's not completely uh surprising that that's the case um you know i did uh last year when i teach when i taught quantum mechanics i had a little bit of fun teaching them rigged hilbert spaces which is a technique for making sense of the fact that things like states of definite position aren't really part of hilbert space in quantum mechanics so there's this advanced mathematical technique to make it all make sense

1:45:05some of the students liked it some of the students really didn't like it at all they're like this is not going to be on the exam why are you doing this so i have to uh i have to alter my teaching strategies to fit the modern student mindset that i just want to know what's going to be on the exam balachandran says i recently read that electrons and heavy atoms like gold move at relativistic speeds which alters their chemistry and gives gold its color for example while i know electrons aren't literally tiny balls zipping around i still struggle to visualize what velocity actually means for an

1:45:36unmeasured spread out wave function how should we physically conceptualize things like velocity on the electron field when no measurement is taking place well i'm totally on your side on this i would you'll never hear me say that electrons in heavy atoms are moving at relativistic speeds because to me electrons are not little dots right they're wave functions or they're part even of the wave function of the universe even better and in an atom those wave functions are stationary they're not

1:46:07evolving okay nothing is moving when people say that electrons and heavy atoms are moving relativistic speeds they have one of two things in mind one thing which is entirely disreputable is to think of well if the electron had been classical what speed would it be moving at and the answer is close to the speed of light like who cares about that it's not classical in any way the other is that if you were to do a measurement of the speed of the electron or the momentum of the electron would it be relativistic and

1:46:41maybe the answer is yes but who cares you're not doing a measurement on it so what difference does that make there is a respectable thing you can say the respectable thing is not that electrons are moving at relativistic speeds what the respectable thing is is that non-relativistic approximations don't work well anymore so when you do the schrodinger equation as you know if you listen to me talking in these podcasts a lot there is sort of a big abstract version of the schrodinger equation

1:47:11that is perfectly able to handle relativity and everything else but there's also the simple non-relativistic version of the schrodinger equation that schrodinger himself wrote down in his very first paper and that is applicable to the non-relativistic limit that describes particles moving slowly compared to the speed of light for example in the classical limit so when you have atomic orbitals in gold or other atoms they can be outside the non-relativistic limit so you have to take into account relativistic

1:47:48corrections to the shapes of the wave function and the energy levels of the wave function so that's entirely respectable to say that to say like you need to take relativity into account to get the energy spectrum correct for these atoms that's true but don't translate it into your head as saying that the electrons are moving close to the speed of light christoph radomsky says quote it's just a theory unquote some science denier deniers say not understanding that theory is a well-established hypothesis backed up by strong evidence i feel uneasy when scientists misuse this word when talking about

1:48:22hypothesis hypotheses of various credibility unfortunately you also did that at least once when relating to uncertain hypothesis that's why i came up with some idea do you think it would be useful to introduce a hypothesis credibility level system by this i mean some well-established measurable system that would let us say this hypothesis is level three credible which would actually mean the credibility of it is within some well-described range uh so no i do not think that's a good idea and i did not make a mistake when i was speaking myself i think exactly the opposite of

1:48:54what you're saying here i think that words mean their uses and you have to understand how words are used scientists mostly understand this but there's some certain non-scientists who think that there's this hierarchy of credibility between conjecture model theory law whatever that's just not true that's just not how the words are used nor is it what they mean all of these words are used essentially

1:49:25interchangeably by physicists by scientists more broadly and that's fine in fact very often you have things that are super duper well established like the past hypothesis which is a hundred percent established or as close to a hundred percent as you can get given you know a tiny little bit of credence otherwise but it's still called hypothesis whereas newton's laws of motion are known to be false because we know that classical mechanics isn't right bode's law is the name given to this

1:49:57relationship between the distances of planets around the solar system which is a hundred percent crazy wrong right but it's still called a law so that's okay the the correct answer to this question is not let's change language so that the words mean different things so that you're that you're immediately telling people your level of credibility by what word you use it's just to tell people what level of credibility the concept that you have actually deserves you will notice if you had tried to have some

1:50:30system for assigning credibilities to different hypotheses that people don't agree on what the level of credibility is so it's going to be impossible to actually make that an objectively statable fact isaac osterbur says do you think it is better if a graduate student has a concrete set of topics and possible experiments when applying to a phd or is it better if they are more open to whatever work a research group has funding for does receiving a fellowship change that answer well uh this is an

1:51:00excellent question a super important question to be asking if you're a prospective graduate student i can't speak very directly for experimentalists because they live in a different world than i do in terms of funding and what needs to be done in the lab and so forth but i actually for whatever reason i've been asked this question or questions like it by undergrads uh more generally uh recently and so i have the following idea which is that as an incoming graduate student there's sort of a happy middle ground you should be looking for it looks bad either to um graduate school uh admissions

1:51:37committees or to prospective grad student advisors if they ask you what you want to do and you say i don't know like i'll be able to do anything like that looks bad that looks like you haven't really thought about physics and you're not really passionate enough about any particular thing but it also looks bad if you say i want to write this thesis i want to write this paper i want to investigate exactly this thing that makes it look like you're not open to taking guidance from the department you're in or from your prospective advisor an advisor is going to be looking for students who are passionate about

1:52:11a relatively specific area but willing to learn about what is going on in that area and adjust their research agenda accordingly that's at least true for theorists for experimentalists they're generally going to have a very very specific idea about what experiments need to be done what needs to be done in the lab etc so i think that the best thing to say is i'm excited by what is going on in your lab and would like to be part of it lars kruger says i'm fascinated by the idea of hidden sectors in

1:52:43particle physics how likely do you think it it is that dark matter is either one of multiple types of particle of a hidden sector that does not otherwise interact with normal matter um yeah i think it's a fascinating idea i'm a little bit on the fence you know i've written papers about the idea i wrote i wrote um papers with various people various collaborators about dark radiation so charged dark matter but the dark matter is charged under a new kind of electromagnetism that only interacts with

1:53:14dark matter not with ordinary matter so it's not ordinary electromagnetism it's dark electromagnetism and you have the dark photon dark magnetic fields the whole bit you can even imagine dark atoms and things like that um i think it's worth exploring because it might be true number one and that's always a good reason to explore it and number two maybe by exploring it you're led to realize that there are some new phenomena that you might not have otherwise imagined if you didn't think about it and i think you know what we looked at were truly massless dark photons just just so you know if you hear the phrase

1:53:50dark photon out there in the literature is more commonly assigned to ideas where you have a photon-like particle that does have a mass so i would call that something like a dark z boson but i'm not the emperor of physics not everyone listens to me there just so you know um i'm there's no evidence that this is right okay uh some of these ideas are chased down because they lead to interesting experimental consequences i think that's an excellent motivation for chasing them down because a theory investigated very carefully can let you realize there's an experiment you wouldn't

1:54:27otherwise have done and if you do that experiment you might see the thing you're looking for and therefore uh become famous and discover something new about the universe and you have to do the theoretical work first but if i were to place bets on whether or not the dark matter sector is actually complicated i would bet that the chances are pretty small and the reason for that is just because once you get complicated dark matter sectors it's easy for it to be noticeable it's easy for there to be interactions and you know couplings and different dynamics which we might have very well

1:55:01noticed already it's also easy to avoid them don't get me wrong but in the world of complicated dark matter models many of them are already ruled out by the fact that we haven't noticed anything interesting about the dark matter dynamics in yet other words the dark matter acts exactly as if it would act as far as we know if it were just a single particle no interactions nothing interact interesting going on so i think that's again the way to bet we should change our credences if we find

1:55:31any data the points otherwise mike bishop asks a priority question it's been a while we haven't had a priority question but again once per your life you're able to ask a priority question i'll do my best to ask it answer it he says is your undying patreon gratitude subject to cantor's diagonal so i think that your priority question needs to be phrased a little bit more clearly because i'm not quite sure what you mean what i am going to guess is meant by this is the word undying which maybe i've used i'm not

1:56:03sure uh implies a kind of infinity right if something truly never dies and time itself goes on forever then the gratitude must go on forever cantor's diagonal is uh georg cantor's way of proving that there are different kinds of infinity right that there is the countable infinity the uncountable infinity and so forth basically you can't put the number of let us say irrational numbers in one-to-one correspondence with the number of rational numbers because there are more irrational numbers than rational numbers

1:56:35so um no my i don't think that my gratitude is truly undying i think that's a rhetorical flourish therefore whether or not it is a countable infinity of gratitude or an uncountable infinity is not really an answerable question sorry about that henrik jacobsen says let's say we find a strong unified theory where a lot of things fall into place neatly and perhaps with independent evidence speaking for it too let's say it's also predicting an inevitable and high probability of vacuum decay and therefore is dismissed but with the many worlds interpretation could this theory

1:57:09survive and would the evidence for it even lend credence to a many worlds view any observer must after all be in a branch that is not yet decayed no matter how thin those branches get so i think this is a decent question that i'm not 100 sure i have a simple answer to because my views on how to use anthropic reasoning have been changing a little bit so i think that the short answer is um it wouldn't be very good evidence so just to just to back up and to help everyone understand what's going on here

1:57:42um if you it's it's not that hard to contemplate theories of physics where the vacuum state that you're in at any one moment is unstable basically you can have a bubble of a different phase of the quantum vacuum that would have a lower energy and there is a probability per unit space i should say per unit volume and per unit time that such a bubble spontaneously appears and because it has lower

1:58:14energy this is the true vacuum bubble and our vacuum that we live in is the false vacuum so that bubble of true vacuum would expand at nearly the speed of light and if many bubbles appeared around us they would take over and um wipe us out basically so would so that the idea is you're comparing two theories one in which um you're you're comparing two different ways of thinking about quantum mechanics

1:58:44a single world theory which says that that bubble nucleation is truly stochastic and just unpredictable and a many worlds theory which says that really there's many different branches of the wave function some of which have the bubble here and there and others of which don't um so would the fact that we live in the universe and have not yet been wiped out by a bubble of true vacuum be evidence for the many worlds view because the probability of getting wiped out might be very high but in the many worlds view there's at least somewhere in the universe where it hasn't happened yet okay um i think it's

1:59:21tricky it's very tricky because you know in the same view you want to compare the probability that someone like you could exist somewhere in the universe what is true is that in the many worlds view in the many worlds version of this story um you somewhere someone like you could definitely exist in one branch of the wave function of the universe whereas in the single universe story if there was really a high probability of all these bubbles being created and wiping us out then there would be very small probability that someone like you could exist fair enough but there's a special wrinkle

1:59:55with quantum mechanics right which is that not all of the worlds count equally if the amplitude for the world was in which you could exist is very very small then in some sense only a tiny slice of you exists or a version of you exists that doesn't count as much as a version of you that exists in just a single universe would count if you don't believe that way of thinking then you can't get the born rule right in many worlds quantum mechanics so my inclination is to say that it's not evidence

2:00:28in favor of many worlds but i'm not a hundred percent strong on that i've not really thought it through all the way so i think it's a little bit of an open question by the way i should say that the very fact that we're still here now is evidence that there is not a strong probability of the vacuum decaying indeed uh because if it if there were a strong probability would have decayed a long time ago we're right on the boundary where if it's going to decay at all it better decay decay soon otherwise we're in a regime where it the phase transition does not percolate as we say even if

2:01:04bubbles of true vacuum come into existence there's more and more ordinary false vacuum growing with time and you never completely complete that transition nelita s says when physicists say that particles are really excitations of quantum fields what picture should someone actually have in their head is there a mental model that's accurate enough to build intuition without being misleading um maybe not you know i think i i do talk about this kind of issue from time to time and i think i have a pretty consistent take here which is that

2:01:38it's super useful and helpful to have images pictures visualizations in your head when thinking about things going on in physics but it's never the point it's never the thing you should be aiming for because ultimately the equations are what tell you what's really going to happen and that's because pictures are a little bit floppy and manipulable and equations are just clean and crisp and you can't argue with them sometimes in modern physics you have things happening for which there's no picture

2:02:11for which there's no easy way to visualize you know when i say that the quantum state of a field theory consists of imagining the space of every possible profile the field might have and assigning a complex number to that which is the amplitude for that that profile that that shape of the field throughout all of space time throughout all space that's hard to visualize like you can have a picture in your head like of a little two-dimensional field vibrating up and down and

2:02:45then a little arrow pointing to the complex numbers or something like that but it's really not at all what's happening in this space we're trying to visualize so you know if you if someone says a particle is a vibration or an excitation in a quantum field if you want to think of a little vibration in a two-dimensional portrait of a field go ahead it's just to give you a warm and fuzzy feeling it doesn't really help you build that much intuition aaron fisher asks a priority question he says does

2:03:17the positron have its own field as distinct from the electron field in quanta and fields you explicitly write of the positron field page 210 as separate from the electron field but ai is very annoyingly confident that this isn't what sean meant and that positrons electrons in fact do exist in one field the electron dirac field well that's the thing about the ais is that exactly where questions become slightly subtle is where they're the worst that they're not good at subtlety they're very very good

2:03:50at conveying information for which there's a complete consensus about what the right way of talking is so the answer to the question is there is a single field that includes positrons and electrons and in fact it includes the spin-up part of the electron the spin-down part of the electron the spin-up part of the positron and the spin-down part of the positron this is the four component dirac field okay but the components are different they're separate things and indeed you don't need to use dirac notation to write

2:04:24down fermionic fields there are two component versions of the things you can write down but the more important thing is the positron in a correct representation in an appropriate representation of the dirac spinners the positron is represented by different components of that field than the electron is it's like saying the x component of the electric field and the y component of the electric field i can talk about them separately i can talk about the x component of the electric field no one's

2:04:57stopping me from doing that or i could talk about the electric field as the combination of all three components x y and z right no one is stopping you from doing it either way when i talk about the positron field i'm just talking about the components of the four component dirac spinner that represent the positron there's literally nothing whatsoever wrong with doing that and it was and what i meant was what i said jeffrey seagal says in the last ama and responding to nigel benjamin's question about laplace's demon and when a uranium atom undergoes fission you said that in many worlds

2:05:32laplace's demon would be able to say when the atom would undergo the fission could you explain this further the probability of fission is a continuous function and so in many worlds i would have thought that there would be constant splitting off of worlds as the fission occurs as the various times in proportion at proportion sorry at various times in proportion to the probability function um yeah i'm not sure what i said i never remember what i said um it's certainly not true that laplace's demon simply in a many worlds context knows when something that is a quantum um uncertain event

2:06:10is going to happen what laplace's demon would know in this very very hypothetical situation where laplace's demon knows the entire wave function of the universe is the evolution of the wave function of the universe so it knows the set of all possible worlds and the set of times when everything happens in every possible world okay that's what laplace's demon knows so you can put that into whatever question you want to know you know whenever you have an infinite infinite dimensional hilbert space so you have something that is smooth and continuous and there really is an

2:06:42infinite number of worlds out there counting the worlds is something that is not a well-defined kind of thing to do and saying when exactly something happens is not a well-defined thing to do either but this version of laplace's demon would know the total set of everything that could happen in all the worlds sonali says could you please explain the equations predicting a cyclic universe proposed in your recent paper in simple world simple words understandable by a non-physicist well the only equation is the schrodinger equation really that's the point and i can try to explain

2:07:16it i can i can try to explain the relevant part of it so the schrodinger equation is the equation that says how a quantum state evolves with time and it like we said it applies to everything relativistic non-relativistic etc the specific context in which we're looking at it in the recent paper is a finite dimensional hilbert space and that is important for the details but it's not really important today for answering this question what's important is that the schrodinger equation is linear now i know

2:07:46you want a non-physicist explanation but let me just use that jargon word of linear because it's super important here what it means is that the schrodinger equation just says you tell me the value of the wave function being operated on by this operator called the hamiltonian and that directly tells me the rate of change of the wave function so linear means if i change the wave function by a little bit the rate of change of the wave function also changes by a little bit it's not non-linear where

2:08:21a little change leads to a huge effect a little change leads to a little effect that's the whole point of being linear and the nice thing about linear equations is you can solve them exactly okay and basically what you do is if you pick the right starting point the technical thing to say would be an energy eigenstate a state of definite energy but the point is the right kind of state you apply the schrodinger equation to it all it does is there's a little factor outside e to the i omega t

2:08:53so e to the i omega t means that there is a complex phase that goes around in a circle in the complex plane e to the i omega t is a complex number that always has length one it could be one or it could be i the square root of minus one or it could be minus one or it could be minus i or it could be the circle on which all those things live the basic point is that if you solve the schrodinger equation every single state of definite energy doesn't change its shape all it does is have a

2:09:26complex phase as we call it outside that goes in a circle at a definite frequency and that's true for any system you want to look at in all of quantum mechanics you can always solve the schrodinger equation exactly by saying that in a state of definite energy the only thing that ever happens is its complex phase outside changes at a constant rate and what that means is that when you have a state that is not a state of complex of definite energy you can consider it a superposition of

2:10:01different states of definite energy and they each separately have this complex phase that rotates but not at the same rate the rate of rotation of that complex phase depends on the energy of your state so all of evolution in all of quantum mechanics comes about from interference both destructive interference and constructive interference between different parts of the wave function evolving at different rates and so that's the equation that we have in our paper the schrodinger equation

2:10:35with a finite number of states with definite energy they're all evolving at slightly different frequencies and they sort of beat against each other just like any other kind of wave can interfere or um or so yeah can constructively or destructively interfere i should say and so that's the whole trick the whole trick is there's a finite number of states out of which you build the wave function of the universe they each just sit there rotating and if you wait long enough they will come back to the same relative

2:11:05phase that they had in the beginning and we call that moment the big bang or the big bounce in our model i have no idea whether that was um understandable to the typical non-physicist but you know it depends on what you want if you want me to say like an even simpler thing i'll just say we solved the schrodinger equation and the schrodinger equation in a finite dimensional hilbert space has the feature that you will come back to either exactly or very very close to where you started there's nowhere else you

2:11:35can go you don't have an infinite amount of room to move so you can solve that equation exactly and find yourself in a cyclic universe tis jansen says i've recently been looking into qcd su3 symmetry the eight gluons and so forth with some help of ai su3 as i understand it is a subgroup of u3 expanding the su3 group to u3 i seem to be able to create a ninth gluon that is colorless and does not exist in nature i'm curious about why nature seems to work with the su3 subgroup but not the bigger u3 group

2:12:10and the implications of a ninth colorless gluon do we know of a reason or is it just because nature is this way yeah this is one of the questions that the five-year-old will ask you like why is the group of the standard model su3 cross su2 cross u1 rather than something else uh you're completely correct u3 is a bigger group than su3 it has nine uh generators which correspond to nine gluons in the particle physics way of doing it but roughly speaking you could separate it out okay roughly speaking the single colorless gluon um doesn't need to be related to the eight colored gluons it wouldn't be confined

2:12:47inside quarks and hadrons or whatever it could be there but it's not in nature like you said so in some other more grandiose theories of particle physics u3 might be part of the overall answer but there's a symmetry breaking that splits off that ninth gluon from the others that's entirely conjectural and hypothetical we don't really know i think the right answer the best answer the most believable and reliable answer is it just because it's just because nature is that way sorry about

2:13:19that okay i'm going to group two questions together one is from mac was a great cat who says in a world where there are things that are brute facts what's the chain that gets you from maybe the very low entropy of the universe is a brute fact to but i think there's probably a reason for it and i'm going to investigate and then james allen says how do physicists know when they've run out of layers of the onion what suggests that electrons are just electrons but that protons are composite particles

2:13:50if muons decay into electrons what makes us confident that a muon is its own particle and not just an electron wearing a very heavy electrically neutral winter coat i think that both these are perfectly good questions you know given some facts about the universe you can relate it to the su3 question we just asked given some facts you've noticed about the universe how do you know that it's a brute fact versus where you go further and the answer is there's no algorithm there's no thing you can do like to simply answer that question like oh yes now we know this is the most fundamental level that's never an answerable

2:14:24question what you do is you do science to it which means you construct different hypotheses and see how they work out you know the fact that protons and neutrons are made of quarks and gluons and electrons don't seem to be made of any smaller particles that has not escaped the attention of working physicists okay when you say like well maybe quarks are made of smaller particles maybe electrons are made of smaller particles maybe there's a relationship between electrons and muons of some sort of course scientists have thought about this they've

2:14:58worked really really hard to try to come up with a theory that number one would have those properties and number two would fit the data they have not been able to do it yet and maybe they will tomorrow you never know but at the end of the day that's the answer the answer is well where can you go with this what kinds of theories might have this be the case what can you do with them what predictions would they make how would i know whether they were true or not in the case of the past hypothesis the question

2:15:29can i come up with a theory that explains it is yeah i can i have done it myself so certainly can be done by people my theory might not be the right one but knowing whether or not it's on the right track is super important so it's worth doing um you know this is a running theme through these amas and through my podcasts knowledge is not foundational we don't just sort of find some facts that we know once and for all and build everything up from them we invent hypotheses and explore them that's how

2:16:01science is going to work shibs asks a priority question i have heard you describe more unlikely worlds thinner branches as not mattering as much i don't know what your ontology of mattering is here but it brought is it broadly speaking the fact that there are just more of the likely versions and therefore we should care about those more if so would you consider this a fundamentally utilitarian approach to mattering well uh it's not that there are more likely versions for example if you have a

2:16:32wave function that is a superposition of two possibilities and one of them has an amplitude square root of 0.99 and the other has an amplitude square root of 0.01 there are only two possibilities that's that's the entire trickiness of many worlds is that you can't get the counting that you need to get the born rule right just from counting the numbers of worlds the worlds don't count equally they count as much as the amplitude squared so 99 for this one 1 for that one so i use the word

2:17:07mattering just to be indicative of whatever matters to you so it might be the probability that you find yourself in such a world it might be how much energy such a world has it might be the utilitarian utility function that you have for such a world whatever you think is assigned to the word mattering goes along with the amplitude squared in many worlds i think that's a good motto to keep in mind to get you through figuring out how to think about this scenario cosmic debris says my friend and i argue

2:17:43about basketball versus football by which i mean soccer he prefers to watch football as he argues that basketball depends too much on physical characteristics such as height versus things like intelligence or dedication i claim that it is the same for football or chess for that matter is it it is just less apparent than height do you think there is a difference well look what i really think is it is silly to argue about what sport is better than what other sport if someone likes a sport good for

2:18:13them if they don't like a sport they that's okay too right i think that you can do a little bit of talking yourself into appreciating different aspects of different sports but who cares just enjoy it just like it and if someone else enjoys it differently that's also fine there's no question that basketball has the very specific situation where being tall is helpful right it's being tall is just so noticeable in a way that other physical characteristics are not quite as immediately evident

2:18:48for being a sumo wrestler being heavy is helpful up to a certain point right for being chess player there's various mental faculties that are useful but in all of these it's a mixture of things you know basketball players need intelligence or dedication also american football players weirdly enough offensive linemen are famous for needing to be super duper smart because there's a million different plays with many different moving pieces to all of them i suspect that soccer slash football also

2:19:25requires a whole bunch of physical characteristics it's true that various soccer players who have been world-class good have been relatively tiny would not have been great basketball players but still you need to be in pretty good physical shape and some of that comes from dedication but not all of it some of it comes from your genetics i think that's okay you know you can enjoy playing the sport you can enjoy being a spectator for the sport just enjoy it you can try to understand why you enjoy it like i said but don't tell other people they shouldn't enjoy it as much or they should enjoy this other sport

2:19:57even more polina vino says can you discuss the relationship between chaos theory and complexity theory yeah i can uh it's an interesting little slightly fraught uh relationship but they are both separate chapters in the upcoming book there was this feeling for a while that complexity happens at the edge of chaos so what does that mean so let's put it this way when you have chaos chaos is super duper

2:20:27well defined in a way that complexity is not to be honest we all kind of agree on what we mean by the word chaos if you have some dynamical system so that's a system that has some quantities that tell you what situation you're in right maybe their positions and momenta or something else some variables that you're tracking and you get chaos when you get a situation where at least in some regime there are cases where initially close trajectories deviate exponentially in time now it's not just they

2:21:01deviate exponentially because the space they're moving through is very very big uh in fact it's usually not that it's that there is a bounded region of phase space and so you can't just move off forever and ever like for example the planets in the solar system right the planets in the solar system only have a finite set of places they can be um but nevertheless the dynamics is technically speaking chaotic the time scale for the chaos to show up is very very large so it's not very visible um but in that small bounded phase space the rate at which the trajectories move apart

2:21:40is e to the some constant times time okay and this is quantified by the lyapunov exponents and that constant in e to the constant times time is the lyapunov exponent so if that lyapunov exponent is positive then at least one of them is positive then you have chaos that's what it means in at least some direction in the phase space or whatever it is that things diverge exponentially in time now um typically what happens and again i'm not super up on the mathematical theorems here so i don't know you

2:22:10know what implies what but i can say typically when this happens this um chaotic behavior you get an attractor in phase space so there's a region in phase space that different trajectories are drawn to the solar system which i just used as an example and many people use is actually a bad example here because it is a that's just a classical conservative system very often you find chaotic behavior in systems that are open systems or sort of not classical isolated systems that are conservative so

2:22:45in a classical conservative system like the solar system there are no attractors but in many chaotic systems there are attractors and they are what are called strange attractors strange attractors means it's not just like a circle or a point it is a fractal in phase space and so there's a close connection between but not a necessary connection right just a typical connection between chaotic behavior and fractals and fractals are sort of scale free something is happening at every length scale and that kind of

2:23:19scale free behavior is also characteristic of complex systems you got that so chaos is closely related to fractals which is closely related to scale free which is closely related to complexity i think that's the best you can do to draw a quantitative connection between chaos and complexity because otherwise they're different kinds of things chaos is saying that two initial uh initially similar conditions will diverge it's a statement about dynamical systems complexity is more

2:23:52about the idea that the that the system can sort of adapt well there's different again different kinds of complexity right complex adaptive systems happen when you have um the ability of a system to use information and to use that to adapt to the world around it arguably the more general conception is when you have many little pieces coming together to make a big piece but the little pieces are not individually designed like the parts in a car or a radio or whatever they're somehow individually

2:24:26similar pieces there's some homogeneity between the intrinsic nature of the pieces but they begin to serve different functions in the complex system because of self-organization so arguably the ants in an ant colony or the neurons in your brain sort of started out similar but found different roles in supporting this complex emergent phenomena so in that description you know words like chaos or even dynamical system don't directly appear um so there is a relationship but i wouldn't say that there is a

2:24:57close or very clear relationship for that matter cyclopropane says why is information treated like a conserved property like angular momentum or total energy what makes physicists bristle when considering the idea that information that falls into a black hole is destroyed forever well again as we were talking about uh before the way that science works is you propose hypotheses and you see what works information conservation is treated like an important deal in physics because it is a characteristic of

2:25:28our best physical theories right it wasn't first suggested as a principle and then imbued or embodied in the theories it's that first we invented classical mechanics and then much later pierre simone laplace noted that information is conserved in these theories so black holes are things that appear in general relativity general relativity is a theory that conserves information black hole evaporation happens because of quantum mechanics quantum mechanics is also a theory that conserves information at least until you make a measurement and collapse the wave function so the rough idea and there's a lot of

2:26:03subtleties here that i won't get into right now the rough idea is that general relativity and quantum mechanics individually conserve information so therefore we at least expect that information should be conserved in quantum gravity as well again it's not a derivation it's not a theorem it's an expectation that you can then go think about just like saying the low entropy of the early universe i could just take it as a brute fact and live with it or i could take it as a clue and try to explain it likewise the

2:26:33apparent fact that if you're not too careful about it information looks like it's lost in black hole evaporation might be a clue to learning something about quantum gravity so that's what we treat it as niles dar says i've always found it silly that hollywood depicted aliens as looking like us but the other day it occurred to me there might be something to it how much of the human body plan do you think is dictated by physics versus evolutionary contingency given the importance of seeing hearing etc if intelligence evolved independently on another earth-like planet would you expect something

2:27:06humanoid-esque um i truly don't know the answer to this one i mean on the one hand i am a big believer that there's a lot of variety out there in the world and we don't have a very good grasp on the space of possibilities so aliens could be wildly wildly different from us on the other hand i do respect the laws of physics and i am i've been very impressed by people pointing out that this or that feature of biological organisms had to be the way it is because physics makes it the most plausible way

2:27:38to do things maybe bilateral symmetry is an important thing it's not universal in advanced life forms but it's very very common wouldn't be that surprised to see it even in aliens um but we truly don't know i think that kind of thing you know the one very simple version example of this question is how how big should aliens be what size should they be right you know one thing even in um science fiction tropes that try to try their best to make aliens different compared to human beings they're usually

2:28:14around the same size right maybe a little bit bigger they're barely smaller actually um in science fiction and maybe there's a reason for that uh given physics right given the fact that volume and area evolve in different ways as you scale things up and down um but maybe the environment in which the aliens arrive is so radically different that the scaling is um dependent in well i guess the dependence on scaling is different in an important way so i right now in this form this stage of my

2:28:48understanding i would say i'm equally open and would be equally unsurprised if the aliens were really really different or if they were vaguely humanoid in appearance ed said stuff says i recently heard about a paper from a couple years ago that derived gravity from entropy what do you think about that idea and if correct doesn't that mean that quantum gravity is not necessary well there have been a bunch of ideas that relate gravity to entropy i don't want to say derived like how do you derive something from entropy that's like saying you're deriving

2:29:22something from the number two right like you might use the number two in your derivation somehow but there better be some more steps in there to actually derive something like general relativity um i think the most famous and successful version is from ted jacobson who has been working on what is called the einstein equation of state he points out that if you posit a relationship between entropy flux across the surface and the area of that surface which is a very natural thing to do you can derive einstein's equation right and so i've written papers about this also i think it's

2:29:56closely related to my whole program of deriving immersion space time from quantum mechanics and from entanglement uh it certainly doesn't mean that quantum gravity is not necessary like you still have quantum mechanics and you still have gravity i know that some people want to keep gravity classical that just seems entirely barking up the wrong tree to me quantum mechanics seems to be the operating system on which the world runs as far as we can tell i want to see how it can support gravity that's my personal preference moving forward if i'm wrong then i will change my mind joshua hillrup says what's your

2:30:33sleep routine look like do you tend to read or something in bed first or try to go to sleep right away do you have your phone nearby or keep it out of reach do you tend to have problems with insomnia well i do tend to read and most of my in-bed reading is done with my ipad actually because then you don't need to have a light on right i do put it in dark mode and whatever so it's not too bright not too many photons in fact fewer photons hit my retina from reading on the ipad than i would get by um keeping a light on in the bedroom i uh used to have some trouble getting to sleep once i'm asleep

2:31:07i almost never have trouble continuing to sleep uh maybe as one ages it becomes a little more likely that one wakes up at 4 a.m and has trouble getting back to sleep possibly that's a thing that can happen um but usually throughout my life it's been more like i have trouble falling asleep because my brain is racing because i'm thinking about something right so but what i've learned is don't try to go to sleep until you're really tired so that's why i will stay up reading or something like that until i'm really tired so that when i do finally put the ipad down and the head hits the pillow i fall right

2:31:41asleep and that's actually worked pretty well for me sandro stuckey says thank you for the excellent discussion with bonnie bassler it made me think about a discussion i recently had with someone about agency what criteria does a system need to fulfill to be considered an agent are bacteria agents are viruses can llms be considered to have agency are they more like a thermostat than say a dog what's your take on this well i think this is a deep and difficult question you know we discussed very similar questions in the recent episode with christian list and christian given his last name had a list

2:32:16of different criteria that he might use he was thinking about free will but agency is very very closely related to that i don't remember what the list is but it it seemed you know very natural he's sort of dealing with um concepts like you have control over something in your environment based on decisions that you make right and of course you need to define all these words that appear in the criteria but that that's okay that's just something you have to do um so i to me at least a minimal requirement for

2:32:50being an agent is having um number one some goals some uh preferences right some you know things you would like to have happen and in a sensible philosophically coherent way and the capacity you think about how to achieve those goals right rather than just you know a ball rolling down a hill is not an agent despite the fact that you can talk about it as if it wants to roll down the hill you really shouldn't talk about it that way and the evidence is if you stop it from rolling it won't

2:33:21fight against you right it won't just try to find a different way down the hill it just obeys the laws of physics agents have this ability to conceptualize the world in such a way that when their route to achieving their goals is stymied they can think about other possibilities right they can try other ways to do it i don't think that bacteria viruses or llms or thermostats count as agents by those criteria a dog does right a dog you can see being stymied in its desire to achieve its goals and sort

2:33:53of thinking not very cleverly but at least thinking a little bit about how to do better that's not very rigorous but i do think that's a minimal part of the story michael bright says on pages 61 and 62 of quantum fields you discuss a particle decaying into two entangled particles moving in opposite directions both detectable by the conservation of angular momentum i am imagining lots of similar particles close to each other also decaying into entangled particles flying off in opposite directions if there were two double slits set up on opposite sides of some region of space many of these newly

2:34:28entangled particles would move through them creating interference patterns on the screen behind if you were to put a detector on one of the double slits thereby collapsing the interference pattern to particle like patterns on the screen behind would the screen on the other side also collapse instantaneously into a particle pattern even without a detector if so entanglement is even cooler than i thought so the short answer the question is yes let me try to explain more what's going on i think it's a great question it's kind of it is pointing in the direction that entanglement is even cooler than

2:35:02you think so in the ordinary double slit experiment i send a single electron through it and you know this is i've been talking to people and realizing that they don't always realize this just send one electron through the double slits okay at a time it's not that you're sending many but in quantum mechanics an electron is described by a wave function that is a wave and so if that's all you do send one electron through the two slits that wave will interfere on the other side because part of it goes through the left slit part goes to the right slit and both of those parts will wave up and down and interfere

2:35:33with each other now when you observe the electron on the other side of the slits in some detection screen all you ever see is a dot so i want to you know clean up a little bit what michael says about seeing a particle pattern if you just send one electron you always see a particle pattern you see a dot right that's all you can ever see that's why in most descriptions of the double slit experiment what you do is you send one electron through at a time but you end up sending lots of electrons through

2:36:04so then you see many many many dots and what those many dots reveal is the existence of an interference pattern there are bands where there's lots of dots where the two contributions from the left slit and the right slit constructively interfere and there are empty spaces with no dots in them where there's destructive interference i mean that's hard to pull off in real life but that's the perfect theory version of this and then you know that if you wait close to the slits and have a detector there so you can see which slit it goes through you're collapsing the wave function you're

2:36:38removing if you see it go through the let slit you're removing the part of the wave function that would have gone through the right so on the other side there's nothing to interfere with and you no longer see interference patterns you just see a bunch of dots okay so what michael's asking is if i have two and the bit about two entangled particles you know that that whole discussion we just had was one particle not entangled with anything if i have a single particle like a higgs boson that decays into two particles then what you know is that those two particles in conservation of momentum

2:37:12tells you they must be moving in precisely opposite directions okay but because it's quantum mechanics you don't know which direction either one of them is moving in or even better if i'm going to follow my own advice the wave functions of those two particles don't move in definite definite directions they move out in basically spherical waves moving away from the initial decaying particle so what you know is that when you measure the location or the momentum of either one of those particles then you know that

2:37:43the direction the other particle moved and its momentum will be in exactly the other direction and if you do that carefully enough then what michael says will absolutely come true so you send out two particles you don't know what direction either one is going in but they're entangled so you know that when you measure them they will be back to back and one of them hits a double slit experiment and you detect which slit it goes through the left one or the right one and by doing that detection because the two particles are entangled with each other you are going to collapse the combined wave

2:38:18function of both of them and so since you've detected one particle going through one slit or the other you know that the other one was moving in precisely the other direction and therefore the other one is not going to go through two slits it's going to go through one or the other because you know exactly the direction it's going in if you did your experiment carefully enough and therefore even in the other side even if it's very very far away you're not going to see an interference pattern for those particles because you didn't let that particle go through both slits at the same time that's how it works that's how

2:38:54entanglement works and it is as cool as you can think of it being and i think that's a good lesson to take home tim gianitzos says scott aronson's blog mentions an error discovered by brent werness in the original coffee automaton paper you co-authored with scott he said in 2015 that a new version of the paper will be posted on archive within a few months but the version on archive does not list werness as the co-author or address the error is there an updated version anywhere and does this error invalidate your attempt to show that complexity rises and falls without additional assumptions that are inapplicable to our

2:39:28universe yes i've mentioned this before um this is just scott and myself being very bad there is a new version it's not quite done it's a few paragraphs away from being done but we had to bring upon bring on yet another collaborator um but it is very close to being done i've literally been working on it it's going to hopefully appear very soon it none of the conclusions spiritually change for those of you who don't know in this paper we looked at little two-dimensional models of cream

2:40:01mixing into coffee and we measured both complexity and entropy and you see entropy going up and you see complexity going up and then down but we made a mistake in the first version of the paper and so one of the models where we thought complexity would go up and then go down it just remained low the whole time that's completely consistent with what we're saying we're we're talking about when complexity can increase you know does it increase in this particular way and so we came up with an even

2:40:31better model what we call the tectonic model for coffee and cream mixing into each other and we did the calculation correctly and the the complexity does go up and then go down so the conclusions of the paper don't change it's just they are now being applied to different models and so um that's one of the reasons why we weren't working too hard to get the paper out but we really should get it out i'm glad that you asked the question because it's a little bit more motivation for us to finish that up

2:40:59eric olav chen says what is your current view on how one should rationally form credences under self-locating uncertainty specifically number one do you still endorse something like radford neal's full non-indexical conditioning and the epistemic separability principle you put forward with siemens and if so number two how do you see these two principles as relating to your preferred answers in the standard sleeping beauty problem well so let's be um clear here my my views have not really changed very much at all about that i think the wider question of how one should do anthropic reasoning

2:41:29my views are sort of changing a little bit and i'm trying to get them exactly right in the form of a paper i'm writing with isaac wilkins um but the general the points of view that um i like the full non-indexical conditioning which means you should not close your eyes and pretend that you are a typical observer in the universe that i still believe the epistemic separability principle is a much more narrow idea that only really applies to ever ready in quantum mechanics and it says that whatever credence you put

2:42:00on being on one branch of the wave function versus another should not depend on changes that are being made very very far away okay if the wave function is basically the same locally but different globally it should give you the same credences locally for whatever you're going to measure when you do an experiment um so that's it's much narrower in its application than uh fully non-indexical conditioning everett as we said just before is a special case that requires extra care when you

2:42:30think about self-locating uncertainty because you can't just count i'm a believer that when you have two observers who are more or less indistinguishable from each other in a single universe then they should be given equal credences if you don't know which one of them you are except if the universe you're talking about is the ever ready and multiverse because there the universes are not created equal um the standard sleeping beauty problem i really just think is a question of defining things carefully i think you have to operationalize it are you imagining some betting setup where you're

2:43:04going to bet after every awakening in which case you should probably be a thirder are you imagining some more ontological setup about the actual probability of a head of a coin coming up heads or tails maybe you could be a halfer so um i think that you need to tell me exactly exactly exactly what you mean by the standard sleepy beauty problem before i give you an answer to it sean sullivan says i've just finished reading stephen hawking's a brief history of time and noted that he and gregory laflam

2:43:35believed that the arrow of time would not reverse in a contracting phase of the universe how does this view differ from your cyclic interpretation in particular the paper stated that you have no idea why the universe would possess the low entropy starting point do you have any educated guesses or gut feelings why it may be this way well hawking's statements about entropy increasing or decreasing are in the context of a certain model his model of the wave function of the universe the hartel hawking wave function which has a solution to the wheeler dewitt equation and emergent time and

2:44:08blah blah blah blah our proposed cyclic model is in a completely different model where you have a finite dimensional hilbert space you don't have the wheeler dewitt equation time is fundamental blah blah blah okay so they're just two very different setups and one might be true or the other might be true um what i gotta keep saying about the recent paper about the cyclic universe is we're not putting it forward as the way the universe is likely to behave what we're doing is we're pointing out a loophole

2:44:39in something that other people have thought about for a long time quantum cosmology with a finite dimensional hilbert space okay ordinarily i would have said that such a scenario is just ruled out by the boltzmann brain problem no way out and in our paper we point out that there is a way out of the boltzmann brain problem in that particular situation it requires a bunch of fine-tuning and a bunch of sort of special pleading and things got to work out exactly right which is why i'm not suggesting that it's the most likely way the universe might be it's a possible way the universe might be and

2:45:13it's a very interestingly different way the universe might be than most other people's theories of the universe so i think it's worth paying attention to uh because its credence is not zero but small but the consequences would be very very big dale addison says what is your read on the kawai leonard trade situation how much if at all do you think the ongoing investigation factored into his decision to return to toronto so again for those of you who don't know why leonard um super good

2:45:45basketball player in the nba has been playing recently for the los angeles clippers but recently got traded to a team that he used to play for the toronto raptors the complication is that uh kawai's agent who i think is his uncle or something like that um is kind of a notoriously shady dealer and the owner of the los angeles clippers stephen balmer who made his money with microsoft um is also kind of known to shade a deal here or there himself and evidence has come to light that um they uh some

2:46:24some version of the word they came up with ways to circumvent the salary cap in the nba so the national basketball association has very strict rules on the total amount of money that can be paid to players by a team and it's obvious that one possible way to circumvent that is for the owner of the team if they're filthy rich balmer is the richest owner in the nba which is saying something to just say okay your salary is just this certain amount but my friends or my companies or my shell

2:46:55companies or whatever will hire you to do something not exceptionally onerous and will pay you on the side under the table to do that this is apparently exactly what happened with kawai leonard as has been uh discovered by pablo torre who is a podcaster sports journalist um uh who won a a pulitzer prize in fact um for audio reporting or something like that anyway they found documents that show pretty darn clearly as far as i can tell um that steve balmer and or his friends were paying lots of extra

2:47:29money to kawai leonard for doing nothing and so this was a year ago and it's kind of embarrassing that the nba started investigation still hasn't finished the investigation so i don't know what to think i mean i don't know whether that investigation factored into the decision to return to toronto or anything like that um it's not even at all clear if the nba does do some kind of punishment whether the punishment will primarily come down on kawai leonard or on the los angeles clippers i actually think that the clippers

2:48:02are the ones who deserve to be punished they're the ones circumventing the salary cap like if the player and their agent can get them money then you know maybe it's naughty but it's not you know the worst thing in the world whereas if the team is offering ways to circumvent the salary cap i think that's just very bad stevie cpw says if the pope agrees to be a mindscape guest what are some of the questions you would like to ask him um i haven't really thought about that i think the chances are small that the pope is going to be a mindscape guest you never know i'd still like for it to happen um i

2:48:36think that you know for someone like the pope pope leo what i want to talk about is the relationship between ontology and morality okay so basically the pope seems like a good guy as far as i can tell um but he's also the leader of the catholic church and the catholic church as institution has some beliefs that i think are pretty horrible and he has to go along with those beliefs because he's the pope okay so they have horrible opinions about gay people and transgender people they even

2:49:06have horrible opinions about women right women aren't allowed to be priests in the catholic church which is just so obviously a relic of ancient human beliefs rather than the word of god that i would like to know like you know how much of your beliefs about this stuff do you think comes from your innate humanity and your rational thought versus the doctrine of the church um and i would also of course like to know how he uh thinks about the relationship between science and religion and

2:49:38things like that you know i think a lot of people who are both good scientists and religious you know have this sort of compartmentalization in their brain where they say well science and religion is two different things i don't need to like fit them together other people have this feeling this sort of natural theology kind of perspective that no no doing science helps my religious beliefs and so i would like to know which side the pope comes down on on that i think there's lots to talk about honestly but since i have to do a single podcast every single week i don't spend too much time

2:50:10thinking about questions for people who are not the next guest that i'm going to be talking to peter van villa says you once stated that because of the winner-take-all system some people can go unrepresented for a lifetime if they happen to live in a predominantly blue or red county in europe i'm mostly happy with the proportional distribution that we have after elections at best it allows for substantial switches in policy between legislatures and to several parties having to meet halfway in order to obtain a majority at worst it can lead to negotiations dragging on for months without

2:50:42effective government a byproduct is the emergence of single issue parties while most elections are fought between traditional left-right factions social or liberal or religious what also exists is for example the animal party for animal rights 50 plus for senior citizens the pirate party against copyright the farmer party and so forth in the unlikely event that the united states should abandon winner-take-all system what types of possible ideological or new political movements would you expect or hope to see emerge from the ranks of the democrats and republicans that up to now remain

2:51:17underrepresented in the mainstream consensus um well i mean that's a good question you're asking a practical question that i'm really not best equipped to address um but it's an important one so for those of you who don't know um proportional representation is the following idea in a usual united states election we have some geographical region like a state or a congressional district and its majority wins right there's two candidates or maybe there's three candidates but the u.s has a constitutional system that strongly favors a

2:51:51two-party system so it's usually two candidates and then you vote and whoever gets more votes wins it's actually not majority rules plurality rule because if there are three candidates and whoever gets the most votes wins even if they don't get uh completely a majority and the problem with that obviously i mean you can imagine a a situation it's a little bit contrived but imagine that in all 50 states 49 of the electorate was in one party and 51 was in the other party then basically the country is split almost 50 50 51 49 but

2:52:27the legislature you end up electing is 100 from the 51 party right so this kind of mechanism does not result in a fair representation of the actual opinions of the electorate proportional representation which can happen in different ways but the most straightforward way is some sort of party-based proportional representation where in each geographical area you vote for a party americans hate this idea because americans don't like political parties and you know they've been trained against them since

2:52:59the federalist papers but uh in other countries they don't have that visceral anti-party reaction so you say i'm going to vote for the democrats or republicans or whatever and there might be there will generally be more than one representative from each geographical area so if you have let's say 10 representatives from a certain geographical area and 40 of the vote goes to one party and 60 goes to the other one then one party gets four representatives and one gets six okay and the

2:53:31political parties then decide and usually they will advertise this ahead of time but in principle it's their choice however many votes we get here are the individual people we will give the seats to okay so a lot more power in the hands of political parties in that kind of situation but also much closer representation to what the actual people want in in principle um so in in general it's a better system and political scientists at least think that this is a much better system than uh

2:54:04plurality vote or first pass to the post as it is sometimes called now there are downsides you know these weird little parties uh can absolutely get represented in the legislature and i i don't to be honest i don't understand why that's true and this is why i'm reluctant to actually give you a direct answer to the question um i can absolutely understand that let's say you think that animal rights is the single most important thing so you think that you're going to vote for the animal rights party but the obvious problem with that is that most votes that a legislator will take are not about

2:54:41animal rights okay so even if you think that animal rights are the single most important issue you should be voting for a party that agrees with you on that issue and hopefully also agrees with you on other issues because the other issues are going to come up you know i mean i would think that there would be some other party that would say we're in favor of animal rights and also we have all these other elements of our platform and that party would gain more votes so i'm not quite sure um how that why it is true that this kind of voting system gives rise to these tiny single issue

2:55:15parties um i do think that simply invoking the magical words proportional representation doesn't say that much by itself there's different ways of doing proportional representation there's the party like i said uh there's other ways of implementing it though so there might be some ways of doing it that could get rid of that problem or help it out this is something that that's now you've exactly gone past anything that i know very well so i'm thinking about it a lot because you

2:55:45know we're thinking about it's a coarse graining question right from the physics point of view you know just like you are coarse graining the positions and velocities of atoms to get temperature and density and things like that you're taking a microscopic description which is the preferences of every single voter and you're coarse graining them to a macroscopic description which are the people representing you in the legislature how best should you do that is an excellent question that i'm thinking about but i won't promise that i actually have all the right answers to that right now

2:56:16Ankar Sadikar says i recently started my first postdoc after finishing a phd do you have any advice for how to smoothly transition from being responsible for doing the groundwork like cleaning data running simulations to assuming a more mentor-like role in a team giving feedback suggesting ideas i still feel the urge to do all the things by myself but given my increased responsibilities it's not always possible yeah i know this is going to be another thing where different very very specific conditions are

2:56:46different you know i was never someone mostly cleaning data running simulations um i was coming up with ideas myself even as a grad student just not because i'm extra special just because that's the kind of physics that i do that's my job it's mostly coming up with ideas and then calculating the consequences of them i would say though that uh you're right to have the intuition that assuming a more mentor-like role is part of your job as a postdoc and it's also just a good thing to do um but even more

2:57:19than that i would say keep in mind that there's this sort of lagging education that you get as i like to think about it the things we want you to do as a postdoc are not the things we train you to do as a grad student and more importantly now that you're already a postdoc the things that we train you to do as a postdoc are not what we want you to do once you become a faculty member so i would not only think about what i need to do to be a great postdoc although there's that you should also

2:57:51think forward to what will i need to do to get a faculty job and then become a good faculty member and so it's not just being a mentor to those under you but really being an intellectual leader about what projects should be we be working on how can we make progress on them um the team as a whole might have some people who make progress faster than others how can we pick them up uh the ones who are lagging behind a little bit um how can we apply for money apply for grants you know um

2:58:24what conferences should we go to uh what speakers should we bring in who should we be collaborating with all of these faculty level questions you might as well start thinking about right now i have no easy advice on how to do it well these are all things that you got to get in there and do um to get better at so practice makes perfect in this case david kudeverdian says is it a sensible question to ask what the shape of a photon is say one emitted from an atom for example i've heard a lot about the shape of a

2:58:58hydrogen atom's electron orbitals spdf etc but i've never heard anything similar about an emitted photon well the reason you have not heard that is because those electron orbitals are confined not confined in the sense of quart confinement but they're bound states in the atom so they trail off to infinity but they trail off when you get far away fairly quickly so in a very realistic sense those orbitals are sort of stuck inside some region close to the nucleus whereas a photon isn't stuck anywhere you can put in a

2:59:35cavity right you can sort of seal it up a single photon and then there's something called cavity qed and then you can talk about the shape of uh it's not good to talk about the shape of a photon talk about the shape of the wave function of the photon that's what the orbitals are for the electron so in empty space the shape of the either photon or electron wave functions can be anything at all they're typically approximated by wave packets or plane waves or spherical waves generally if you have something

3:00:09like a photon that is emitted from an atom roughly speaking it depends on details about angular momentum and so forth but roughly speaking it will spread out in a spherical wave it will spread out in all directions and that's the closest thing that you can come to saying what is the shape of the photon which means that if you are observing a photon emitted from the sun then suddenly there was a wave function that spread out i don't know 93 million miles in radius around the sun that you just collapsed just by looking at it now in the real world probably that photon bounced off various things in the atmosphere

3:00:44so it's not quite true but you know in principle things like that can really happen henry jacobs says i've been working on a project to help grow activist movements in the likely event that certain people decide to meddle in the midterm elections however when demoing the project to friends i don't get pushback on the project itself but instead on the very idea that activism is effective of course i think it's effective but there seems to be a rise in skepticism after the no kings protest came up empty do you care to comment yeah i think that people are impatient and they shouldn't be i

3:01:19mean what what is what is the purpose of skepticism or the reasoning behind the skepticism after no kings protests um we don't have a king it worked right um but i think more importantly there are very slow moving variables describing the global opinion of people in a country or in the world that don't just change overnight but do get affected by the existence of demonstrations and movements and things like that i think that historically demonstrations and activist groups have been absolutely crucial

3:01:55in making things happen you know there is the george bernard shaw quote about how it's true that reasonable people know you can't change the world therefore all change comes from unreasonable people and i think that in a certain sense that's true you know a lot of people will in the world you know we have a lot to do um we have to worry about our own stuff about earning a living about you know our own families and whatever and it can be hard to devote time and energy and money to movements or efforts that

3:02:28don't get immediate payoffs but they're crucially important so people like you henry who are doing this are just absolutely central and if some of your friends don't get it just keep asking other people look for other friends you know to me it's like having sex and then the next morning you say well i don't see any babies here i guess it didn't work you know sometimes it takes time for things to pay off you have to lay the groundwork well in advance and it will eventually have a good outcome

3:02:58david maxwell says are you excited about the medium term moon plans not just going there but establishing a presence and developing a way to explore the solar system more effectively you know i wish i could be more excited than i am you know i'm someone who is a believer in exploring outside the earth whether it's the moon or mars or elsewhere in the solar system etc i think that very very long term that's going to happen it's going to be super important and there's a lot of benefits to it it's also super duper hard and i think that there's a lot of people who are just

3:03:31closing their minds and covering their eyes about how hard it is and they're sort of not really realistic about it and worst of all you know the whole thing has become kind of politicized in ways that are unpleasant uh the discourse around exploring the solar system is being dominated by a bunch of people who don't know what they're talking about don't want to do it for the right reasons and are unreliable in their predictions and their understanding of what exactly is going on so i'm both in favor of doing

3:04:04it the moon and elsewhere but also not at all trusting that it's going to be done well you know the the federal government um is the most likely place to get people having plans for doing something with the moon um because there's not going to be any immediate payoff even if it's private corporations that do it they are going to need to be heavily heavily subsidized by the government and i just don't have any faith in our current federal government to make good decisions about this so i like the idea but i'm kind of very lukewarm about the actual implementation

3:04:39in the near term chris mason says in your opinion what makes a good research question well that's a good question in it of itself um and it's going to be one where very different answers are perfectly reasonable you know there's different kinds of good research questions um some research questions involve embarking on decade-long projects building the right experiment and chasing things down and being very patient and assembling a team others are things you can do in a weekend right so there's

3:05:13no not going to be any one simple description of what makes a good research question i think that a lot of factors come in you know better than saying what is a good research question a better thing to ask is sort of what should i keep in mind when contemplating whether a research question is good or not you know the very down to earth almost too simple to be dwelled upon things are it has to be a question that other people want to know the answer to you know you're always losing if you're because i do this all the time this is how i know if your research question you're very fascinated by but nobody

3:05:47else cares right if you say the answer to it um you know they're like oh yeah i knew that or i'm not really sure why that's interesting you know when i wrote this paper with chris chaloux uh last year about what happens what do you see what does hawking radiation look like when you fall into a black hole and i've been fascinated by this question for decades and i knew that it would require an enormous amount of very technical calculation and i didn't quite have the stomach for it and eventually chris did and he did it and he deserves most of the credit for that and we found a result that makes perfect

3:06:20sense and is kind of intuitively clear after you say it but look i know that i've asked this question and talked about it to many many very smart theoretical physicists before we wrote our paper and none of them gave me the right answer and then once we came up with the right answer i explained it to very good theoretical physicists and they're like yeah i guess that makes sense i probably would have said that no you wouldn't have but okay if you want a question that actually gets people excited it has to be one that people recognize as an interesting question ahead of time and then it has to be one

3:06:54that you can do right a lot of questions sound good but you just don't quite have the either ideas or the technology or whatever to answer them effectively so that's very very simple-minded i mean the the third quality is that you better be interested in it yourself right so you better think it's interesting the world better think it's interesting and you better have the wherewithal to actually do it those are hard to find you know it's easy to find questions we don't know the answer to

3:07:25what what what happens very very very very often when you are a young scientist is that it's easy for you to find questions that you can answer this is more of a problem than you might think when you're an undergrad typically there aren't any questions that you can come up with that you instantly know how to answer otherwise you'd be writing research papers but once you got a phd now you're trained in one little area on how to get answers to certain questions and it can be way too tempting to simply

3:07:59spend time and effort on questions because you can answer them rather than because they're interesting so i think finding that dividing line is really really important i mean i i specifically explicitly shifted my research focus uh 10 or so years ago from questions i could answer about you know scalar fields and dark energy and whatever to harder questions that i think are more important that are more foundational and other people might not think they're important that's okay i'm old enough to just focus on what

3:08:31i think is interesting but young people gotta take the rest of the world into consideration

3:08:36the great deceiver says could an event be considered a complex system are there any theories on that out there i went down the jfk hole a few years ago and i kept thinking this has to be one of the most studied events ever and now you've brought some of the ideas of complex system sciences to me so it seems like a natural question can an event be studied as a complex system well i think the traditional answer would be no um in the following sense you know a complex system is something that

3:09:08itself has an evolution over time like you can ask questions like if i perturb the system in a certain way how will it respond right that sort of dynamical question is central to what we think of when we talk about complex systems events and i know that what you mean are the sort of everyday meaning of the word event not the general relativity meaning of the word event which is a point in space time points in space time are not complex systems you mean a happening in the world something that occurs through the build-up of some set of occurrences with some causal structure um the thing is that the

3:09:42event as a whole like even if all sorts of conspiracies are going on and all sorts of moving parts but the whole thing plays out it's done right it's there it's not changing you can't perturb that system and ask how it's going to change with time because it's already in the past so it might involve complex things going on but it is not quite the traditional notion of a complex system i do believe that there's many sort of different notions of complex systems and maybe system isn't what you want maybe

3:10:15you can talk about the complexity of an event even though it's not a system right you can apply the idea of complexity to many different things to strings to images to questions in computer science or whatever so i don't know if anyone has studied um sort of a way of quantifying the complexity of a process that has led up to an event but maybe they could do that ken wolf says in your talk with mark berman he made a distinction between directed or top-down attention and involuntary or bottom-up attention

3:10:49i couldn't help but thinking of this as a distinction between things that are productive and things that make us happy in the modern world dominated by economic thinking we like to think those things go together but this distinction seems to suggest they are inversely related we give we give up the game when we speak of having a happy productive life which implies the two things are distinct does this suggest that there is an inverse relation between productivity and happiness or am i reading too much into the distinction well i think you're reading too much into the distinction in this case um i would

3:11:19argue that things that there are some things that require directed top-down attention and can make you productive that also make you happy i mean it happens to me all the time right here i am making a podcast and if making the podcast didn't make me happy i wouldn't be doing it um there's other things like earning your uh beloved patreon support that that helps me do the podcast but i wouldn't do it if it didn't make me happy in some way and it absolutely requires some attention okay i don't think that's the right distinction i don't think that's the distinction that mark was trying

3:11:54to make um there might be some there's some way of thinking about these things which almost wants to sort of denigrate top-down directed attention like you're working too hard you should just live life in the flow in the moment from time to time like i don't believe any of that i'm sorry i think that's part of living a happy life but if that's all you did that i wouldn't i wouldn't be happy at all living life that way i think that happiness is much more about finding the right mix of when you're

3:12:28giving directed top-down attention when you're giving involuntary detention and when you're not giving attention at all okay um when you have those different kinds of things going on in your life other people will find happiness elsewhere some of them might find happiness purely in this involuntary in the zone kind of thing others are only going to get happiness out of directed top-down attention and you know i think all that's fine let people be happy in the way that they find happiness

3:13:00peter solfest says in the last ama you said that to an outside observer the particles across the event horizon can have negative energy which is how hawking radiation shrinks a black hole would an observer inside the event horizon see a positive energy particle or is the negative energy particle just a mathematical artifact used to describe the source of hawking radiation yeah the people inside the event horizon would see a positive energy particle the whole point of the discussion is people in different reference frames assign different energies to particles that's the least surprising thing in the world

3:13:34right even in special relativity without gravity two people moving at a velocity with respect to each other assign different energies to different particles the things that gravity and general relativity and horizons make possible is that that energy can actually go negative but to a person in the rest frame of the particle it will always have a positive energy graham snowden says what do you think the american scientific community could or should do be doing to push back against the relentless and increasingly

3:14:05effective attacks from the trump regime on the pace of science in the usa the place sorry the place of science in the usa well i think that you know the trump regime is in power right now and they're not open-minded like they're not going to listen to advice or anything like that i think that the american scientific community should do what a good politically engaged set of people should always be doing which is reaching the people who can be reached i think the american scientific community should make the case for

3:14:38the importance of science to the broader public and it should do it in many many different ways it should do it through tv shows and podcasts and books and events and any any possible way it can do it we have to spread the message of science and reason and the enlightenment and all of those things and we never are going to stop doing it it's not going to be something like oh we'll do it for a year and we'll win and then we can go back to doing research this is just part of life in a democratic society that you have to make the

3:15:11case for what you think is important and you know i don't think we've been especially good at that uh you know we had a good situation for much of the 20th century where the importance of science was simply unmistakable in some sense now it's even less on it's even more unmistakable it's less mistakable uh but nevertheless people managed to deny it because we've invented all of these mechanisms by people by which people can deny reality for an extended period of time eventually the price for

3:15:42that is going to have to be paid and this is why you get people getting measles and explosive diarrhea and so forth but in the meantime um a lot of people are just gonna keep denying science so you have to let some people be like that and reach the people who are reachable um we don't do a good job we don't uh value it as scientists you know we look down on people who do it uh we don't put systematic efforts into doing it and we're beginning to pay the price for that and it's not just scientists

3:16:13this is something that lots of people don't want to do don't want to spend time and effort making the case for the importance of what they do i think that we have to do that stuart haynes says when you decide to leave caltech for johns hopkins how did you negotiate the transition of your grad students was that difficult i don't have much of an answer to this because none of my grad students transitioned you know i knew that i was going to be leaving caltech before i did and also we had a pandemic remember like i left caltech in 2022 so you can do the math so i had already stopped taking grad students and my

3:16:48last uh caltech grad student ashmeet singh graduated during the pandemic in i think 2021 maybe 2022 i forget um and then i started picking up new grad students when i got to johns hopkins so i didn't actually have to go through that myself nor did anybody else it is a thing just so anyone out there who might be interested um when professors move from one place to another and they have grad students working with them it is often the case that they negotiate with wherever they're going to go can i bring my grad students with me and then there's a separate negotiation can i just literally

3:17:21physically bring them but they're still students at the old institution or can they join the new institution and it all the different possibilities work out in different ways it just depends on all the details so i personally didn't have to go through that jonathan cart said i recently saw ed copeland doing a video about reheating after inflation he talked about how the inflaton field would decay by a couple mechanisms perturbative and resonant and that would generate the particles we see today so my brain has accepted that heavy particles decay into lighter ones because they're in a lower energy state but i have

3:17:57no intuitive understanding or what for why the inflaton field would decay is it a similar lower energy state mechanism that i need to wrap my head around well remember what's a particle right what is a particle particle is a vibration in a field that's how quantum field theory works so the truth is that when the inflation sorry when inflation ends and the inflaton reaches the bottom of its potential it rocks back and forth in the potential it's sitting near a minimum and it's rocking back and forth gradually decaying

3:18:28in amplitude for a couple of reasons but you can interpret that field configuration as a set of particles since there's very little variation in the field from place to place there's very little spatial gradients the momentum of the particles is close to zero they're particles sitting at rest okay and there's a lot of them it's actually technically it's a bose einstein condensate of particles and if you want to think about the creation of ordinary matter and radiation quarks and electrons and photons and so forth during reheating you can if you want to just think of those individual inflaton particles as being

3:19:06heavy particles that decay into lighter ones that's it now there are subtleties that that picture doesn't capture because the field picture is more fundamental than the particle picture so the details that ed was talking about with perturbative and resonant mechanisms and so forth these are all details that are more clearly seen mathematically from the part from the field image rather than the particle image but if you just want to have an intuitive understanding of how does how do the quarks and electrons get made you can think of them as arising as decay

3:19:39um products from the inflaton particles themselves which are excitations of the inflaton field

3:19:48michael honey says there have been several mathematical conjectures disproven by llms in recent weeks are there similar conjectures in theoretical physics that might be amenable to llm investigation i could have grouped this i guess with the earlier question but roughly speaking no i mean i i i say that tentatively because the state of the art is improving very rapidly and maybe things are going to change but the nice thing about math is it is very clean and crisp to know when you have a disproof of a conjecture or even a proof that you could plug into a formal proof checking thing like lean

3:20:22like we were talking about before in science and physics you don't have that right if i say oh look i have a new theory for what the dark matter is prove it right the llm could prove a mathematical conjecture about that theory of dark matter but it can't prove that your model is the dark matter that requires experiments okay and llms are not very good at that so the kinds of conjectures we have in theoretical physicists in physics are not ones that are conjectures about the properties of

3:20:53mathematical axioms or postulates the word conjecture means something a little bit different in math and physics in math it means this statement may or may not be a provable theorem based on these axioms in physics it means this statement may or may not be a correct description of nature so it's a very different task that you uh it's much harder to use in llm to investigate that chris says the other day you mentioned your enjoyment of playing silly games on your ipad for a mental break over the

3:21:24years what have been your favorite games i think my favorite game over the years has been the kingdom rush series that i have on my ipad it's a it's a what is called a tower defense game so the enemies come through and you build towers to prevent them from getting to your kingdom or whatever it is a very silly game this is what i like about it is the game is good and there's a series of them so i i can play one and then whenever i want to play again i can play a different one and it's not just playing the same thing over and over again you know my goal for playing silly games on my ipad is not to do too

3:22:00much intellectual effort my intellectual effort goes somewhere else so you know a lot of games require an investment right like you need to like take notes and really understand the world at a deep level and get into it and get immersed and i love that idea um it's just not for me uh i i'm putting my intellectual effort elsewhere and when i'm when i turn to my ipad to play a game i want a break i want something i can sit down do for 10 minutes complete a task move on to something else i'll also play like traditional games backgammon poker um solitaire whatever um those are also things that i will play i will

3:22:38try you know i've tried various other kinds of genres but it's a very fine line you know you don't want to be too silly and stupid you don't be too effortful and intellectual and that is very hard for me to judge from the descriptions of the games on the app store or whatever so i have a difficult time figuring out whether i would actually like a game or not and that that makes me just stick to my old favorites anonymous says are there thought experiments or intuition pumps neutral to the interpretation of quantum mechanics that can allow us to understand entanglement or why multiple particle quantum

3:23:12wave functions are not separable by particle you know i mean short answer is i don't know i don't know it's a matter of what will satisfy you right um i don't think that there is once and for all a single answer to that my attitude is that you should really take quantum mechanics seriously for what quantum mechanics says and what i mean by that is instead of starting with the classical world and trying to describe it in quantum mechanical terms this is why people get in trouble with saying we can't know

3:23:49the position and velocity of a particle at the same time because of the heisenberg uncertainty principle instead of what they should say is there is no such thing as the position or the velocity of a particle in general there are certain specific quantum states that have definite answers to the question what would i observe the position or or velocity to be and they're not the same states that's the uncertainty principle but if you think of what is if you think of what is real as the quantum state

3:24:21itself rather than your observational outcomes and you understand that the quantum state of several particles is a single quantum state not separate quantum states for separate things that's not surprising at all like there's no difficulty in that um the the x y and z components of the location of a particle are not separate things they're part of one thing um then the fact that different possible measurement outcomes are correlated because of entanglement in in my mind is just like okay

3:24:56sure of course they are that's not that's not hard to see i think all the difficulty in understanding entanglement comes from thinking of the measurement outcomes as fundamental rather than the quantum state as fundamental and then if you start with measurement outcomes and work backward to describing them using a quantum state then entanglement seems really really weird and mysterious if you just start with the quantum state then i think everything becomes much easier to understand peter 42 says clocks run slower the

3:25:29stronger the gravitational field they find themselves in when we place a clock at the center of the earth the planet pulls on it equally from all sides so there's no net gravitational field does a clock at the center of the earth therefore run faster than one on the surface or does it run slower because it has the mass pulling from all sides that slows it down so clocks do not run slower the stronger the gravitational field they find themselves in clocks unless they're broken run at one second per second this is the kind of thing that i say over and over again and people kind of roll their eyes and like

3:26:00why are you bothering you know what we mean but questions like this are exactly why it is better to say the true thing than the false thing the true thing is the clocks run for one second per second no matter where they are the true thing is that you can only compare the total amount of time that has been measured by two clocks when those two clocks start at the same position and time in space time and go on journeys and end at the same position and and location and time in space time start at the same event

3:26:33and end at the same event the true thing to say is that if one clock starts outside a gravitational field outside a black hole or whatever and just stays there not moving and another clock starts at the same place and goes to visit the gravitational field and hangs out there and then comes back the one that hung out for longer in the stronger gravitational field will read less time than the one that just stayed home the way to remember it is staying home makes you always measure the more

3:27:07time it's it's the flip side of the shortest distance between two points is a straight line the longest time between two events is just staying home and not doing anything okay so it doesn't have any there's no meaning to the question how do we compare a clock at the center of the earth to a clock outside you have to start them at the same point and then travel and you'll notice that if one stays outside and the other travels inside to the earth it has moved through a spatially dependent

3:27:38gravitational field and then you can very easily ask the question what is the total amount of time elapsed and the amount of time elapsed from the clock that visited the center of the earth will be less than the one for the clock that stayed outside perfect example of where saying it correctly helps you understand what to predict copper nick says as a thought experiment let's assume that infinity is purely a mathematical construct and that the real world is finite in every way what interesting or significant things might that change if any with how you look at cosmology or

3:28:12theoretical physics i think this is a thing that people should be thinking about um i don't think that people have thought about it in any very careful way you know um there was this workshop organized by former mindscape guest clark uh justin clarkdown um a year or two ago i'm forgetting now uh but it was written up in quantum magazine that you can check out it was a by a bunch of people who are interested in ultra finitism or finitism i don't know how to even say it um the idea that

3:28:43mathematics should be based on just a finite number of things not an infinite number of things and you can do it right i mean you can invent a new system of axioms that make a finitist um arithmetic work uh and then the question is is that relevant to the real world and the on the physics side of things very few people take this seriously because quantum mechanics quantum mechanics does not say the world is made of like little pixels or anything like that it's just absolutely doesn't say that at all

3:29:16it says the world is made of quantum states and how many quantum states are there an infinite number even for a single qubit there are an infinite number of quantum states it might be a two-dimensional hilbert space but it's a vector space there are an infinite number of vectors in that two-dimensional hilbert space so i was invited to the workshop because i wrote this paper a couple years ago on could you discretize quantum mechanics and some other people had tried to do that before but they didn't do it in a very good way i thought and indeed i i this is a

3:29:50kind of an interesting thing i wrote the paper saying look you know it's you can if you do things in exactly precisely this way come up with a truly discrete and finite version of quantum mechanics but it requires a lot of what would look to us like fine-tuning and the real problem is it has a boltzman brain problem because there's a finite dimensional hilbert space and time would go on forever or at least it would be cyclic in some way and the more recent paper that i wrote with

3:30:21sakshi delani and nadia diachenko pointed out that there's a loophole there and in fact you can avoid the boltzman brain problem in precisely that situation so now i think it is possible and when i say possible i mean both mathematically logically possible and compatible with all the data we have of the universe as we know it that you only need a finite set of states to do physics in a reasonable way so i think that's very interesting again i don't think that there's any evidence that

3:30:53it's true i think there's certain mathematical difficulties in the whole thing um but it's allowed and i think that uh there's obvious benefits to it infinity can be hard to deal with it's hard to make predictions when there's an infinite number of possible things that can happen having everything be finite would make many many things much simpler so if we did have any evidence that was true it would be really nice and we'll have to see how that works out kevin's disobedience says did dirac accidentally invent string theory only to abandon it reading his biography i was surprised

3:31:28to learn that he once conceived of electromagnetism as quantized lines of force the opposite charges manifesting on each end i realize it isn't open and closed vibrating strings that are giving rise to fundamental particles and that it doesn't require extra dimensions negative cosmological constants supersymmetry anything like that but i'm am i wrong to think that this sort of approach to quantizing a field theory is akin to string theory or is this octagonal i think you mean orthogonal or maybe it's a joke to the whole project um yes and no so you can think of what dirac did as a deep deep precursor to string

3:32:02theory he didn't invent string theory and in particular if you want to think of a positively charged particle and a negatively charged particle as being connected by a quantized line of force the thing is that line of force has no energy density whatsoever it's completely a mathematical artifact so that's very different than the fundamental starting point of string theory um that there's a you know string theory thinks that the physical real stuff are the strings dirac never really thought that he thought it was a way to quantize gauge theories in fact he was most interested in i'm not even i don't i'm not

3:32:36even familiar with him ever talking about electric charges that way he talked about magnetic charges that way and that's a very famous construction called unsurprisingly the dirac string those of you who know a little bit about maxwell's equations maxwell's equations for electromagnetism might remember that there's an asymmetry there because there's a term that represents electric charges but no term that represents magnetic charges there are no magnetic monopoles in ordinary maxwellian electromagnetism so

3:33:08of course again every physicist is going to think well why not maybe we could make it work you know and dirac is smarter than the average physicist so he did make it work and one of the big obstacles to making it work was that we have this idea that the electric field the magnetic field are not the fundamental variables right there's something called the vector potential field from which you can derive both the electric field and the magnetic field but if you believe that what you find is that it's an

3:33:39immediate mathematical identity that there cannot be magnetic monopoles that just the math doesn't allow you to do it so dirac figured out how you could do it by having singularities that you dealt with in a very delicate way etc etc later um so we have the dirac monopole direct magnetic monopole connected to the direct string which is sort of a mathematical artifact later the whole thing was made much more respectable in spontaneously broken gauge theories where you can have um the symmetry that

3:34:10was spontaneously be broken be restored at the center of a magnetic monopole and you don't need strings or singularities or anything like that so dirac did important work which did eventually feed into string theory but he was not suggesting that the fundamental stuff of nature is made of strings in any way so he should not get credit for inventing string theory okay the last question comes from matt which is what are your thoughts on the 76ers after the jalen brown trade and the new signing of lebron now i know that i said in the introduction i wasn't going to talk about that but this is the

3:34:44last question we're going to let ourselves have some fun now i don't feel constrained what i wanted to talk about it was an obvious thing to do to talk about um the sixers in the intro to the podcast but i know that it's not everyone's thing so and i could easily talk about it for a very long time so i thought i would put it at the end and i'm giving it to matt's question but many other people asked related questions to this they will all you should all consider yourself getting credit for this question so where are we um to lay the groundwork here um you know the sixers have been there's a long

3:35:18history here i could literally write a book books have been written in fact so i don't need to write the book but um there was this famous experiment in the nba uh where the ownership of the 76ers fired their general manager and hired sam hinkey who was a um assistant general manager with the houston rockets and he famously he was very driven by analytics that is to say we should really look at the data really learn how to figure out what is working what is not working um rather than just going by our

3:35:51gut feel and the eye test it is the basketball version of money ball which is associated with um billy bean and the oakland a's in fact uh sam hankie's boss with the houston rockets was daryl morey and sometimes um the basketball version of money ball is called morey ball because daryl morey pioneered it and daryl morey uh as you know was a mindscape guest uh a little while ago he later became sam hankie's uh not quite successor but successor of successor as leader of the philadelphia 76ers and

3:36:25a few months ago he was fired sorry to hear that but the reason i'm bringing this up is because it has been quite a journey so hankie looked at the at that time roster of the 76ers and realized there was just no way with the assets they had that they could build a championship contender and in his mind the job was to win championships not to like be pretty decent year after year but to actually win the nba title and they were good enough but not good enough they're good enough to win some games not good enough to win the championship what are you going to do well in order to win the championship

3:36:59you need superstar players how do you get superstar players you can try to trade for them and whatever but if you don't have any superstars how can you trade for them you can try to hire uh attract them as free agents but unless you're a good threat to win the championship that's hard to do so the other way to do it is to draft uh get them through the nba draft which means you need a high draft pick and in the nba high draft picks go to the teams that do badly so the way to success is to get rid of all your good players be bad for a couple of years and then get a lot of good draft picks hit

3:37:34on the super on the lottery and get some superstars and then win some championships now um this generated a huge amount of controversy hinky was basically forced out there's just so much detail here hinky was basically forced out by the nba leadership because they thought that he was losing too many games and making the sixers look bad um his successor brian colangelo was a nepo baby hire he was the son of jerry colangelo who was a big name in nba circles and he had to resign brian colangelo he had to resign in a

3:38:09scandal where he was using burner accounts on twitter to criticize his own players and his wife was also doing that and the whole thing was just horrible and messy and meanwhile the sixers did become good because they were able to draft some good players um they also had some huge mistakes in the draft um that's okay like hinky himself never thought that well once you get a good draft pick you're you're set you want to give yourself as many bites at the apple as you can um and the one big success they

3:38:43had was joel embid um who has been an amazing player won the mvp of the league won multiple scoring titles um but has also had a lot of injury history so he's about i think he's going to be either 32 or 33 years old in this upcoming season so that's that's the beginning of your decline typically as an nba player but you know still in your prime but beginning the the decline downward uh so he's been around for a while but it has been a hilarious series of misadventures with the sixers um they had

3:39:19a draft choice which was like a local hero michael bridges who played at villanova right outside philadelphia whose mom worked for the 76ers everyone was so happy about this uh michael now plays for the the new york knicks just won the championship and they immediately traded him away for another player who then um had a peanut allergy and he ate something that had peanuts in it unbeknownst to him and became debilitated by this and never played nba basketball again like how do you predict these kinds

3:39:50of things um they picked markel faults as a first round as a very first choice who's clearly the best basketball player to be picked that year they put a lot of effort into picking him and as soon as he arrived in the nba he could no longer shoot the basketball and it's sort of an open secret that he clearly was injured he got into some automobile accident and injured his shoulder it's clearly a physical uh ailment that prevents him from being shoot shooting anymore and you know what can you do like how can you predict things like that anyway here we are in the current era and last year

3:40:26was daryl morey's last year and he had made a big gamble he had like gone through a whole bunch of drama with ben simmons and james harden or whatever and he had finally convinced paul george was a very very good basketball player and was the leading free agent on the market in a certain year where they had money to come join the 76ers it was a great coup everyone was very happy about it um but the thing is that paul george um and joelle and bead uh combined uh had a lot of money they're senior basketball

3:40:59players george is like 36 now and imbeed is now was 32 last year 33 this year i think don't quote me on those numbers but they both were injured all the time um for different reasons and the team never quite got off the ground now last year the other two important players they had were tyrese maxey who they completely lucked into you know the thing about luck is sometimes it goes your way sometimes it doesn't so completely true daryl morey was able to draft tyrese maxey relatively late in the draft and

3:41:31other players didn't pick him other teams didn't pick him in part because that was in 2020 the covid year and the ncaa march madness basketball tournament was canceled so a lot of teams didn't do their good scouting and missed on tyrese maxey and the sixers got him and he's blossomed into a an all nba superstars which is great and then the previous year um they had so many injuries with imbeed and paul george and everybody else uh that they really just bottomed out again and got lucky in the lottery and got a high

3:42:07draft pick they rolled a pick third and they picked vj edgecomb who has turned out to be an amazingly good player someone who easily could have been the very first pick in a different year but there were two even more promising players chosen ahead of him perfectly fair they were they're also superstars but basically so the sixers had four really really good players um two of whom had trouble staying on the court and then just because everything weird happens to the sixers paul george uh was suspended for

3:42:3725 games for violating the league's drug policy we don't know what drug it was we're not sure exactly uh what that was all about but you know it just throws another spanner into the works as it were so they entered the playoffs and here's the thing and i'm going to talk a little bit more about this but you have to address the elephant in the room which is joel and bead is injured a lot he is when he is playing at his peak he is honestly as good a basketball player as i as i have ever seen he won

3:43:09the mvp i think three years ago and the year after he won the mvp he was playing even better it was just miraculous thing to see he had a 70 point game he would often score 50 points before the fourth quarter and they would sit him down because they were winning by too much and then he suffered a horrific injury where another player from another team landed on his knee and twisted it in a terrible way and since then he's never been quite the same okay so um but it's there's a reputation that and bead has um

3:43:42acquired of just always being injured never being available and you can see if you don't follow the sixers closely and instead just look from outside at the numbers it's absolutely true that joel and bead has missed a tremendous amount of time by being injured but there's being injured and being injured there's sort of a kind of being injured where you're injury prone in the sense that there's a part of your body that is just liable to give out and there's the also the possibility that you're

3:44:13just kind of unlucky and i will defend the claim that joel and bead has just been unlucky he missed the whole first two years of his nba career because he hurt his ankle he broke his ankle and the the original fix was screwed up it was bad surgery so he ended up missing not just one year but two years but his ankles since then have been fine um the most recent thing that has really slowed him down was the knee which is a whole different part of your body and it was clearly someone fell on it we all know

3:44:45why it happened and that first year after he hurt his knee again it wasn't well fixed but he got a second surgery um that really did fix it and you know the his own claim and the team's claim and the evidence on the court is that his knee is fine now but meanwhile in other years it's just been a comedy of errors one year he ran into his face ran into the shoulder of one of his own teammates and broke his face like literally broke the bone in his face and he had to wear a mask and it was just

3:45:18not the same um another year he had bell's palsy which means that like there was his the left side of his face was drooping and he could only see out of one eye and these always happen just before the playoffs start okay this year he had appendicitis just before the playoffs started he had an appendectomy he had surgery two weeks before the playoffs start he was expected to miss all the playoffs he heroically came back and he led the sixers to a thrilling come from behind um victory in the first round of

3:45:51the playoffs where he was clearly the best player so on the one hand yes joel and beat has undoubtedly been injured an enormous amount and if all that is what you knew you would be smart to play the odds and say he'll be injured again on the other hand they're all weird injuries they're like there's there's something called the gambler's fallacy where you say well i've been having bad luck for a while therefore i am due to have good luck that is a fallacy that is not true but it's also a fallacy to say i've had bad luck again and again and again therefore i will just keep having bad luck okay um

3:46:27i would argue that it would not surprise me at all for joel and beat to be perfectly healthy this year in fact at the beginning of last year before they started playing the games and beat said very explicitly i'm going to be back this year but i won't be 100 healthy until next year and he was right and this is the year where he predicted he will be 100 healthy so that's all preliminary to saying that um last year it didn't quite work like they they got to the playoffs uh actually they

3:46:57didn't get to the playoffs they got to what is called the play in where four teams uh play for two slots but they won their play in game and they faced off against the hated boston celtics and they went down 3-1 and imbeed sort of worked himself back into shape after the appendectomy and um willed them to a thrilling 4-3 victory after being down 3-1 the only time in the history of the boston celtics franchise that they have lost a series after being up three games to one but you know honestly it was

3:47:30pretty clear that all of that heroism to win the series after being down 3-1 left them completely wiped out and then they hit the new york knicks in the second round and walked into a buzzsaw and got destroyed uh four games to nothing and it didn't help that nick nurse their kurt their coach um really played all of their players very very heavy minutes so that like you literally saw because i was watching these games they were competitive in the first three quarters and then they would get destroyed in the fourth quarter because they were just too tired so okay that's fine so that's where we are

3:48:04at the beginning at the end of this season and both paul george's contract and joel and bead's contracts are so big that even though they're all-star their first ballot hall of famers once they retire um they're considered that no one would ever take these contracts on because they're they're not able to play enough games so um the sixers fired daryl morey i feel bad about that but they hired this guy mike gansey who gotta give credit has been working miracles the first miracle he worked was he traded

3:48:37paul george to the boston celtics for jalen brown jalen brown is another all nba level player uh he's younger i think he's going to hit 30 this year again i'm not so clear on the ages um he has his own issues uh which we can talk about but clearly at a basketball level by itself is a clear upgrade to paul george and they had to send in a couple of um extra draft picks to do it but everyone in

3:49:08basketball land thought that the sixers got the better end of that deal and because of that there was one domino waiting to fall which is that lebron james who is you know among the top basketball players ever to pick up a basketball well let's just say that arguably the number one best basketball player of all time um reaching the end of his career he's uh he's showing us superhuman levels of longevity in addition to being an amazingly good basketball player in his prime he's been able to keep

3:49:39up his super high level play very very long he's going to be 42 this upcoming year um there's never been an nba all-star level player at age 41 or 42 but he was absolutely playing you know not at a top five player in the nba level but at a top 20 player no doubt last year um but he was in los angeles and they had uh pulled off an amazing trade for a much younger superstar luka donchik donchich and uh it

3:50:10was clear that lebron was no longer in their plans and so he basically in some sense he said you can't fire me i quit and lebron said i'm leaving and he also said you know he's like the wealthiest nba player ever he has a lot of money because he's been doing well for a long time he says i don't care how much money i make i just want to go to a good situation people thought that lebron might want to go back to either cleveland or miami where he had previously played or maybe to golden state to join his buddies steph curry and dameron green to have like a last hurrah but instead to certain people's

3:50:42shock he joined the philadelphia 76ers now there's a lot to say about this a lot a lot to say about this but the short version is uh we are all over the moon here in philadelphia 76ers fandom and i'm certainly over the moon too because not only is he lebron james one of the best people ever to play basketball but his skill set is exactly what the sixers needed and it's very funny for me to see people who are professional basketball commentators who clearly haven't watched a lot of sixers games

3:51:15because they're saying a lot of stupid stuff about how lebron is going to be yet another superstar who needs the ball all the time and that's going to hurt the development of other players on the sixers and whatever it's just completely backwards at this stage of lebron james's career the thing he most brings to the table is his super high basketball iq and his ability to both literally pass the ball but also just more generally orchestrate the offense and the defense uh in real time which is exactly what

3:51:46the sixers were lacking tyrese maxey who is an amazing player and love him to death also just one of the most likable players in the nba has been the sixers point guard he's been the one delivering the ball the passes as well as scoring himself and so people have this idea that he needs the ball to be successful but any sixers fan will tell you that when he is at his best is when someone else is the point guard and he gets to catch the ball and shoot and make uh um what we call attacking closeouts where you catch

3:52:21the ball someone runs at you and tyrese maxey is literally in the in the conversation for the fastest player in the nba so if he does get the ball to shoot and someone tries to close out on him very quickly he can move past them and get a layup like nobody's business lebron james is exactly the person you want to have playing that role and his best position these days lebron's is uh power forward which is exactly the one position that the sixers did not have a great player at they have

3:52:54very good players but they're backup level players and so lebron fits in to this scheme perfectly um the other guy vj edgecombe uh who's a rookie last year was uh a super talented rookie and he's going to get better this year so basically you have four players in the starting five who are established all-stars at least two of them uh mbead and lebron are easy first ballot hall of famers and the other

3:53:24two jalen brown and tyrese maxey are likely hall of famers and then vj edgecombe is going to be in a second year of a promising young career it is arguably the best starting five ever to take the court in the nba now that means nothing that means nothing as far as results are concerned uh i think that there's all sorts of reasons to think it will work and i like i said in the intro i choose to be an optimist and a fan and think that everything is going to go great at least until it doesn't now

3:53:58i'm also not completely irrational and i can be a realist when i want to so there are some things that could go wrong i think that there are three things that could go wrong that are reasonable things to worry about um and i will list them and what i consider to be increasing order of concern one is mbead's health i think mbead is healthy and i think that he's going to surprise a lot of people um but you know the numbers don't lie he has managed to find weird bizarre ways to get injured many times in the few in the past so it could happen again that's absolutely something to worry about and

3:54:33especially because we don't have great backup centers that's the one position when it comes to the bench where the sixers are not very well stocked right now so it's a it's but what can you do about that i think that that's just something we'll have to roll with and see how it is the second thing is lebron james is going to be 42 years old it's unheard of literally unheard of for someone to play high level basketball in the nba at that age people have played a couple a handful of people but they're they were clearly you know benchwarmers and whatever um we're relying a lot on a 42 year old

3:55:07guy to keep it together and play at a high level he's been declining but the decline has been so gradual it's been weird um it's absolutely possible that this year will be different and he'll have more serious decline i think that there's reasons to believe he'll be energized by the new situation by the new challenge by the new prospect of winning an nba championship with a fourth team he's won championships in miami and cleveland and la already so i'm optimistic that lebron will um

3:55:39step up to the plate here but it you know realistically being 42 years old things could happen you don't you don't wake up quite as bouncy as you used to i can i can vouch for that the big question for me is jalen brown so jalen brown um is a hugely talented basketball player but he's a very kind of specific basketball player and he's not actually an obvious perfect fit with the rest of the operation his talents are like last year his running mate as it were his fellow superstar on the celtics

3:56:12jason tatum was injured most of the year and jalen got to sort of be the alpha dog and he was very good at that the celtics won far more games than anyone predicted led by jalen brown and part of the reason why he was willing to be let go by the celtics is because he wanted to be the leader of a team all by himself rather than playing second fiddle arguably now he's playing fourth fiddle so that's not the direction in which he wanted to move and the specifics of his game are very much about him

3:56:44having the ball and being the alpha dog and having an isolation call for him and working his magic and so there's good parts and bad parts to that the good part is sometimes you just need someone to step up and get a bucket all by themselves with individual heroism and he is the perfect person to do that the other downside is often when all the other players on your team are world-class good you need to be a little bit more part of a system not just an individual hero he's not especially great at shooting from

3:57:16long distance three pointers um and you know in a very real way a younger paul george is a better fit to this team than jalen brown is right now um but two things about that one is that paul um paul george is not young anymore and number two i could see by watching last year i could see why paul george rubs people the wrong way a little bit i mean he's incredibly talented he has the ability to step up and just control a game for brief stretches but he doesn't he kind of blends in and you know when

3:57:54he he he shoots and scores in sort of low impact moments more often than in high impact moments whereas jalen brown is both younger and bouncier and is pretty good at rising to the occasion but what i can see the the possible problem is um jalen not wanting to fit in if jalen brown decides that he wants to do what it takes to win an nba championship and really dedicate himself to playing defense and to sharing the ball and playing smart high iq basketball with these other

3:58:29super talented teammates the sixers will be unbeatable next year i mean if he chooses to do that there's just no one that can stand in their way but he might not you know and i don't know i truly don't know that's a completely valid concern in my mind to be fair um we have three players now who are a little bit of drama queens between joelle and bead lebron james and jalen brown none of these people take it quietly when things are not going their way and i think they're all good people i think

3:59:04they're you know their hearts are in the right place but um they're not like the tyrese maxis of the world so tyrese can just play with anyone and and be a success and everyone loves him and uh these three are more prickly pears a little bit i think that winning solves a lot of problems and if they find themselves winning a huge number of games everyone will be happy uh but that is something that i would at least worry a little bit about otherwise i'm not worried about a lot of what people are worried about they're worried like oh there's only one ball that's fine the ball will be

3:59:35in the hand of lebron james one of the best players to ever play the game and think of it this way if you're the other team when you're when you're playing five on five basketball the first thing you do as the coach of a team on defense is say okay um some of our players are better at defense than other players we every team has some people who are not good defenders we're going to put our worst defender on the other team's worst scorer right that's a very natural thing to do the new philadelphia

4:00:0676ers have no bad offensive players there's nowhere to hide a weak defensive player the obvious choice is on vj edgecomb the guy who was the rookie last year who in his very first nba game scored 34 points he scored far fewer than that on average because he specifically deferred to his older more established um teammates not because he couldn't he's an amazing scorer from all the different parts of the basketball court so good luck with that there's other people so basically lebron james is going to

4:00:43start the offense he's going to push it around and choose your poison you can have joelle and bead uh in the post or at the nail and you can have um jalen brown and vj edgecomb and tyrese maxi zipping around the perimeter uh making screens for each other you can't double team anybody because you can't leave anybody open on this team good luck stopping them from scoring you might worry about the defensive side but again i think this is something where people don't watch the sixers and that's why they

4:01:15had these opinions um i think that joelle and bead and lebron james both have the property that they can be super good defenders when they want to be now admittedly these days they don't usually put their energy into that they put their energy elsewhere but guess what on this team they can put their energy into that because there's so many players that can score the basketball so if they really you know they might coast a little bit through the regular season but when the playoffs come out and they

4:01:47really need to shut people down both lebron and joelle can absolutely do that tyrese maxi is a little tiny guy he's like my height okay um and that is a disadvantage but he's super dedicated to the defensive end and if you look at the numbers he's an absolutely average nba defender jalen brown like i said as all the tools to be a well above average nba defender sometimes he does that sometimes he doesn't bj edgecomb is an elite nba defender already as a rookie if you look at the numbers he's been

4:02:20tasked with guarding the other team's best players and has done an incredibly good job so i'm not even worried about the defensive end um i am very excited about the upcoming season i think that that the sixers and the city of philadelphia and their fans deserve something to go right for them after all the trauma of the last decade or so um no way of knowing whether it's going to happen or not if we knew it would be less exciting it's living through the experience that is worth it

4:02:52i can tell you that i'm going to be going to some sixers games this year if i can afford them who knows they might be out of my price range these days um but i'm very excited to see what happens i love the team both as it's constructed and the individual members of it and um i'm going to try my best not to devote too much ama time in the upcoming year to talking about the philadelphia 76ers but if they win the championship i'm not gonna be held to that promise so thank you all for listening to this

4:03:24month's ama thank you all for supporting mindscape thanks especially to the patreon supporters for doing more than just moral support uh hope you enjoyed this one i'll talk to you next time

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