[Music] hi i'm lawrence krauss and welcome to the origins podcast this episode is with a fascinating individual stephen wolfram who's had many different careers stephen began as a young scientist a very young scientist self-educated basically did without many degrees and went on to do a phd at caltech after educating himself and i think got it when he was 21 and was working with richard feynman then he went on to continue to do physics and went to the institute for advanced study among other places but decided to branch out he's always been kind of an iconoclastic individual and decided that what the world needed was a new way of doing mathematics on computers and he created what was one of the first symbolic manipulation programs something it allowed you to do not just number crunch with computers but actually do symbolic manipulation do algebra and mathematica the program he created the company he leads became really the prime way that most scientists most physicists at least now do complex algebra they use mathematically to do it as well as much more but stephen didn't rest on his laurels of just doing mathematica during that time he's always been interested in doing research and following up on ideas of something called cellular automata to think about new ways of trying to understand fundamental physics and he's made great claims about what he what his new way of doing science as he talks about it might do for understanding physics claims in fact that he can really reproduce all of fundamental physics with his symbolic manipulation and these cellular automata ideas and i wanted to talk to him about that and we did we talked about that we talked about his early history in physics we talked about many things including how important it is to know how to type and it was a fascinating conversation that i hope you'll enjoy if you are watching this on youtube i hope you'll consider subscribing to us on on youtube because it'll help us but it'll also help you because 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some of your work but but we'll get to that but it's been at least a decade but we go back we go back i was trying to think we go back 40 years actually probably yeah yeah and uh yeah well you were we were both in the particle physics business yeah we were both in the particle physics business i'll uh you know i'll go back there but i want to go back even further as we as we delve since it's the origins podcast i wanted to um uh i wanted to begin with your origins and uh which are interesting and i learned a little bit more i knew i knew some things about you already but uh but in the in the lore of steve stephen wolfe from i've learned some more maybe some of it's true um one thing that's interested me uh so uh your parents were i was trying to i always like to figure out where people might have gotten their interest in science or things um your mother was a a a philosophy fellow at at oxford right yeah does she have to translate into american it would be philosophy professor yeah yeah they didn't call them that they call them philosophy yeah absolutely so did she did she have an answer she had a phd in philosophy did she have a phd a phd was an anthropology because they didn't actually do philosophy phds back in those days philosophy was thought to be a field in which you couldn't get to be a doctor of philosophy ironically enough yeah that's right was probably a good idea actually um yeah that's probably a very good idea so she so it was anthropology i wonder first whether her interest in philosophy might have been formal logic and that end of philosophy but perhaps not so she wrote she wrote actually a reasonably well-known textbook on philosophical logic which is different from formal logic so she was not a mathematically oriented person she was more of a uh kind of linguistic philosophy kind of person and she worked a bunch on on those kinds of things and and uh she i mean uh no my my interest in science came from being orthogonal to what my parents did actually two things that came from it came from being orthogonal to my parents and it came from the space program which was kind of the big thing in the 1960s when i was growing up was kind of you know i was young i was interested in the future the future seemed like it was things like the space program sure so that's that's uh you know got me interested i mean having a philosophy professor as a mother has interesting features like you know it's like you explained something not that she knew much about science but i would explain something to particularly to friends of philosophy friends of hers and they always say well how can you know that oh grand i actually there was a i remember a philosopher of time that i remember when i was a young lad um probably i don't know 10 11 years old you know and i was having i remember this this big argument was a woman who was a a quite well-known philosopher of time as it turned out and it was like you know look i understand relativity this is how things have to work et cetera et cetera and um yeah that that uh and she was like so one of the things that came up there was was i'm like okay there's this you know time dilation all that kind of thing and she's like how do you know that a human you know a biological thing is going to actually show time dilation it's like okay you can figure it out for a clock etc etc etc and i was like but it just has to work that way i didn't really quite know why um now i think i do finally know why but that's that's 50 years later or something it's some but i was i was kind of and then later on when i was like thinking about that and i was learning about gps satellites and things i was thinking gosh we finally have a way to actually see time dilation let's use the gps satellites yeah whoops they back correct for time dilation that's the whole point yeah if they didn't we wouldn't be able to get to the nearest theater or anything else yeah yeah right it's kind of amazing that they don't obey you know time dilation they they are you know and the question is the rat or the human going in the spaceship why should they any more obey time dilation than the gps satellite so that was a that's an example of my uh my kind of um uh i felt a bit silly you know 40 years after that conversation realizing that the insistent young you know science oriented 10 or 11 year old was like no no that's how it has to work and actually it's a little bit more subtle yeah well it is you know it's funny when you talked about a philosopher time which i is an amazing concept but then occurred to me in some sense at least reading some of your recent stuff that's kind of sort of what you become in a way at least part of what you've become is a philosophy yeah right i'm learning a bit more about what time actually is and we'll get to that eventually uh and you'll explain to me because i because yeah i have a con i haven't think i understand having read your stuff but i'm sure i could be that understanding could be improved upon but it was nice that you had those discussions but it is interesting that so she was more linguistic and your father you said became a novelist he neither of them as you say were mathematical at all my father was was i mean mostly a businessman yeah and um wrote novels as a kind of a hobby and uh that was um you know they were look i i was uh a first child i have a younger brother who's ten years younger than me but i was effectively an only child and and uh and probably a strange child at best i i suspect but uh but the fact that if you really had those conversations that at age 11 if it was really those i mean that's kind of a useful thing because asking if they ask you questions how do you know that that kind of promotes at least the kind of scientific thinking i mean how operationally yeah yeah right that i would always say at the time it's like look philosophy is just crazy you know how can you guys have been debating the same questions for 2 000 years yeah this is just a stupid field i know i have great science we make progress yeah well that's what i've said in the past and i've gotten a lot of hate mail for that but uh well i think it's a subtle issue and i think one of the things that's been a big surprise to me actually in recent times is from science that i've done i finally understand a bunch of what philosophers are trying to say often in terms that they didn't have they were they were trying to describe things in terms that were a thousand years after their time so to speak and so what they sound what they say sounds kind of goofy to us today but as you actually understand what really seems to be true scientifically it starts to seem a bit less goofy but you know i i'm i'm kind of one of my early memories or something from from sort of the what will you do when you're grown up type question i probably was about five or something i was at some some party with a bunch of adults with with uh and you know i i was probably one kid at the party and there was a bunch of philosophers and um uh you know some old white head philosopher comes over to me as as i would do probably in the in the current time and and says you know the kids probably more interesting to talk to than a bunch of these middle-aged adults yeah sure so i have this long conversation with this guy i forget about what and then he's walking away and he kind of mumbles to himself i can hear him sort of mumbling you know one day that child will be a philosopher it may take a while i suppose that was a compliment that's very good i suppose yes 50 years later or something it's so more um it's maybe that's right well um by the way did you were you're you're five years younger than me i think so you would have been a little young for the apollo landings but but i watched those yeah from school oh you too i stayed up all night long i had a little command center downstairs in the basement and okay well for me it was like two in the morning i think the the uh the the setting put on the moon was two in the morning british time yeah yes i i did watch that in fact i i i used to keep very close track of that you know i i was a always a producer of lots of written material so i still have all of the um uh all the kind of notes that i took about the precise things that happened in all those spacecraft which was i don't quite know why i was so into it but it was it was kind of a well it was a kind of this is something about the future no thank goodness yeah right well it was but it was it was kind of it was thank goodness i didn't sort of stay concentrated on space because then it would have been hibernated for 50 years until people actually started taking it seriously again but um no i mean i you know that was i i started kind of um oh i i guess i got interested around probably age 11 or so in 10 11 something like that i've been sort of in this i'm going to design spacecraft not clear what that meant and so then it was like then i have to learn physics i guess and then i got really interested in physics and i started doing things like i i have this artifact that somewhere on the web from when i was like 12 of this kind of uh sort of concise directory of physics which is all these sort of things i looked at your little scrapbook i've been going through it today you know it's amazing well what's what's kind of funny about that to me as an observer of the human condition is you know you look at that it's a bunch of facts about physics and tables of data and things like that and it's like and then i look at wolf from alpha and it's like oh my gosh i've been doing the same thing all my life it's kind of uh and actually when i kind of re resurfaced that thing from when i was 12 sort of one of my first instincts was take some of those numbers type them into waltham alpha see see what was right yeah i know it their connection was not lost on me in fact it's it's been fascinating for me to look back at some of that knowing you as i do and see and see some of that i didn't i'm not surprised but i didn't realize that you were so pristine prodigious a note taker and recorder of things i i the only person i know does that with my friend alan guth basically at the every night more or less records everything that's happened during the day and okay and i didn't know that about him okay yeah yeah well when i i mean i don't i assume he still does when we worked together it was always that way and it was uh remarkable and sometimes frustrating because he'd often be behind because he was trying to keep track of every single thing and it's you know when most of what i keep track of you you know i've i've recorded probably more sort of personal analytics stay true on myself than i think anybody else i was shocked about as passionate all of it is past i mean i i if i had to lift a finger to do it i mean i lift my fingers and tight keystrokes but they're just passively recorded okay um it's not um uh you know if i actively did it forget it not gonna happen yeah then you would lose by the way what's the what's the log just in case people wondered you apparently you've recorded how many keystrokes you've typed in your entire life yeah and i don't know if you haven't quite entire life but but almost but did you have a little thing on the upper left-hand corner of your screen or anything what's that don't ready for that actually it's an interesting idea i don't have that i it's um i have uh every day i do know how many key strokes i've typed each day so for example i think i think yesterday i i yesterday was a 50 000 keystroke day so that was okay that was a that was a decent day is that an average day for you fifty thousand no it's it's actually higher than average i was i was writing some stuff and um you you do write in in you do write you when you write it's never a sound bite let me put it that way well i know i know i know i you know i wish i could write shorter it was uh you know when i was working on my new kind of science book for a decade that book is is in a sense even though it's a big book 1200 pages long it is sort of a minimal length book in the sense that every page it's kind of compressed as much as i can compress it i kind of decided that wasn't the right optimization and i didn't want to spend another you know 10 years writing things so now when i write stuff i write you know at sort of output i i write it as i think about it and i write whatever i'm going to write and you know i could probably compress it by a factor of four or something but i figure it's better to write it more at more lengths there's probably more stuff in there anyway and then i'm actually going to get it done rather than saying well one year i'll get it done and never get yeah it takes you know as everyone knows it takes a lot more time to write something shorter as you know there's that famous letter if i'd had more time this letter be shorter yeah i forget one of the british someone famous said that and i'm no doubt someone will let me know who said it so so it was it was i was trying to think where the interest in physics came in but there but there was an early interest in math now there's this you know you you said somewhere oh i wasn't very good in arithmetic i actually looked at your grades there in one of your things they weren't too bad actually i mean it was said you know you had trouble with your times tables or something like that which now of course can be done passively too because mathematica i'll give you that but but um um but but there what turned you on to mathematics then was it the was it that i needed nothing because i i was you know i was interested in physics mathematics was sort of a necessary evil for doing physics yeah exactly i was wondering what you needed to do physics so you learned it basically right i mean you know and i i actually didn't like learning it and that's why i got computers to do it for me and that's that's kind of the uh um but but subsequently what what has happened is that i got interested in kind of what is the essence of things what is the sort of ultimate abstractions of things and from that i've gotten very deeply pulled into sort of advanced areas of mathematics and kind of uh abstraction and mathematics and so on in fact one of my one of my current projects is finally to understand what mathematics is we can maybe come to that um okay but um put that at the end but i think the um no i i mean for me i was never you know i i think it the the way one gets taught mathematics and you know in school and so on at least in in british schools of the time it was uh an awful lot of math trickery which i was never really into it's like there's this particular integral and you can you can do this particular one because there's this cool trick for doing it yeah and you know what i learned at some point in like doing integrals because i wanted to do them for physics was these big industrial machines like you turn an integral into a product of uh well nowadays it would be mere g functions but then it was like poly logarithms and other such things all these kinds of exotic functions and and you know you you basically make a a completely boring to implement industrial machine that will grind through all these integrals and you know mostly that was that was you know set up to be easy to do on a computer but even even by hand i would do those things and i think you know back in those days well i even did you know i i sort of made it through my sort of first year of physics undergraduate type thing and i think i even came top in the exams which was which was a tribute to the exams more so than to me i would say because it's it's happening by that point i was kind of able to do sort of professional grade physics stuff and the only question was you know if you could get to the answer but using completely alien methods was that okay because i certainly couldn't get to the answer using the you know there's this trick for doing a trig substitution of this and that kind and it just happens to work for this integral not not my kind of thing at all interesting that you say that i'm going to jump ahead i i because i can't resist because your old pal who i i knew as well richard feynman and and you know i i not only knew him i wrote a book about him he was famous for developing tricks to do integrals it was one of the things he he in fact is an essential part of of in some sense that using feynman diagrams to understand to calculate in particle physics in order to use them he had to develop a lot of tricks to do them did you um well yeah i talked to him a bunch about that because when i was working on s p which was kind of for foreigner of mathematical language and so on um he was you know i was talking to him a lot at that time and he kept on telling me you should do this you should use this method you should have and his his tricks were a little bit more general than tricks i mean he had you know definite methods of you know you would take this general thing and differentiate with respect to a parameter and and this that and the other i mean i know you know i i noticed a few years ago i uh one time i was at his house and and he said you know i've got these notes about how to do integrals for finding diagrams and he said you know they were made sometime late 50s i think said they'll be more used to you than to me so it gives them to me and it's like well i give them back sometime i still have them of course of course yeah i mean it's kind of the uh the um but it's it's interesting because that was he was a very in a sense he was a very low-tech mathematician in the sense that those those notes they're really about poly logarithms and things like that and there's all kinds of fancy theory of poly logarithms now that wasn't his thing at all no no it was just using him to get results but also his his approach to mathematics was very much a the the most powerful 19th century mathematics so to speak um he really didn't trust 20th century mathematics interesting but but i think that his um uh no he was some i mean i i was always you know though we tried to do some work together various times we worked on quantum computing actually back in 1981 and and um it was always a an interesting experience because he would do these calculations of you know spin chains and this and that and the other and i'm like i have no idea why that result is correct and he i would do some computer calculation and show it to me he says i have no idea why that result is correct and so it was a it was a little bit um uh challenging to communicate there but but it was no he was i mean the most impressive thing as far as i'm concerned is you know he would go through and he would calculate stuff and he would actually get the right answer yeah yeah which for me without kind of you know i can i can get a computer to get the right answer for me by hand no way i'm going to get lost in some whatever but then you know the thing that was was always a sort of paradox of dick feynman was that you know he would you know he would come up with this this you know calculation then he would say that's not impressive everybody can calculate stuff which isn't true of course yeah and he would say i've got to come up with you know some grand intuitive explanation that's really going to impress people and i remember like with the part on model and field theory and so on i remember you know he told me he'd worked out all this stuff about scalar field theories and how these patterns would work in scale of field theory and he just tells people oh there are these part-ons and they're these point particles and so on and it's all obvious how it works and and people are like why why does it work that way and he never told anybody yeah he worked out this whole theory yeah i mean that's famous about feinman he loved to be appear to do things by magic but then when you you know when you go back and you look at the notes there was you know 30 000 pages of notes he'd done he'd worked it all out and that's to me one of the more amazing things about him he said he and that's why he had this incredible arsenal it looked like he was pulling things out of thin air but they weren't pulled out of thin air they were based on years and years of calculations which which he developed and retained and and and and could use that incredible arsenal to make things appear magical and it was uh yeah when i was writing the book about him it was really interesting to learn those details and but he certainly loved the magic he certainly loved to appear i mean you know there's i i think i it's a famous story about him but you know uh it was one of the things i put at the beginning of the book he just reminded me of it you probably know this story when he's a kid and he would and he would get mike money by fixing radios do you know the story it's just perfect it's a perfect it it was it was dick feynman emerging right then so he would um it was back in the days of tubes before they had you know pen sisters and stuff and so he um or solid state uh circuitry and uh he someone brought this this uh this radio end that was making this uh this awful noise and um and and and he he he was a little kid right and he walked around he walked around he walked around pondered looked after the sky pondered and then and then you know switched two tubes and the noise stopped and and and you know he knew he'd known right as he said he'd known immediately what the problem was but the whole idea was to was to make it appear as if this magical insight came to him and you know he was a showman from the beginning but the difference between him and many showmen is that he had it was more than just show and and he and uh and remarkable but it's interesting to me that that um that you had two very different ways of thinking about at least how to do calculations right you know i think that one thing about about feynman that is he genuinely didn't think it was impressive that he could do these calculations um and you know i know it's something i've slowly learned about some things in my life where it's like that that's easy you know that's not impressive i'm not going to tell people about that that's easy and it turns out you know years later you realize actually you know most people can't do that at all yeah i mean i i just i just realized that actually about something just a few days ago about something that i kind of had always assumed well i never really thought about it i never thought why is this hard and um you know the the issue i can describe it's it's like when you uh you know we're jumping years later but you know studying complexity and things like this making models of things and it's it's always i realize there's this kind of process of meta modeling you know you have a model of something you say what is the underlying essence of what's there in this model and that's something you know when i worked on these simple programs as models of things and so on a lot of what's going on there is you say there's a model which may be a quite accurate detailed model but what's the essence of what's happening there and i i kind of realized i mean that's something that i've sort of naturally been interested in and found but then i realized actually that's the same thing one does in in computational language design is you have to kind of drill down to the essence of things and for me that's just something i naturally truly like to do and end up doing and it's you know and i'm like why do other people not do this well i just spent 40 years doing that kind of thing but it doesn't but to me that's sort of an obvious thing one does and doesn't happen to be so obvious to other people because just hasn't been what the pattern they've taken yes i can but i guess that's one reason why you and i at least were doing particle physics i think early on and and i mean my interest in particle physics i mean it's the sense that physics is reductionist as and and and and fundamental physics is reductionist uh at the level of particle physics the idea is the same thing is that is that you're looking for the essence you're looking for the fundamental laws and that was certainly attractive that's why i that's why i became a particle physicist i want to know what were the essential laws the fundamental laws of of nature the fundamental roles and i suspect we had the same um i had the same same interest i mean what what i've now you know now i'm at a machine code way below particle physics so to speak um but uh you know particle physics was good in its time i mean i i realized actually one strange thing when i was um like 12 years old i was learning for physics and i had this um this series of books the berkeley physics course books and the volume five is about statistical mechanics and on the cover it has this series of frames of kind of collisions of you know idealized billiard ball type collisions it's kind of supposed to be illustrating the second law of thermodynamics the you know law of entropy increase and so on and so on and so on so for whatever reason i was really interested in those pictures and in how second law of thermodynamics works and that book i i can't quote it after all these years but it's one of these books where it says you know here's the derivation then it says oh by the way we can run this derivation in reverse time this point is often puzzling to the students that's kind of like uh but but um you know my some of my earliest sort of computer simulations were an effort to reproduce those pictures i later many many years later i talked to people who made those pictures those pictures were a fake but it didn't matter to me well they were you know the berkeley series it's interesting that it got you that they had the pictures those were an amazing series of physics chicks they didn't they weren't always successful in teaching because they tend to be too hard for most students but they're fantastic my favorite is still probably ed purcell's which is on electricity magnetism which is right i remember that one orange cover as i recall yesterday i think so yes and it uh he was an amazing i worked when i was at harvard he was there and and he every time he was one of those guys where every time i talked to him i wanted to grow up and be a physicist even though i was right right yeah but you know what's funny is that that in a sense second law of thermodynamics and you know what how do you get sort of continuum behavior how do you get uh randomness from from these kinds of things that to you know i i started with that i then got interested in particle physics because particle physics was kind of a happening area in 1973 and several yeah and and then years later i kind of got back i was going to say i was going to say you're right back to in some sense there's a lot of there's a the it's when i read your stuff now about about your what you're trying to work on it's very reminiscent of statistical mechanics of the arguments of macrostates and microstates and yes and and uh and i i was struck by that and and you and to some extent you even say that in in at least one of the pieces i read by you and that that that um that there can be many you know as and i'm again i'm jumping way ahead but just as the particles in this room could be in many different micro configurations but they're still the same temperature and pressure and if all i'm measuring is the temperature and pressure i don't worry about all those configurations and in some sense if i get what you're saying that we who are quote computationally bounded and we'll get to that can't experience all of the different things that are going on and we interpret the fact that we we can't we can't that it's that we it's computationally irreducible that you can't follow all the particles and that we sort of summarize things ends up being our our view of time anyway we'll get to that so but the arguments are you know i was trying to trying to digest things and and and trying to get to the gist of what you were going to but we're jumping way ahead but that's okay right back to origins okay let's take actions so we you know particle physics so we had the both the same interesting part i was going to ask why particle physics but i think we've already answered it your interest in particle physics the same as mine it's the fundamental essence the difference was i should say that you knew what particle physics was when you were 11 12 or 13 and i certainly i was probably 16 but well i was older before i really knew what particle physics was i i had no i knew i was interested in fundamental things but i didn't know what the fundamental things were and i was and and and to give you credit i i did look you know because i was skeptical at the books you wrote on on on various aspects of particle physics when you were 13 and 14. and unless i mean the skeptical one of me might say well maybe you were just copying things from some text but it looked to me like you actually understood it and and and i and it's very impressive stephen i was it you know they they're understanding the weak interactions and and in fact quantum field theory and i was going to ask how did you learn it now before i get there i wanted to say it seemed to me that you weren't good at arithmic arithmetic times tables but calculus which is the essential tool that you kind of need for physics i mean arithmetic is useful too but um was something that you grasp onto early if i'm reading you know reading this stuff and so how did you learn what led you to learn calculus and then quantum field theory let me ask that well so i mean the first thing was the first meta discovery i suppose age i don't know 10 11 something like that was you can just learn stuff by reading books that's a that's a you know that's an important meta discovery yeah you know i i went to very good schools and you know i learned uh i suppose the things uh it's sort of interesting that you know at the time i was learning you know latin and greek and god knows what else and i was like this is always going to be useless to me and now you know right behind my desk i've got you know latin dictionary greek dictionary and i'm always trying to make up words for things and so on but uh you know i i was but what i learned in school kind of rapidly diverged from what i was interested in learning uh and sort of my my kind of uh hobbyist physics activities so to speak and you know i just i just read books and i i suppose one of the things was that i never did exercises in any book i mean these books had exercises i never did them it was always like well i just wonder about this question and can i address this question can i understand the answer to this question and it was kind of like well you know let me learn this piece and that piece and the other piece and i'm sure you know for years there were lots of places where i'd learned physics and other things where there were holes i just never cared about that thing and so that was a you know in in many you know many many years later there would be situations where i would like realize i just don't know anything about that and because you know and if i'd gone through standard kind of schooling that would have been you know i would have necessarily done a class about that particular thing but um it was a very efficient way to kind of get to the frontiers if you say this is the frontier i want to get to and then you learn all the pieces to get to that front and just the necessary pieces and just the necessary it's not all the pieces but the necessary that's right that's right i mean and and then you know and gradually it sort of fills out and and you kind of make use of things but but i think in um no actually i was recently reading my description of quantum fields from from when i don't know when i was 13 or something actually wasn't terrible it's actually not something i i looked at it wasn't bad at all i was i was impressed because i was i was proud of myself yeah yeah i was skeptical steven i mean i know you and i you know i appreciate you but i still figured out well you know i'd heard what you know these different things you've done when you're younger and i thought okay well there's a lot of young kids who think they've done something good but they were really they're really good descriptions but you said something though that that i'm sure i don't well what i don't think it came out the way he meant it so we'll see you didn't do the exercises but again quoting fieman who once said he who can do nothing knows nothing you may not have done the exercise in the book but you can't learn the physics passively you can't just read the textbook and not at least work some things out because only when you work it out so it may not have been the exercises in the book but you had to work out things in order to figure out how to do stuff i was terrible at reading the books as well all i was doing was this is a thing i want to figure out okay now let me try and figure this out i'll read the parts of the book i need to figure that out and then you'll do that you'll do the work the yeah right when you do the math right right right i mean you know so what happened is like 1974 was when the jape site particle was discovered and it was when you know a plus c minus an annihilation cross section was going up and all these kinds of uh things that in those days i thought were exciting um and uh you know and and so i started trying to figure out you know could i have some theory about this and eventually i came up with this theory about strongly interacting electrons i realized i read that paper by the way i just thought it was but not for but for a young person for a 14 year old it wasn't quite so late but yeah it's some on a grand scale it was kind of lame although you know as i as i noticed recently there i was talking about you know maybe electrons have a size of 10 to the minus 18 meters now i'm saying maybe electron subs are supplies of 10 to the minus 81 meters so it's kind of like um it's again nothing nothing nothing really changes but the details yeah you know no i think you know in in it was the process of writing that paper was kind of interesting because it was like you know i i've seen a bunch of these papers i'd read a bunch of papers in physics journals you know i used to bicycle to the local university library and go look up physics papers um and screen that you could do that right well it was um uh you know in those days random you know 13 year old or something showing up at a university library nobody you know there was no kind of grand security or anything i don't think anybody um but i think that um in uh you know that was so you know i read a bunch of these things and i thought well i've got some interesting things to say when i try writing something about it and i had no you know idea about you know the academic system and the whole whatever and it's just like you look at the journal you can see you know i can plainly see this is the redress you send it to off you send it and uh you know steadily it gets you know you get that stupid referee reports and then you kind of which might have caused me to just say forget it i give up but it was like no you know what you know this is just dumb i'm gonna i'm gonna keep pushing forward so to speak um so so that was a uh um and my papers steadily got better i would say did you did you follow did you in writing the papers i mean again because i've had a lot of students and you have to sort of train people how to write scientific papers but again one way to do it is look at the scientific papers and try and mimic the style at least to you know so you don't write something that sounds like a high school composition or you realize that in a scientific paper you don't put everything you know uh you just and so you did you mimic the style that you of the papers you read a little bit i mean you know one of the things i you know i guess i was always you know in school writing was one of my sort of one of the things i didn't do badly and i was yeah your early grades were very good i know i got right it's some um you know and i i so i mean what was interesting about scientific paper is a very different style from writing other kinds of things sure sure but but i you know once i got kind of the basic idea it wasn't wasn't so hard to do that i mean actually i remember one paper i wrote must have been when i was 18 or some 17 or so was about cosmology and particle physics okay and you say you don't put everything you know well i i gave a pretty good summary of cosmology and particle physics the big version of that paper was never published yeah sure because the journal said oh oh this is all well known blah blah blah actually it wasn't well known at all it was a pretty clean description of how you know how things work with particles in the early universe and so on and i published a shorter version of that paper that was um uh you know that was much less interesting really than the full version because the full version also had had a bunch of things about kind of the intuition behind expanding universes and and uh you know particle interactions and so on which which was gone in the small paper so it was a it was a a piece of uh you know one of those pieces of academic feedback that was well hopeless but well yeah i mean that's just the way it is though in journals you have to be tourists and you can't put in it's a shame that probably many of the insights well you know i guess you put them in a thesis it's interesting that you know that was there i read it because at that time or shortly around then in harvard i was working on some similar things i'd already moved into particle astrophysics and was thinking about well it wasn't that because particle cosmology thinking about interactions in the early universe and what particles and how you could predict what particles might be left over and there's a lot of similarities to that to that early paper of yours um but it's still very yeah to to be interested in it that early let me ask you you said he went to good schools what's the dragon school i'd say elementary school it's it's is it a private or i mean i know all things are done so public schools are private in england so i don't know what yeah right it's a it's a private elementary school in oxford and um it's it since i was you know at the time it was just a good local school in oxford um it's become much more famous because it's had a bunch of famous alumni since that time but um uh it's i think for the year i was there the the ones that are probably listed in the it's probably me in a chap called hugh laurie who's an actor we were friends when we were well you were friends or something um and uh i actually was really funny because i i had no idea what happened to him and i have kept track of what happened to most people i knew when i was in in elementary school in kindergarten and so on and with you laurie i kind of knew he'd become an actor but i didn't know he'd become a particularly famous actor and so then i find out he's become a famous actor and he's doing this it's called house so the american television show right show and so so you know i say okay i better you know watch a little fragment of this so i switch it on and there he is and he's got his head cocked to one side and i'm remembering that's exactly what he did when he was eight years old he will walk around just like that so it's uh you know people don't change at that that level but no it was it was a um it was a school one one thing was interesting about going to school in oxford and even when i was in kindergarten you know these were it was a impressive group of kids you know if you know what they've done now it's kind of like uh you know they've done all kinds of impressive mostly academic types of things and that's what you get i guess you get to go to school with a bunch of professors kids yeah yeah that was a you know for me as a uh for a long time i used to say you know the smartest group of people i knew were the group of people i knew in kindergarten [Laughter] but often it you know i mean i tell kids one of the at a later stage that it's your peers you know when you're at university or anywhere else on the whole that you can get a good education anywhere a bad education anywhere but if you're going to choose try and choose a place where your peers are going to challenge you at least and uh and that and and because that's where you'll do a lot of your learning now obviously in kindergarten it's not necessarily that but it is interesting to me to think how different i'm always amazed when i talk to some people because our backgrounds are so different because neither of my parents sort of finished high school and and i i uh i have a friend of mine who's a physicist uh in in vancouver well i put his name ian affleck but he um he showed me a poem he wrote when he was in i think in kindergarten and he said when i grow up i want to be a doctor of philosophy and and i thought wow i would i had no i had no idea what a doctor of philosophy was probably from so many years so such a different upbringing but uh where did you grow up where did you grow up i grew up in toronto i was born in new york but i grew up in in toronto in in canada and um you know went to public school in high school i you know and there were no there there was maybe some private schools in canada but i wasn't really aware of them and um and i never even thought of going to the united states to to school it was these things never never occurred to me my parents wanted because because they hadn't gone to school and because they i i think because i had a jewish background my mother wanted me to be a doctor and my father and my brother to be a lawyer and and my brother became a lawyer my mother was for many years not happy that i wasn't a doctor but anyway that's some kind of doctor yeah i know but i wasn't the right kind i know i know but it wasn't the kind she wanted but uh yeah no she's gotten over that um but dragon school was one of the few schools you actually graduated from is that right in england they don't have the notion of graduation yes i i went through all the years of it and uh and i noticed it when i was reading i didn't know whether it was wikipedia or some other thing it always says and stephen prematurely left so you left eaton early yes yes i mean that was really what what you know i i went to eaton which is sort of this you know school that was founded before columbus came to america so to speak and um uh but it was a good school actually when i was there i mean i think it had gone through phases when it was kind of crazy but but at the time when i was there it was kind of you know i i applied there because it sort of had the best scholarships i didn't really financially that much need a scholarship but it was it was it was kind of a it was this very nice interesting group of people who were the the scholarship kids at eaton and um it's kind of a very small group and it's uh you know if you if you look at what happens to them they either go spectacularly or they crash and burn yeah yeah and uh it's it's some the uh um but uh you know it was an interesting group and um but you know i went there and um i was kind of doing this sort of side thing of doing a bunch of physics and learning about those kinds of things and i got reasonably proficient at that and so by the time i was like 16 it was like in england at the time you could have this if you if you got a scholarship to oxford or cambridge you could avoid doing the whole standardized government exams etc so that's what i did and um that was my kind of uh you know people told me at the time one of the things which was sort of interesting piece of bad advice was um you know oh you shouldn't go to college early you'll be so socially disadvantaged et cetera et cetera et cetera which which was kind of a you know in the what do you know how to do and not know how to do you know years later i've spent a bunch of time you know starting companies and stuff like this and you know i realized looking back when i was a kid i was always the organizing kid and so it was kind of you know this this oh you'll be so disadvantaged and not interacting with people and things not really quite right if you look in more detail it was kind of a a um uh you know i was the kid who was organizing the group of kids to do this and that and the other um and uh actually one of my yeah it's some um it's always fun to see some of the people who i sort of organized as kids to do things some of their later professions ended up being kind of what i organized them to do in some little project of mine which is which is kind of nice to see well that's interesting i you know one tends to think that socially well you were a little young you didn't find so i think it's different in england than it would have been a very different experience for in england in the u.s because in england you know with the tutorial system you can you is you can be be more independent minded and more independent um socially too i mean in the united states where it's all with large classes and everything else you really can't uh you're not encouraged to be so independent and so even if there were social age issues having to do with puberty and everything else i mean it may not have been so noticeable in a system where which was designed for if you could if you could learn on your own and if you could work on your own you could probably flourish more in an english system do you do you think that's right no i mean i think that you know the us has definitely gone for the full-service university of you know all you know everything is at the university i think that was less so and probably even still less so in the uk i mean look i you know for example the way that the oxford system worked i went to college in oxford was that you know if you you know all you actually had to do was the exams at the end of the year yeah and you know i i tried going to some lectures and i didn't find them at all interesting and i stopped going to them and i went to i went to a few graduate lectures that were some of them are pretty good actually and i i had kind of made this deal with this um uh group of experimental particle physicists that i would use their computers and their all their arpanet connections and things and in return for me doing some data analysis for them and so that was that was a pretty good deal and it was also it was also the only place in that i knew of in the uk where there was air conditioning was in the computer room ah so that's great oh that was a that was an added benefit well we're going to get to computers in just a second so it's almost a good segue but i th the um the interesting thing you you say about that that um uh it's intriguing to me that you that the um that the exam thing because you know that that in in my own life i can appreciate that because the only time i mean i had deals with professors in undergraduate where i could skip things but but the one thing i really liked about doing my phd at mit and i don't know if they still do it was that you know there are all these hoops you have to jump through and they're all these graduate diagnostic exams and graduate qualifying exams and et cetera and you're supposed to take courses for two years to take them and i at the time i gambled you know that i could learn enough on my own and i did them in my first term and pass them and it'll a lot and now of course it meant that there were gaps like like there probably were with you but it meant that i was at a stage where in principle i could have i could have been taken off early what i did was then waste time for a year or so but but it's a nice thing at least you get understanding that getting through the hoops you know is one thing and then being able to do other things is something else that just the passing exams is useful for passing the exams but really what's important is what you do after that in some sense well yeah right no i think i mean it look it was it was you know the fact that i did well in the physics exams as i say is is uh you know i'm sure in modern times it wouldn't even work because again it's kind of like like um uh actually one one of my favorite okay i have to this is just one of these crazy stories when i was doing this was when i was probably 14 or something like that i was supposed to do you know some standardized government o level you know standardized exam type thing i just do one on physics so i've done absolutely no preparation for this and i had no idea what the you know what the syllabus was and so on so i go do this exam and one of the questions on the exam is name two differences between the effect of electric and magnetic fields on on the on on electrons okay so i'm like okay you know it's e time you know charge times electric field it's you know charge time v cross b that's one difference what on earth and i realize you know i i knew at the time so i wrote down um something you know i said well electrons have magnetic dipole moments but they don't have electric dipole moments and um i said probably not what you were looking for obviously well we did they grade you on that did you uh i have no idea i mean you know i got a fine grade on the whole exam so i don't know but but i was just uh it was it was one of those cases where you know it's it's it's not clear that knowing knowing the you know the big story so to speak actually helps you in passing the exams i think in some of these things probably in more recent times it would be more like well did you do the course the way the course was supposed to be done rather than do you know the material so to speak yeah i don't know that's an interesting yeah it's interesting at some point everyone well at some point students have to make the transition from from doing well in coursework to doing to understanding things and and and to learning themselves and you made you know that meta discovery that you can actually learn things by reading books but of course that's a discovery that everyone who then becomes an academic of a graduate student has to learn that ultimately what's important is what you learn yourself which means you're not going to class and the way you get it well books or or paper or articles and to be able to that that's a very different kind of transition in learning it's great that you learned it early on my experience both for myself and students is that that transition is not so easy for students who have excelled most of the time by going through classes and then get to a point where they suddenly have to read papers and and learn things in a different way it's a it's a very different experience right and it's it's a different set of skills and unfortunately one of the issues is you know in an education system where you know you have to go through this particular sort of collimator so to speak to get to the point where you're allowed to do the kind of more researchy kind of thing you know people people will kind of die on the vine before they get to that point even if they would have been good at that and probably that would have happened to me i mean i'm very glad i got through the education system as quickly as i did because i'm not sure i would have survived it otherwise i mean you know the other thing in the kind of what one's good at and what one knows one's good at it's like you know i think you know early on i was always like well let me figure out what question i want to ask and i got you know in retrospect i was pretty good at that figuring out questions to ask which is you know i always thought that was kind of like oh that's obvious everybody does that but in fact they don't and in fact in you know in in academic research and sort of successful academic research to my mind that tends to be the bigger determinant of you know of of real success is can you actually you know solve the right problem not you know what about the mechanics of solving the problem and one of the things i've always been disappointed about in a lot of the education system is the fact that that strategy of what to study is absolutely not there because it's it's that's not what people teach you know people are teaching there is a trade you're going to do this particular thing and this idea of you know well actually there's this general area what's a question that might be interesting is tends to not be tends to not be taught and i you know again i always thought that was a kind of triviality except that it turns out you know that's the thing i've been that's the thing i've been doing all my life so to speak and it's it's worked rather well but it wasn't you know it it only in many later years did it become obvious to me that that wasn't quite as as easy as skill as as one might think well it's a very important scott you know anyone who's listening to me talking these things all will have heard me said and and i've answered this question a lot that to me all of education comes in the one and the biggest disappointment in education is that we don't get kids to ask what by asking questions questioning is what we should be teaching how to ask questions and and and encouraging that kind of thing and encouraging not knowing by the way including being a teacher and finding out how to answer those questions but but learning how to ask questions and is is vital and it's it's one i agree with you it's one of the biggest shortcomings in education in my opinion but it's a tough business you know i've i've done this thing i've you know for years i've done these things of you know with groups of kids and so on it'll be like ask me anything about science or whatever yeah i started doing that live streaming that as well in last year or so but but um one of the things that's always striking about that with with kids is there'll be some question and question number one it's like okay that's standard high school physics or whatever i can answer that yeah question number two it's like well i happen to know the answer that's a frontier physics you know frontier research question i know the person who is the world expert and i happen to run into them recently and i know the answer to that and then there'll be another question where it's like i know nobody knows the answer to that question because you know i've been curious myself and i've looked into it and nobody knows the answer and i you know i think that's really you have to know a lot to be able to pass those things out i mean it's gotten easier with you know the web and all that kind of thing but it's still it's still a a you know it's surprising for you know for a kid it's like like a good example actually this was one of my kids asked this question when he was pretty young was you know when there were dinosaurs could the earth have had two moons okay okay that's a great question right and and it's very non-trivial question oh yeah the answer is probably no but i asked a bunch of people who know about celestial mechanics and so on over the course of years and at the beginning of asking that question they were like we just don't know and then more recently it's like well there are simulations that have gone far enough to have a rotational period with two moons like that but anyway i would think right right well i mean that it depends how big the moons are of course another one that some kid asked me actually recently is is um why does the moon not have moons i know the answer that one that there aren't stable orbits yeah but in fact it's even hard to get a spacecraft to orbit stably around the moon there's another answer which is perhaps not it's a useful answer if it did it wouldn't be a moon because there would be a planet but but the thing that well it would be the only way it could have moons is if it dominated the gravitational influence in its around its surroundings otherwise as you say there'd be instabilities and that's one of the definition of a planet i suppose is that it dominates the gravitational uh influence of the region so moons don't remember the lunar reconnaissance orbiter is a moon of the moon yeah yeah it's true so it just doesn't happen to last for billions of years yeah as it turns out yeah yeah yeah but we're off in a very different way we're off in an a.m it's all right i didn't know where we're gonna go if i was gonna you know i was about to um you oh yes actually i'm gonna ask this i i'm going all over the place and we will eventually get to where i want to get but i hope two things though one you since your kid asked about the time when they were dinosaurs you wrote i'm going way back again i think when you were six or seven there's a picture of a of a of spikes on a on a stegosaurus about a drawing you wrote yourself and under over that you put the dawn of reason because you asked yourself how many spikes are there you want to explain why that was the dawn of reason oh i don't know that was just me me captioning or actually i think um i was going through quickly captioning these these pictures but it was kind of uh um you know it's the first piece of evidence of of actually kind of um thinking about things quantitatively that i could find i mean i you know i i had um uh i it was some uh i had a uh you know it's always interesting to look back on one's own education as one you know i've been sort of involved in education i have i have four kids i've you know kind of seen a bunch of bunch of things that that that go on it's um uh you know and then i think back to my own kind of education and and i also think back as i so look at people that i meet who are now young you know sort of what's the trajectory so to speak and i realized there are things that i would do when i was you know six seven eight years old which it's like oh my gosh that's the same kind of thing that i'm doing today like i remember the the um the realization that you could take two rulers and you could run one against the other and you could make an addition slide rule i mean i didn't know what um and this was kind of my um uh this was how this was one of the many ways that i failed to learn arithmetic because you know teachers are probably wondering why does he have two rulers on his desk because that would allow you to do things without having to do things i see yes but then there's a trend because you know then i've spent a large part of my life building tools to let one do stuff you know without putting in human effort so to speak to do it now that now we have the good segue because i that that steggy thing was an aside but i couldn't resist but see i'm trying to build for people maybe it's not useful because we're all over the place but i i want to talk about the context of what what you've done and what you're doing now and so there's three components there's physics there's mathematics but the other component is computers and i want to i want to find out when you what got you interested in computers and when i know i saw an inkling of that because i think i saw a computer tape in one of your uh scrapbooks there as a young person so you were clearly what got you interested in computers and when let me ask that question okay so i you know i i first saw a computer when i was like 10 years old it was a big mainframe computer at a distance i first got exposed to a computer close up when i was 12 years old when i went to high school because my high school had a computer which was a thing of the crazy british computer that was the size of a desk and you programmed it with paper tape and it had a very arcane machine code and so on but um it was um and then the question was actually the first really serious thing i tried to do with computers was to simulate that bunch of gas molecules bouncing around on the cover of the physics book and i was like let me write a piece of a program to do this well that computer didn't have floating point of arithmetic it didn't have lots of things the real irony is the program that i wrote was basically a cellular automaton program which is you know this kind of simple program that i investigated years later and but for a little uh coincidence of invariances and things like this i would have discovered well if i'd known what i was looking for i would have discovered tons of things that i discovered like a decade later right back when i was first doing this when i was 13 or so but you know i i i started using computers i wanted to do these kind of physics simulations but then i got into actually doing things with the computer for its own sake because it was a quite primitive creature and i was trying to write utility programs and so on i was very proud of my my uh paper tape loader which was a um so you know the paper tape would run through this optical reader and it would run very fast and it was it would you know wind up in a a a a wooden bin and you would rewind the tape and then run it through again but but if there was ever if it ever if that paper tape ever picked up a little piece of confetti that would kind of fill in one of its holes then it would just get the wrong data into the memory of the computer sure and so the question was how do you deal with that and so i i was in retrospect i ended up inventing some error correcting code that um would figure out as the thing was reading you know would accumulate data to figure out that it would have check digits and things i was very proud of that it was it was um you would literally pull the tape back in the tape reader and it would start reading again it would resynchronize itself and so on but that was my um that was my first piece of system software i said oh okay when was that probably in 1973 1974 when i was 13 14 years old that was that was um um and actually it was one of these things where where um yeah i mean that was just something i wrote i guess other people would use it to that point and it was probably my first piece of software now that i think about it's probably my first piece of um you know software tooling that ended up getting a user base so to speak are you i'm probably not a very big user base but the reason i i want to really go into this because because what you're trying to do now is so integrate related to programming in fact the universe is a program that i that i i really want to try and understand this a little bit more the my first assumption based on earlier discussion is that you had been fascinated by computers because they would allow you to do things that you didn't like to do and but was it that that intrigued you about computers what was it in particular or was it the power i mean i remember how seductive they were i you know we had punch cards when i was a kid in school and it was it was neat to be able to see that you could make this thing come up with answers that you might not have gotten otherwise uh and maybe not even know how it did it but what do you remember what it was that was so seductive to you about it look i i like technology and you know it's technology was kind of i liked the future and technology was part of the future and that was that was one reason why i like computers i like computers because it was you know i was was interested in doing these things like physics now at the time you know my very first computer i couldn't do serious mathematical computations on that computer that was a you know that was uh it was it was would be way too difficult on that kind of machine then but i think that um uh sort of computers for their own sake well you know i did things like okay i said i was an organizer kid right so they would have you know like open days at the school and things and so i would always organize the computer exhibit for the open day and so i wrote a bunch of uh little computer games and things like that and the people would come in you know this was 1973 1974 and all these you know various parents and so on come in and say oh it's a computer and they would uh you know it was very they'd never seen a computer before and they certainly never you know i had um uh some games that were actually his one that was uh uh it would print out on teleprinter it would print out two letters and then you would have to press a button depending on which letter was earlier in the alphabet it turns out if you run that fast people get it right less than 50 of the time systematically get it wrong at least that was my my experimental psychology observation of age 13 or something and so that was that was my the sort of my um probably my proudest exhibit for the uh for the um uh computer sounds like a science fair project actually yeah right right i probably got a lot of good data i did unfortunately i didn't really have a way to collect that data at the time it was more just observing what people did well you know it's interesting because i want to now we'll talk about when some one thing we converge because i'm i'm proud of this although you've not have they have the same memory of me but i will say by the way my very first sign real science paper after i got my phd um when i was at harvard was uh was actually done on computations it was numerical integrations using a hp 15c i my call you know all my colleagues had access to mainframes but i realized i could do this numerical integration would take a night for the calculator to do it but i didn't have any you know i didn't need it i didn't need it in 30 seconds and so it took took me a long while before i made it back to large larger scale computers and what and my first computer and the reason i want to bring this up is i do believe i've read that you've logged how many mouse miles you've also done okay but i believe i is this not true that i introduced you to the macintosh do you remember at harvard i had the one the first max at harvard you came visiting and you were very skeptical and i brought you down i had a because it was like a portable because it was 23 pounds and i had in my office and i think and you came in and i think you were very skeptical of it because i had the mouse and everything but i i i believe that i introduced you to the mac and i'm gonna and i'm gonna stand by very well be true you know i'll tell you by that time i was mostly using these sun workstation computers yeah and and i never you know i i had not used before mathematica came out in 1988 i had never really used a personal computer in a serious way i had had personal workstation computers yeah but you know and really even at that time when after mathematica came out you know it ran on the mac but i never used it on the mac i would use it for demos on a mac but i would actually use it on a song workstation um but uh that's that's a that's an interesting story i it's plausible it's um i mean that must have been well the mac came out in 1984 so that yeah that's that must be right before i got it i got one in jen a little after january 84 i was one of the first there was a lot there was a um there was a uh uh lottery because there's some people who wanted it and um and i wanted i remember i told my my friend who was shelly glashow about it and it really upset me because i really wanna i said there's a lottery and he he said oh really and he put his name in he got to be like number one and he got and what do you do with it did you use it no no that's what pissed me off because i really wanted it but i and i just won a prize as the gravity research management and it was exactly i was trying to figure out how i could buy it and it was exactly the same amount as the mac and so i literally won the prize and i and i and i and i uh and i gave the check back in but yeah so i had one maybe by april 84 or may or and you came shortly there afterwards when i was at harvard and and uh and i was very proud of it in fact i spent most of my time people would want to come in my office and and play and see it because it was very different than other computers and right and um and you came in and i mean you know that you're mentioning this this is vaguely coming back to me that's a good story yeah i think you know one of the things about the older generation the shelley glacier generation and so on most of them didn't know how to type and i remember you know like murray girl man for example i remember interacting with him about computers and things and he never wanted me to see him tightly because he couldn't type you know for a long time i was like proud of myself because i you know i used a typewriter from when i was early yeah you can read i can see it in your papers yeah yeah yeah right and i you know i got pretty fast at typing and actually actually what i really got faster doing was typing with two fingers because my fingers were not strong enough to do the full typewriter thing and then at some moment i i did the ten finger thing and i was fast typist and then i i used to think that's a great advantage that i have in the world that it all went away wow you know my mother thing came back with phones it now is useful to be able to touch oh yeah that's right but now with thumbs rather than four fingers generally however well right i've never got into the thumbs you know this is but this is probably a you know this is a disease from my early time it's you know me too actually i still use the index finger hold one hand and do it yeah but uh but i will say my mother you know again i told you my parents didn't go to college but the one thing she insisted i did learn how to do was type because she said you'll have essays so so i took typing class it was it was optional and uh yeah and i've always felt it was one of the great gifts she did me that i learned how to type early on yeah yeah a lot of people don't know how to do that now anyway look i want to get well we've now put together the pieces that will lead you to where you are i was going to say let me just say and i don't want to go into this now you didn't complete eaton then you went to oxford and it says you also left that prematurely as well and so you keep leaving schools prematurely because you i guess felt you'd gotten out of them what you did and then you went to caltech and and and actually did get a degree there finally um although in a very short time what happened was was it's easy to describe i mean i you know i got to the point was writing a bunch of physics papers and it's like okay i can go to college and do physics but you know i'm writing physics papers so what's the point here yeah yeah and um and and so you know it was kind of like accelerate things to the point where i'm i'm done with the education process as quickly as possible and and uh that you know that worked rather well actually it was uh it worked rather well only it only works well if you have people who recognize it like the people who happen to give you the good grades in that and that physics test was it what was it about cal tech i mean there are a lot of places that would have require i assume there are a lot of graduate schools that might have required more formal uh degree is it because caltech was so small that they were able to what was it allowed to get into i i by that point you know one of the things that was both a good thing and a bad thing is by the time i was like 15 16 years old i was you know showing up at all these physics seminars in oxford and things and i became a sort of known fixture on the you know on the international physics scene and then i was a i worked at the rutherford lab in england and i worked at argonne national lab in the us for summer and and so on so i kind of was was in the swirl of the kind of physics world which is actually turns out it's kind of disastrous in some ways because there are all these people you know i was a you know i don't think i was a particularly i was a somewhat brash 16 17 year old and you know when you're in sort of the international community and you're a brash 16 17 year old you turn the clock 30 years later and people still think of you as a brash 16 17 year olds i i you were very brash when i first met you too but yeah yeah so but the good thing is afterwards people don't think it's brash so much when you're older and you say the same kind of things as when you're well perhaps that's true right right no i think that um but but uh you know so what happened so i was i you know i talked to people these different schools and i was talking to harvard and princeton and caltech and harvard said oh if you don't have a college degree you can't come as a graduate student princeton said fine caltech said fine i i decided i'd visited prince and i hadn't visited caltech and so i figured i'll go to the place i haven't visited more or less that's that's that's more it was it wasn't the weather was it at all was it i mean which is very difficult i wasn't really paying attention i think caltech also had a slightly you know princeton had a more structured oh you have to do these courses and all that kind of thing and i i was like i don't really you know i i don't want to do this and i don't really need to do this and and caltech was was uh was quite flexible about that so it was um and i i did i i went to i tried to go to a course that dick fineman was teaching and actually he told me after a little while please don't come to this course anymore really so that was uh um why were you asking questions or were you or did you think it was just appropriate for you no he was the yes i mean i wasn't i wasn't being particularly brash but it was like i remember i i wrote him up something about the derivation of the weinberg angle yeah yeah and he's like don't come to my course anymore oh he says you don't need it oh it's not useful okay well and that was great about farming he would have not you know held a ceremony or anything like that if he knew yeah exactly that's a good thing the quality of good teachers to know what kids need to know and what they don't know need to know um okay look we've we've skirted around things we've already talked about fundamental physics in your and your interest and that's when we as i say when we first met almost was right around we met at the time when your life was changing it seems to me was around 83 84 suddenly went from the kind of what what the standard kind of fundamental physics understanding the fundamental laws by mathematical quantum field theory to suddenly i guess you'd already gone to the institute for advanced study i guess when i first met yet at harvard and you came up from there and then you did cellul you you discover i don't know whether it was then you discovered cellular automaton but but that it was even then it was knowing you at a distance that changed you it changed your life as far as i can see it changed your direction it changed everything about the way that you thought about the world as far as i could see that's true i mean look the sequence was this i mean you know i've been doing particle physics up until basically i got my phd in 1979. right you know a week after that i was like okay let me you know plan the future type thing and so i i realized you know i've been using all these computer systems for doing sort of mathematical computation i realized please don't do what i want how am i going to get something does what i want well if you really want it you should just do it yourself so i started building this thing called snp yes and so i spent a couple of years you know i was still doing some physics kinds of things at that time but i was mostly working on building this software system and let me let me interject for the public who i mean we've already gone so deep that people may have lost us anyway but but smp i mean it was in my mind at the time revolutionary there may have been other people doing it but you know computers were fine for doing calculations you know you plug you program them and then they work with with with des floating point and arithmetic and but but you didn't use them for symbolic when you sat on a piece of paper and did and did uh did algebraic or calculus calculations those were symbolic and computers just didn't do that and i do remember vividly the utility and also being amazed that it was possible to do smp was the first it was that sense i assumed for symbolic manipulation program was that was that what it stood for i think that and the idea that computers could actually do mathematics instead of just churning numbers they could actually do mathematical and help you do math real mathematics symbolic mathematics was shocking to me but and i remember my my colleagues began to say this can be useful because of course the one area of where and maybe this is the re and this is the reason i guess you got into it the one one area where you really d where you can get lost in the symbolic manipulations is the calculation of what are called finemen diagrams which i know you did and so you and and that i assume is that's what drove you to want to do smp is that is there for us i mean there have been there have been earlier computer algebra systems but they were always they basically had the feature that they could only be used for the babysitter that is they could only be used with with the help of the people who'd originally created the system exactly and also people i mean it was surprising to me the extent to which you know again it's one of these things where you never know what's actually hard and what's easy you know i i learned enough about computers that i could successfully use these systems without a babysitter so to speak um and and then i used them to do useful things and i kind of outgrew them and so i had to build smp i mean what was in retrospect pretty interesting about smp is it has a sort of a fundamental idea about how to compute that is sort of fundamentally symbolic more even more symbolic even than just doing mathematics it's really about symbolic expressions and transformation rules for symbolic expressions and actually very recently like the last few months i finally understood how to generalize the things i tried to figure out so back when i was working on smp there were all kinds of mysteries about how you uh it sort of evaluates things that transforms things until it can't transform them anymore and that process of transforming until you can't transform anymore and what about if there are different paths for transforming things that is a whole tangle of of difficult kind of uh ideas uh computational mathematical ideas and what's sort of ironic is that at the time when i was thinking about those kinds of things for smp i was also thinking about gauge field theories and it turns out that what i now realized is that the issues about all the different ways to do things between evaluation processes and smp engaged field theories are exactly the same problem but it took another 40 years to realize that okay we'll get to that because i know you keep talking about how you can you can basically get these law laws that we i mean for gage field theory as a central is the central symmetry and the central way of understanding all fundamental laws and and and i know there are lots of claims you make about that they're coming out of doing can't quite gage field can't quite yet get gage field theory although we kind of know how we think it's going to work the math is hard i want to challenge you on some of that in a moment but first first let me be more collegial and then we'll challenge but um and i should say to not do a short shift you're right there were people for example i think garter tuft and teeny weltman developed a schooner i mean a program to do to do uh uh symbolic some symbolic manipulation of of feminine diagrams in order for them to be able to do the kind of physics which eventually led to the nobel prize so they there were people working on it but you're right they had to be they were specialized there was no one who developed something that uh some bozo like me could come along and and just use right now and and the real idea of snp the important idea in the end was this idea of transformations for symbolic expressions which was a which is a very general idea about computing and that that's i mean it's kind of an abstract idea that i think people haven't fully absorbed even now 40 years later but it's it's also the core idea that our whole wolf and language mathematica stack is based on but i mean that was anyway but but in terms of the the sort of the the trajectory it was yes i i did that that was a it was a very interesting experience because building a software system is very different from doing physics because in physics it's like the world is the way it is you have to kind of drill down and try and figure out what's underneath it when you build a a computer language you're like let me write down these primitives now what can be built from those it's kind of very very much a more sort of uh uh you know you start from something it's like you start from these arbitrary things and then you build up from there rather than in physics you kind of the world is the way it is and you have to try and figure out how to sort of reverse engineer what's going on now you've explained everything to me because it's now it all comes to clearly to me because yeah that that's a very important statement because it's clear that what you switch to and it's an area where i'm not sure i agree with you with but it's what you've switched to is it's so natural to understand where cellular automata appealed to you and ultimately this new kind of science and and is is you're now claiming and and and then with cellular it's some simple rules and what can you do with them so it's exactly so that's what it's clear why that appealed to you because you'd been developing software that had never hit me before right right well actually you know it's always embarrassing when one tries to understand one's personal history because it was it took me a decade before i realized that connection myself but yes that's the that's some uh but but yeah i mean so so what happened is i was the big thing that i've been interested in for a long time and my early interest in statistical mechanics and so on was how does complex stuff happen in the world and so it was like i was studying reaction diffusion equations and i was studying these other kinds of mathematical approaches to that and they just didn't work and so i was like let me see what is the what what's the fundamental thing let me drill down let me understand what are the primitives from which i can build up that phenomenon and and that's what led me to i mean originally i was trying to model i was actually looking at self-gravitating gases and neural networks and it was like what's in between these two and i came up with these simple cellular automata which are just these rows of black and white cells which have simple local rules and cellular automated are good for many things uh self-gravitating gases and neural nets are two things they are profoundly not good for so it was kind of interesting that that that was you know let me just stop for one second because i do want to i mean we haven't tried to define a lot for people who've had to follow through but it but you sort of define cellular automata but i want to make it quite clear they're seductive and interesting because it they are that they're basically a set of squares blacks and whites and and and you and you um and there's a rule when you have let's say a black and a white together there's a rule for what the next row will be or and we have two whites together there'll be a or two blacks or or maybe four of them in a row so it's just a simple set of rules it tells you and then you proceed from one step to the other and what is surprising and seductive but i'm not sure as profound as you think but we'll have to discuss that what's surprising and seductive is that from a very simple rule of what happens if these two things are together maybe three rules you produce these incredibly complex patterns so i just wanted to let people know what and and i you know what cellular automata are and and i guess um i did notice in your in your scrapbook i guess it was a cover of nature or something but you know some of the early beautiful complex patterns you can get from these simple set of rules which must have profoundly affected you because i mean you know the the big question was what secret does nature have that lets it make all this complicated stuff and this was well you know it might be you know one's intuition my intuition have been you want to make complicated stuff you need to go to a lot of effort you need to set things up in a very complicated way this was a thing where you just randomly pick these rules very very simple rules you run them and and you know you kind of automatically get this amazing complexity and i you know at first i was like this can't possibly be right in fact i remember feynman actually was was i had a i had an interesting sort of exchange with him about this because this rule 30 rule which is a particular simple rule that produces this uh seemingly completely random in many ways pattern and i remember when we both that were both consultants at a computer company in boston called thinking machines corporation way back then and you know i had produced this big printout of rule 30 and it was there was certain features of it that had some regularities and so on we're kind of crawling around trying to measure a bunch of things with meter rules and so on and um and feynman you know takes me aside and he says you know look i just want to ask you one thing how did you know that this rule was going to make all this really complicated stuff and i said i didn't have any idea i just ran the experiment and that's what happened and he said ah i feel much better now i thought you had some kind of intuition that would let you figure this out no no no i'm just a you know experimental scientist so to speak at that level but but i think what what was surprising to me it's a very strong phenomenon it's a phenomenon where simple rules can do very complicated things it's a phenomenon that that you know i've seen all over the kind of world of possible simple rules when you go back and look and you say didn't people already know this and the answer is well they did kind of i mean like the digits of pi for example you know 3.14159 etc you know there's a rule for producing those digits but once you produce them they seem for all practical purposes random sequence of primes same type of thing there's a bunch of randomness and sequence of primes but what what people hadn't kind of gotten onto and it took me a while to get into was so what does it mean i mean the you know so you generate so there's this simple rule and it generates this very complicated behavior for example in the case of the primes people spent centuries studying what regularities you can work out the fact that the overall story is there's lots of randomness that was not relevant what was relevant was the stuff that could be attacked with kind of traditional mathematical approaches and things of saying what are the regularities so in a sense the you know what ended up with this book called new kind of science is you know what science do you get if you are really concentrating on this phenomenon that of what can happen with computational rules and that's kind of the that's sort of the the the thing that you can you can say we just don't care and people had seen these phenomena and they just said oh it's just noise we don't care we're concentrating on this on this particular thing which is very regular that we're looking for and and you know it's a question of what you're interested in for example talk about the second law of thermodynamics the second law of thermodynamics is the story of you know you start up a bunch of gas molecules and they're all in a very regular arrangement in a box and then you let them run for a while and then they're all randomized in the box and the question is what's really going on there because among other things the microscopic interactions are reversible so whatever whatever process could happen that goes from that that simple configuration to the to the apparently random configuration could also run in reverse why does that not happen and this this you know in the end it's this kind of fundamental computational phenomenon that explains how that works well yeah though i think you know boltzmann spent a long time eventually killed himself because of it but i mean trying to understand why that happened that way people didn't uh you know i i think i finally figured this out in the 1990s how this works and i think people haven't you know at the time when i figured it out i don't think anybody cared anymore and i haven't really i mean here's here's the story it's kind of an interesting story so you know you've got these gas molecules they're bouncing around a box they they you know they are in some configuration where um from that final configuration you can always in principle go backwards and figure out oh this final configuration was one that came from the simple pattern of molecules in the box this other one was one that didn't come from a simple pattern of molecules in the box um why do we why do we you know why is it the case that we don't for example end up with some configuration of molecules that will magically reassemble itself and unscramble the egg and things right and and so the answer i think is this phenomenon that i call computational irreducibility which we which we didn't really talk about yet we're going to get this you could start talking right now yeah right i mean so so take this rule 30 phenomenon okay so one of the things is you have a simple rule the simple rule tells you step step step you work out what the pattern is the pattern is complicated so you might say you know we're scientists here we predict things let's go predict what is rule 30 going to do and so you might say you you wheel in all of your sophisticated mathematical apparatus and so on and say we're going to crack it we're going to figure out what it's going to do and you try doing that actually dick feinman spent a while trying to do that for rule 30. um and he finally said okay i think you are on to something i can't i can't crack it but but but um the the um the way that um uh so there's this question of you know can you do what what one has been trained is sort of the the effort in science can you make a a sort of can you make a prediction can you say you know you've got a two body system you know earth going around sun you know from newton onwards it was kind of like we can just use math to figure out whether it's going to be we don't have to trace every orbit so the question is can you do that for rule 30 and the answer is well no you can't and we have in other words it's something where the computations that you have to do to work out what it's going to do you have to kind of spend as much time as doing it yeah computation as far as i can tell computational reducibility is saying to you have to be you know to figure out what's going on you have to basically do what's going on you can't there's no simpler way there's no simpler way to to to predict other than uh then to just do the experiment to let the particles do it there's no no no compactification of information if you wish that's what you call complicated it took me a while to get that but computational irreducibility is right and that's why it's something that is kind of a a it's sort of a a finer version of things like girl's theorem and a bunch of other ideas that um that have have um a sort of it's a it's a kind of fundamental fact about computational world it derives from an even deeper principle as far as i'm concerned which is the thing i call the principle of computational equivalence and that has to do with the following things so you take some set of rules and you say that set of rules when i run them it will do some computation and you might say well let me rank these computations which one is is the is doing the most sophisticated computation the least sophisticated computation the big surprise is as soon as you get out of a domain of ones that do obviously simple things that just make simple repeating patterns and things like that their claim of the principle of computational equivalence is as soon as you're out of that zone they're all equivalent in the sophistication of computations they can do and that ends up being a big claim because it says that from rule 30 to our brains to lots of things in physics it's all equivalent in terms of the sophistication of the computations it can do okay and that that claim is what leads to this idea of computational irreducibility because when if you're going to figure out what's rule 30 going to do what you're basically saying is my brain is smarter than rule 30. i can jump ahead it has to go through all its steps that i can jump ahead and that's what this principle of computational equivalence says you says you can't do um so that's what leads to this idea of computational irreducibility okay well we'll get we're going to get to computational this week i mean because the interesting thing i found frankly uh within with with the the the writing you've been doing and the statements about new kind of science and the physics project that you've been working on is one makes interesting claims based on computational irreducibility and bounded computation about what why the world may be the way it is but the quick question is but what physics does is predict how the world operates and so there's a there's a big gulf as far as i can see between general statements that may that are set tempting and seductive about that may make some that may seem plausible about general qualities of the world but that's a big difference than than doing things and and and so you know if if you jump ahead to our physics project for example yeah you know one of the issues there is is you know how does space and time work yeah and so you know we can talk about it in more detail but but in the end space and time are being built from this giant hypergraph that's this kind of uh collection of points that have certain relations between them okay it's an abstract relationship between points and then the fact that that when okay well jump ahead and my understanding of it is if and it's it's elementary i'm sure is that there are abstract relationships between points that um and there are they're sort of they're kind of rules they're rules that that govern the the inter the way the points are connected and there are many different ways they can be connected and if you look at all different ways you produce a structure that has properties that you would argue with like space-time is that is that not that's not quite right that's not quite right so so the basic idea is you have this hypograph that is basically uh how the atoms of space what the friend network of the atoms of space is yeah yeah what the friends it's not obvious you know the concept that space is made of something is not an obvious concept i mean that's not you know euclid didn't have that concept he had the idea he just put things in space and that's been kind of the common idea in physics for a long time this is kind of the atomic theory of space so yeah yeah so it's an idea that still is yet to be yeah it's it's a proposal let me put it that way yes okay right so so okay so then then you know you have this structure that is this kind of discrete structure just like molecules make up a fluid so atoms of space make up space and in this in this theory everything is space there is no there's nothing in the universe other than the structure of space so you know electrons are some kind of complicated twisty thing that is a feature of the structure of space and so everything is just the structure of space now what how does time work well this hypergraph that represents the structure of space it is getting rewritten all the time there's rules that just say if you see a piece of hypergraph that looks like this turn it into one that looks like that and do that wherever you feel like okay so that's so that's kind of the structure of space and time in these models and then the question is what then emerges from doing that and it turns out there are a couple of conditions and it's there's a complicated mathematical story behind it um which i would say is you know when people say how how nailed down is the mathematics the answer is it's a bit less nailed down than the proof that uh you know that you can get continuum fluid dynamics from molecular dynamics which has been 150 years and not nailed down that turns out to be a it turns out there's there's a lot of pieces of mathematics that one at the physicist level of mathematics it's beautifully nailed down at the mathematician's level of mathematics it's absolutely there's there's another century to go but but in any case the the thing you find is so you've got this thing and it's these atoms of space and they're being rewritten in all these different ways and then you ask what's the large-scale behavior of that system okay so it's similar to what happens in fluid dynamics you've got all these microscopic molecules bouncing around you say what are the what are the fluid equations what are the overall equations that govern a fluid okay so what happens in our case what happens in our case is those equations are einstein equations so in other words that they the the what emerges from the you know when you zoom up from this microscopic level with a bunch of conditions which we can talk about conditions yeah which is somewhat technical but but in the end those conditions i think are inevitable i think those conditions are not that interesting i think those conditions end up being for example you have to have computational irreducibility in the underlying dynamics of the system which is something that's pretty ubiquitous you have to have another thing called causal invariance that i think inevitably arises when you have observers in certain ways but in any case that the details are are one slightly complicated but yeah well that's what worries me to some extent as a skeptic is that um is that what you put in you want to make sure that what you get out is more than what you put in and you want to make sure that the conditions in some ways you know it's like they're very as you know and feynman showed it in general i mean you can get general relativity just by having a spin to field and and and and saying you know what so there are lots of ways to get actually there aren't very many ways together but what there are what i'm saying is you got to make sure what one of the beauties of physics it seems to me is that there are many there are a number you can look at a problem and what seems to be totally different ways of under of of formulating things lead to this lead to equivalent uh pictures yes that's certainly true and i mean that's certainly something that we're seeing very much i mean you know things like spin networks uh sort of various derivatives of causal set theory things like that all of these things seem to kind of read on the underlying structure that we have which is which is kind of encouraging all around but i think you know to me that the thing that you know the test of whether you know you say well you know we can give mathematical arguments for the fact that we get the emergence of generality the emergence of einstein's equations okay but i think the thing that is looking the most promising the most interesting right now is well you can actually use our models as a way to do practical numerical relativity so if you if you so usually if you want to simulate the merger of two black holes or something you'll do a bunch of symbolic calculation with with mathematica typically and then you'll turn the thing into this big piece of numerical analysis you've got these big differential equations and you know to make to to solve differential equations on a computer it sounds like you did that on hb 15c yeah but these days people do that on bigger computers you have to take these continuous differential equations these equations that are talk about continuous variations of things and you have to discretize them so that you can put them on a digital computer and and so then you have to do that numerical analysis and that's how people typically solve the einstein equations to work out black hole mergers and so on sure well so the alternative strategy is let's say we have an underlying model of space and time and that underlying model is is intrinsically digital we can just run it on a computer we run a big version on it on a computer and we say does that actually reproduce the same kind of thing that we get from numerical relativity the preliminary answer is yes and it seems to be interesting that would be fascinating because so my young fellow named jonathan gorad who's been working on this project with me um he has a paper about this and i guess this has turned into a whole bunch of people doing numerical relativity who are really looking at this in a serious way as a kind of a practical method for doing numerical relativity i mean it's somewhat ironic to me because i think many of these people say this is a good method for doing numerical relativity we don't really care what it comes from it's just you know this is a good way because what happens is in numerical relativity you have to figure out you know how do you add more mesh points to deal with the fact that things that space is changing more rapidly well in our theory the reasons the reason space is changing more rapidly is because there are more mesh points it's kind of like the whole thing is kind of generating its own numerical analysis so to speak so that's an example of of how you know to me that's an interesting form of validation for models is what i might call sort of proof by compilation if you can take some some existing thing and you've essentially got a compiler that goes from that existing structure like you know two black holes merging or something you turn it into your low-level code and then you find out that it produces the same thing that you had before that's encouraging we've now been able to do the same kind of thing for quantum circuits so that's a and in fact we now have a method for for optimizing quantum circuits that's a bit better than any method people have had by any other means and that's it's basically compiling a quantum circuit down to these multi-way graphs that we have and then and then going back and saying what does that mean for the quantum circuit so you know to me those are those are encouraging you know one thing you can do is the mathematical derivation you can always worry oh there'll be some limit that we took that wasn't valid et cetera et cetera et cetera but by the time you can actually do practical calculations that's encouraging it so it's even more fun when you can say and this is going to happen that you never thought was going to happen and then somebody can turn a telescope in some direction and see yes it actually happened and i think go on yeah no i mean i think i think probably our best you know what's what's interesting about those kinds of things it's a different kind of skill to figure out you know the sort of phenomenology given this theory where's the place where you're going to see the magic you know difference i think one thing that our model has in it that's pretty unusual is the idea of dimension fluctuations so in you know we usually think space is three-dimensional but by the time space emerges as this limit of this big hypograph there's no guarantee that it's precisely three-dimensional and the expectation is that in the very early universe the universe was infinite-dimensional and gradually kind of cooled down to be three-dimensional and the likelihood is that there are dimension fluctuations left over whether those survive to recombination i don't know um and then there's a bunch of you know detailed mathematical physics and electrodynamics and so on to say how does a photon propagate through those things all those kinds of things well that here this is the point i i think it's interesting because the question i have and the fact that you talked about dimensional fluctuation is an interesting one because one of the big problems that again i don't want to keep i keep coming back to feynman i don't need to but he that he disturbed him about string theory was it it didn't explain things he had to have excuses but but in particular one of the big failings is of course why is the work you know why is the world three-dimensional if there are many dimensions and it never really has answered that and and although it would be a great development if you could find that well so you're not claiming i mean i'm assuming you have to impose it that that there's three dimensions in here well no i mentions don't don't come out naturally from your model come on so so at this point so so here's the thing yeah first thing is i'm very sensitive to this issue of what do you put into a model versus what you get out yeah sure i've been in the business of trying to find absolutely minimal models for things so i really pay attention to that issue the thing that has been unbelievably surprising to me is there are no clueges so far every time you know it's something like how do gauge fields come out well you have to construct fiber bundles in this fractional dimensional space blah blah blah and you know every time one of these we've succeeded in actually constructing one of these things it works it's just like physics and there's not been any one of these things where we say oh but it's naturally 26 dimensional and we have to curl up these dimensions and do some cluj now do we know why the universe says we perceive it as three dimensional rather than six and a half dimensional we do not know that do we know why the electron muon mass ratio the neutron electron mass ratio is 206 we don't know that um what you know the question is what features of the universe are generic what features are specific what has turned out general relativity is generic quantum mechanics is generic um it looks like the sort of the merger of quantum mechanics and general activity is generic this question of you know how generic for example i have a slight guess that gauge groups may be generic that the you know subgroups of e8 might be a generic feature of the kind of structure of the system i don't know but that that's that's a question and and the the issue of why three-dimensional we don't know and and i think that the the thing that has come out that's kind of more on the very advanced end of of understanding what's going on is this question of to what extent the characteristics of of us as observers drive the the aspects of the universe that we perceive and to what extent that is something that um you know to what extent is the number three a consequence of some feature of the way that we are choosing to observe the universe that the average alien intelligence for example would not perceive yeah i just really don't remember you on that i just read your article about that and i mean which where where well which really comes back to what i said at the beginning which is that it looks very much like like one is saying in in this that it's not that these atoms are real atoms a space it's a formal structure it's a formal mathematical structure and in some sense it's like saying all of reality is a is an illusion and and okay so this is this is the thing that i you know i was very you know i i was saying at the beginning it's like when i was a kid i said the one thing i'll never do when i'm grown up is be a philosopher yeah okay and and you know i recently wrote something on the question of why does the universe exist yeah i know which is i read that because as you know i've written a book about it you know right myself so um so i you know i was very surprised to have anything to say about that i did not expect to have anything to say about it the number of people as you probably know you know even in the history of philosophy and theology and so on the amount that's been written about that is rather small it's been one of these questions that's just a bit too hard and the thing that really surprised me is i think i actually have something reasonable to say about it and it and the thing that is is you know that this physics project has kind of given evidence that there is a computational model of physics sort of all the way down and then the question the big question is okay let's say we've got this computational model we've got this rule it reproduces our universe et cetera et cetera et cetera then the big kind of copernicus style question is why did we get this rule and not some other rule why did we get for example a rule that looks simple to us as opposed to some unbelievably typical you know incredibly complicated rule that's a very you know we've been kind of trained in a sense to think that there's nothing special about us so how did we get the universe with the simple rule as opposed to the universe with the incredibly credibly complicated rule so i was really puzzling about that for a long time and and then i realized that in the structure of our models it is possible to think about a universe in which instead of one thing i didn't mention is kind of the way that quantum mechanics arises in our models has to do with the fact that they're sort of all possible histories are followed and and that's a that turns out to be an important thing and we then have to understand the kind of mind twisting issue of as observers embedded in that universe we have all these branching and merging histories our brains are also branching and merging so sort of quantum mechanics becomes the story of how does a branching brain perceive a branching universe so that's that's kind of a complicated thing but what i what i realized is that not only can one think about applying a particular rule in all possible ways you can think about applying all possible rules and and so then the question is what is that thing and you might say well if you apply all possible rules science is is off there's nothing you anything could happen but it isn't true yeah and your whole point is that there's some structure that arrives that it's a key not only is it not that any anything happening but your claim is that it's vitally important that you apply all possible rules and then you get and then you get a structure only if you apply all possible rules am i right because the reason for that is easy to see it's it's like if you apply all possible rules to all possible things some of the things to which you apply those rules you might have thought they'll just go off and do their own thing but actually you'll get the same result two different things you apply two different rules they end up becoming the same thing and so there's this whole network of equivalences this whole collection of essentially entanglements that you generate and so this object i think i'm going to call it the rouliad the limits of of this thing where all possible rules occur this this this object is so the thing about that object that's kind of a weird thing is that object is a formally necessary thing that is if you say there are you know it's just it is something where there's no choice in it it is just all possible rules all possible formal systems you put them all together you get this thing it's not something where anybody had to choose anything and then so you have this thing and then the question is well where are we and where's the universe in all of this and the thing you realize is that as we kind of try and parse if we are embedded in this thing we are trying to understand what's going on in this thing and we have to define this essentially collection of reference frames this way of this way of parsing what's going on and sort of the big claim is that that there are it is a generic thing that our way of parsing the things that go on will lead us to things that are like the laws of physics we know that our way of passing things which in our way is has certain limitations that are obsessed that's the key part again to get to for other people i mean it seems to me that the thrust of what you're arguing is that is that there yeah there are all possible rules there's computational irreducibility but the but the world as we perceive it is because we're computationally bounded and and that's why by the way as far as i can understand why we experience time in your argument but also why we experience the laws the way we do because in this in this computationally irreducible all possible rules uh rouliad i was going to say universe but ruliad let's just say um we are computationally bounded and and and we therefore experience the reality that we do with the laws that we do which which i mean is that is that a fair summary of what oh yes yeah i mean you know it's kind of like you look at gas molecules you could say um you know we experience gases as just you know pressure and temperature and things like that there is a different form of experience of gases that looks at you know i like that particular molecule and it's doing this dance with this other molecule and so on that's not how we experience it and you know our experience of the universe is very specific to our you know for example here's an example of something you know we look around you know you're in a room it's it's some number of tens of meters across or whatever um you know we're seeing light that comes from the edges of the room that light is reaching us at the speed of light it's reaching us in you know some number of nanoseconds by the time it's reached uh it's reaching us very fast compared to the speed at which we process that scene so to us we synthesize our view of the world as there is this thing that exists in a succession of moments of time if we were if we were much bigger than we are you know if we were the size of planets or something we would take the speed of light much more seriously if we had the same brain processing speed so to speak so it's kind of you know our experience of the world is pretty specific to our construction so to speak in our size and things like this and so you know i think one of the things that there are i think two key aspects of the kind of way we perceive the world one is that uh we have we are computationally bounded we're not able to go in and sort of untangle what's happening to every atom of space and the second thing is that we have the idea that we have a definite thread of experience that is we remember the past we know about the future we're thinking about things we're thinking about a single thread of time we're not we have a single kind of thing we're paying attention to and so on and i think that those are the two aspects of our perception of the universe and you know your average alien that we might meet and not be able to understand um might have a very different perception of those things and might have a completely different model of physics yes that's that's what's just yeah that's a very interesting point it's one that i find very disturbing and in my opinion probably unlikely because what you're saying is you're diverging of course from where you and i came from which is to say in some sense that the laws of physics the fundamental laws are universal and any and any and they are true properties of the universe and that any system will of intelligent beings will derive them and and and and what you're really saying is that no it's just a property of our consciousness and moreover our consciousness is kind of just a property of of a limitation of a complex uh computationally irreducible underlying system of abstract quantities and so it's all the universe is an abstract quantity we're an abstract quantity but not quite and it and and it it's really becomes quite ephemeral and it really well it's intriguing but but let me let's get there a second let me ask you a question though because i was really interested in your claim that this is is once once more as an old-fashioned kind and i'm an old-fashioned kind of guy i'm an old guy and i just say well okay what can you do with this and i was intrigued i mean that's much more more interesting to me than than the and then often the philosophical questions is what can you do that you couldn't do before and i was fascinated by this statements that you might be able to do improve on numerical relativity by this and i think that's interesting but it could it be that just as sort of string theory may not describe the universe what it has provided is a set of tools that have allowed us to calculate certain other things in ways we couldn't have so the utility of string theory is in my mind is it has allowed us it's given us tools to calculate certain quant physical things that we might have not been able to do otherwise is it possible that this is just mathematics it is beautiful mathematics but is it possible that your different kind of mathematics and your different kind of science is nothing more than a um might turn out to be not so fundamental but rather just a more interesting numerical computational way of handling physics problems i mean if it comes up to that would you be happy if it was just that well i think uh you know look this is all a big surprise to me frankly i didn't think this was going to work in my lifetime so so it's it's a you know it's as far as i'm concerned it's all bonus so to speak okay but but you know the fact is that um in the you know the question is if we have a model that sort of has structure all the way down we can say well it's just a model and that's the nature of models models are formal representations of things the only question about a model you can ask is is it an approximation or does it is it the whole thing all the way down yeah and what it's looking like so far is it's the whole thing all the way down now an interesting question is how does it plug into lots of other mathematical physics you know spin networks causal set theory you know uh categorical quantum mechanics all these kinds of things here's the really remarkable thing and the thing that i think people are in those different fields are really excited about is we're sort of a rosetta stone for all of those fields that is what seems to be happening is we've got a machine code that all those different approaches plug into so you know in causal set theory for example that's an idea where you're just saying there are these events that happen in space time and you throw them down at random and then they have certain relationships between them people in that field have been a bit confused about well what you know there are issues about how random can they be and why are they why do they satisfy the relativistic environment to be fair it's interesting but it hasn't really gone very it hasn't really done it so what's happened now is uh this is another jonathan gorod production um what jonathan did was to show how our models provide an algorithmic way to generate causal sets so that's not too surprising what's that i guess that doesn't surprise me i don't know why no it's not because you're talking because it's relationships between points right exactly right exactly so but in causal set theory that's a theory of randomly thrown down events now we have this is an algorithmic generation of these events when they are algorithmically generated in this way all these things that people had wondered how does this work in causal set theory they just work and so now there's a whole big adventure there in doing quantum gravity using that etc etc etc and it's really very beautiful and it's something where it's it it feels like once kind of got this this thing that's a machine code that's underneath these very elegant pieces of mathematics probably also string theory i mean we don't yet know about that but i'm pretty sure that's going to be in fact the the one ridiculous pun fact is that a sort of simplification of our models is not rewriting hyper graphs but rewriting character strings and i kind of i was writing this section and something i was writing about this and i was writing you know the case of strings and i thought i can't write that because people are just going to be irreducibly confused and i thought but let me actually think what is the limit of these character string theories and i realized i'm pretty sure it's stringfield theory and that hasn't yet been proved but i think it's going to be the case that the pun is actually reality um and and so that stringfield theory ends up being a particular limit of kind of a simplified version of our model um and so it's a very different way of it so it is a it's not it's a different way of doing science which one could say is in contra distinction to the the the idea that you're that when we we do physics now we it's it's it's a central part of physics that our models are not complete in fact the normalization group that that that no one model describes the universe at all scales that then as the scales change the models change and it's fine and we live with that and it's a central way that governs the old-fashioned way of doing physics which the kind of way i think about it and this is completely different this is completely right it's base and in some sense it has it shares with string theory that same claim which string theory would say it is a complete model of every of a down to at all levels there's nothing there's nothing else much more extreme version of that string theory is a much less extreme version of that string theory already has you know a lot of structure we're yeah we're a much more outrageous version i mean i think the three degrees are a much more outrageous version i'll agree with that right i mean i think that you know in the history of physics you know i was kind of interested to kind of trace this through as we were kind of presenting this project i was trying to get when did physicists get so humble in other words when did physicists stop believing that there would be an underlying theory of everything and you know the fact is that people believed that for a long time and it was only you know it's a comparatively recent thought that you know people like descartes believe that there would be a fundamental theory of everything and i think that the the concept that you can't turn physics into mathematics that there is something you know almost theological beyond kind of beyond physics there is something out there that we are not going to be able to turn into a thing that we humans can wrap our arms around so to speak that's an interesting almost i would say theological uh kind of kind of concept of saying you know there's really something else out there it's not all just something that we can we can wrap our arms around and and sort of make it maybe yeah but the feynman's argument might be you know that's like you we can wrap our arms around it and it's like the layers of an onion each layer we have a mathematical way of wrapping our arms around it but then there's a new layer and it requires a new mathematical way and there's a new layer into that and then and that and simon says he didn't want to know all but he just all he wanted to do was understand the next layer and maybe that's a little more humble let me remind you that actual onions in the physical world are finite yeah i know eventually peel it all off and there's there's i don't know what there is in the middle actually i have to say i haven't done it but there's something in the middle and then you're done and i think that's that's a you know it is a fundamental question i'll tell you what's in the middle stephen it's an atom of space clearly yes well quite i think that one thing about atoms of space though that's a little bit um uh kind of disquieting is there's nothing permanent in the world that is the items of space are being rewritten all the time so it's the only thing that's permanent is you know a space like singularity in the middle of a black hole that's an atom of space that just got stuck that's an atom of space that's not getting rewritten there's nothing more that can happen time has stopped so that's the only that's the only permanent thing is you know well let me ask you i'm going to wrap up but but um i can't resist you say that generically is general relativity and generically the quantum mechanics well since since so far except for the claims of string theory we can't find a mathematically consistent quantum theory of gravity if both quantum mechanics and gravity are generic features of this then this should be a theory of quantum gravity right that absolutely is and that's i mean that's that's well are you saying it is or it should be or you cannot i mean i i think it will be and there's a bunch of people now working on on trying to fill in those those those features and you know i think that that the the big surprise is that in the end general relativity is a kind of theory of how things work in physical space there's this thing we call branchial space the the space of quantum branches and quantum mechanics ends up being in our models the same theory as general relativity so the deflection in in you know there's gravity in physical space and mass and energy deflect paths of things in physical space that's what leads to gravity in in branchial space energy also deflects things what it deflects is gd6 paths in in branchial space and that deflection the the kind of coordinates in branchial space are essentially quantum phases so a deflection in branchial space is a change of a quantum phase which is in fact exactly what the fundamental path integral of quantum mechanics is one about so it's a you know there are many details to this but i think the big picture is that's how it works that these things are actually the same theory and and so you know the effort right now i mean a bunch of people are working on this is is to try and fill in so what happens you know what is that interface like between kind of the quantum side and the gravitational side how does it relate to ads cft how does it relate to er equals epr all these kinds of things that have been popular in physics it's looking like we're actually getting you know it's it's fairly clear that the correspondence between like ads cft and things is a correspondence between physical space and branchial space that these two things are part of the same object well you know it's oh it's it's i know you're excited and it's interesting uh i i understand there's a lot of things that are looking like and and and and general ideas which i've now learned a lot more about because i wanted to prepare with some some knowledge to be able to discuss with you reasonably competently after all otherwise i would be wasting your time but but it still seems to me i guess it's it still seems to me it's premature it i understand that you're exciting but but um as you as you're saying one of your your arguments despite these developments fundamental physics always seems to resist this advance that we're making and i suspect the the resistance is still the the challenge okay show us something we didn't know i mean so and that's still a challenge and and you're right we don't know where it's going to go and i and and i think it's i think the things that you know we're looking at and they may not be the right things to look at the first thing we're trying to do which is a typical thing in history of science is can the new theory reproduce what the old theory said sure and and and in fact we doing better than that we're actually making practical methods for computing things in the old theory using the new theory and doing it better that's kind of a copernicus story no that's great are you doing it better or is it the potential to do it better is that actually it seems like okay in the case of quantum circuit optimization we're definitely doing it better okay in the case of numerical relativity that's still a mushy that's still a mushy i kind of figured that okay but but i think that the um uh you know the thing that there's the question of where will the first places be where we can actually see definitive new effects so dimension fluctuations are one thing is there a place we can see that another one is just as there's a maximum speed of light in our models there's a maximum quantum entanglement speed and i i increasingly suspect that in quantum many body systems it may be possible to see the maximum entanglement speed that we may not be too far you know the problem is in our theories quite possibly the elementary length is like 10 to the minus 100 meters so that's really small it's really small compared to what we can what we can detect so you know those are another case which looks promising is that a critical black hole when a black hole is spinning fast enough that it's almost revealing a naked singularity and so on right at the point where it's kind of at its critical uh you know angular momentum that essentially we have a gravitational microscope that we can essentially see through to individual causal edges in this in the structure of space-time that what will happen is as the black hole spins faster essentially a piece of the universe will break off and right at that point just before it breaks off we'll see this thing which where we can kind of see through to the molecular dynamics you know we'll see like a fluid you know you how do you know that a fluid is made of molecules well you have to discover brownian motion or you could also be be flying a space shuttle and you could be going at mark 25 and you could realize that the hydrodynamics that you might have learnt doesn't work at mark 25 it matters what molecules there are so now the question is what's the analog of hypersonic flow for um you know in black holes and things and that's you know so there's there's pieces like this and um you know those are the i don't know which of those will will break first so to speak and maybe there'll be i mean we have only one parameter in our models basically which is the maximum entanglement speed equivalent to the elementary length equivalent to all these other parameters if we knew the value of that we would be able to make a whole bunch of predictions of things now there may be predictions which are hopeless to observe with current technology but we know what what was going on we just need that one parameter and i don't know where we'll be able to get to that well okay well it's ambitious and it's clear that you're that that um that no i what the thing that has most surprised me at recent times about this physics project is the following thing so i thought you know we do this physics project it might be interesting for physics if there's an application of it it's 200 years in the future you know we're not even close it's um you know i wrote a thing about going fast in the speed of light and using kind of maxwell demon-like methods in space to go faster than the speed of light and it's like there is no way you know even if this works we're 200 years away okay another you know maybe that's that that that that's a very good way to think about this because physics came out of natural philosophy um and it you know when you could argue about philosophy as it turned into physics and and as you pointed out in some and i don't mean this in a pejorative sense when i read what you're writing and i think when you're thinking about what you're thinking you may be at the stage in your picture of of producing philosophical pictures and it may and and and it may take a long time to discover if if they're physics pictures i guess you see that's not what's happening i mean by the time you're running black hole merger simulations that's not philosophy okay yeah no that's true if you're if you're you're right and if you can do that as i say i'm going to continue to be a skeptic in the sense that i'll say this is a really useful numerical tool and that that's great and that's wonderful discovery and very useful and it's clearly a new way of thinking about how to handle manipulating space time whether it is a new picture reality i'm gonna you know i'm gonna still say it's like people would have said that about planck when he fit the black body spectrum with photons yeah even planck said that about planck he didn't show the photons were real or whether this was just kind of a trick yeah but but the fact that we don't know yet doesn't guarantee but i mean it's always nice to make analogies to wonderful breakthroughs and this may be maybe a useful breakthrough and it may be a wonderful breakthrough but i think the jury's still out would you well i mean i think that the thing that to me is most interesting so first point is so far no clue jesus that's really big yeah it's it's like it wasn't necessary that that would be the case it could be that you know as we as we investigate and do a bunch of complicated math it's like oh gosh it's got to be 26 dimensional yeah whoops nothing like that has happened so that's remarkable to me second point is the thing that is kind of the most interesting to me right now is the underlying sort of meta model that we're using which i'm calling multi-computation which is this whole business about multiple threads of time and all this kind of stuff what is what is really remarkable to me is that meta model is turning out to be applicable to a ton of other things to matter to distributed computing looks like to chemistry molecular biology possibly to economics possibly for linguistics okay why do we care the reason we care is that we get to leverage physics in those areas that is if you want to make a model of economics you want to make a model of molecular biology right now you you don't get to talk about time dilation and you know space-time singularities and things like that but if there is the same underlying meta model that applies both the physics and to these other fields you get to transport kind of the successes of physics to these other fields so even if it turns out that you know we didn't make it all the way to the bottom that this isn't the final sort of theory so to speak that there's still another layer of onion which i'm i'm having a hard time understanding where that onion would be but that's you know be that as it may i mean this this is a thing you know i'm enough of a student of the history of science that i'm i'm well aware of kind of you know though there isn't any another layer of the onion but we just didn't know where to look for that other layer so to speak it's it's not um but but i think this is the thing that that that being able to see these correspondences with other fields this is going to be super powerful and it doesn't really matter at that point it's basically just using it's doing something which is again not what i expected it's leveraging the success of physics to make physics like models of other fields well if that's good that would be useful again i'm i'm i'm i have to say in some ways i'm more skeptical let me tell you the reason when i was a kid i remember go take a sociology class and i and i and and i suddenly thought oh they're using all these terms like physics terms maybe we could because i was always interested in science maybe we could use physics to create you know really good science of sociology and then i realized it's just analogies that don't work and and and social systems can't so so i'm you know and one of the biologists have told me one of the reasons that well i know why physics is so much easier because you can generalize and and whereas biological systems you're gonna can't often generalize each system is quite each cell each organism it's much more difficult to make the kind of beautiful generalizations we make in physics in biology which is one of the reasons why it's so much harder but so i'm surprised if it works well you see see in biology one of the one of the kind of inspirational ideas is this if you look at genetics before 1953 it was a mess of course people were saying there are all these effects etc etc etc and then there was an idea which was a single molecule can store a whole bunch of digital information dna and and that then makes that whole area much clearer so right now one of the issues is in molecular biology there are all these processes and you can kind of look at all these giant wall charts of you know all these different uh kind of signaling pathways and all these kinds of things what is the big picture of what's going on what actually matters and i suspect that there's a different thing that matters that has to do with causal graphs and all kinds of things like this that it's just something like the oh actually a molecule can have digital information on the molecule there is something different that can matter in molecular biology and that becomes kind of a paradigmatic change that then enables a lot of things but but you know i i'm curious to ask you you know if you say uh you know the question is is there a bottom level so to speak in other words what um you know we have a model for physics let's say and it reproduces everything we know right now and maybe it makes some predictions that turn out to be right et cetera et cetera et cetera what would or wouldn't convince you that we're we're done that that's it what would convince you that that that there's nothing left there's no more miracles so to speak there's no there's you know because that's what in a sense when we say there is a physics there is a rule for the universe you say well whoops there might be a miracle that happened yeah that doesn't follow that rule i guess yeah well i guess i'm a little um you know i i it's a good question and i think i think one it's i'd have to think about it more carefully to give you a real answer but i think the first answer might be somewhat similar to what you would say is if if there were no adjustable parameters if there was if if you could reproduce it all with with no adjustable parameters then i would be much more i'd be much more willing to suspect that it was a complete theory right so what i think is going to happen is that in this ruliad of all possible physics is effectively we just as we live at a particular place in physical space and not in another place so we live in a particular place in rural space and not in other places and so in a sense the theory is going to say this is the space of all possible theories the particular one that we're at we're going to have to say why you know if you say derive from first principles why do we live on earth rather than alpha centauri you can't derive that from first principles it's not the kind of thing you can derive from first principles and so i think similarly it's going to be the case that what we're going to find is we live at this place in rural space we can say why you know we can give evidence for why that's the place we're living at but we're not going to be able to derive from first principles why the universe appears to us the way it appears to us well that's very similar to the to them not only to multiverses but to anthropic arguments in some sense it really there's a lot of i mean that i mean you know from a very different path including the path that i've taken uh you come up to a somewhat similar argument that there may be nothing fundamental about our universe it's one of in fact actually i was intrigued by one of your conclusions which is why does the universe exist because more or less because it it it can and ultimately it something has to and in some sense it's not too different than than a multiverse idea that that that that um you know i mean we that's another conversation that's true right now it's a i mean this is a this whole issue about sort of necessary truths and the the fact that there are formal things that just by the definition of those things have to be that way is a little bit different from physical arguments about how you know you can look at a space of parameters and so on it's a it's a different kind of thing um it's a i think it is a significantly philosophically different thing but it's a will well i would like to have that conversation again i mean i first of all i thank you for taking the time i've always you know i've known you for a long time i i've admired you as well because you were able i mean in particular you know there was particle physics but then you took this thing and really made something i mean real mathematica and you know and and and it's something i i'm always admire people who do things that i couldn't possibly imagine myself doing and that's one and so um so i and i admire the the dedication that you've given to this trajectory you're working on and it's a noble and ambitious trajectory and it and most noble and ambitious trajectories don't succeed and i but i hope you know for sure because because i i see what i'm doing you know i've basically done basic science and i've done technology and i've i've alternated between those things about five times okay and it's turned out that the place that i've got to could only have been reached i think by the path i've taken which is just so weird and it's so you know i mean for example this physics project there are so many ways that this project would never possibly have happened and you know because it requires both having the tools and the knowledge and the you know knowing physics and knowing about sort of theoretical computation et cetera et cetera et cetera and you know it's the the question it's sort of an interesting experience that i've had because i've had you know i think after my very first paper everything i've done since that time it's turned out i had the right intuition so it's it's uh you know it could be and i'm usually one of the things you know it maybe maybe there are asp this i have to say of all the different things i've done this is a place where i am more certain than ever before it's just too many things fit together this is not one of these things where where it's like it's a put up job you know you've got to say well i've got to tweak this to get quantum mechanics i've got to tweak that to get you know event horizons or something it all just comes out and it's it's very it's really surprising i mean i it's not what i expected i you know what i expected was you know i had thought about these ways of thinking about sort of underneath space and time and so on i thought that you know in the next 50 years we would be at the point of being able to little tweak little pieces and we have some understanding what was going on the idea that we actually get to the point of being able to make real statements that can be compared to you know actual experiments and so on i thought that was far far away and it's it's ended up being much you know i think much closer now now you know to me i think i i would pose to you as a piece of kind of um philosophical homework because i think it's interesting is you know you i suspect believe in some kind of idea of induction as a way to deduce what's true about the world and the question is with induction you never reach the end you can never know that you got to the end of the whole thing and so i'm curious and i and i i'm poking you a little bit because i'm saying basically i think that any claim that you haven't got to the end is essentially a theological claim and i think that that's some you know that's something where unpacking that i think is sort of interesting because it's like how do we know you know we've done a bunch of experiments we we can do this you know how do we know we got to the end and you know i think that's not uh you know it's not it's not obvious what the answer to that should be and in a sense you know just just to say that that i think one thing you have to understand is what is a model of physics so you know the physical universe is a model of physics it does what it does yeah of course yeah and so the question is to make a model of physics what we're doing is we're saying uh what is a model of physics a model of physics is something where we humans can wrap our brains around something which gives us a narrative that explains why the universe does what it does that's in a sense it's like it's like computational language design we have to we have to figure out there's this thing out there that's the universe and then can we have this language for describing it that that makes us convinced that we understand what's going on i think i think as you unpack that i think you'll i think i i don't know because i haven't done it but i'm i'm guessing that this question about where is induction i mean i actually had a suspicion for a while that um uh some of these things about the structure of this ruliad that there would be essentially you could prove limits to scientific induction that basically that certain aspects of decidability in this thing would be essentially a a proof and it may still be correct that there may be a proof that there's certain kinds of things that are unknowable to scientific induction um and and that's uh that'll be fascinating i guess you know when i when i was thinking about when i just threw off the notion that our universe is an analog model of itself i guess the difference is you'd say it's a digital model of itself i suppose is that yes yes and that's the big difference well look you know i think one of the reasons the difference maybe i haven't to the question of how do you know if you have a complete theory i guess um right now you think you're much closer to that point only when you get close to that point i mean that does that philosophical question become relevant if you're if you think you're very far away it's not so relevant so i guess why uh you know a philistine like me i just figure i'm so far away that i haven't worried about that philosophical question yet right well i mean you know and similarly for me this question of why this universe and not another is not something that i had really thought about until you imagine you might hold in your hand a model of the universe you don't really care why this one and not another you know it's clearly an interesting question i don't know if it's true i seem to remember when i wrote a universe from nothing i think you contacted me and were interested in that question i i think i remember you wrote me an email and and maybe that maybe then you were beginning to think about those issues sounds plausible yeah i mean i was i was i've been you know i have to say it's been it's been an issue that's been bugging me for a long time and i was just really surprised that that i had anything useful to say about it and and uh that was uh anyway i hope i've done justin i hope i've done you know i try i wanted to give some justice to the listeners who've been who have been patient enough and i realize there's some areas where we've we skirted over things that are maybe technical and and some people may have been lost but i hope i get we were able to give the flavor and give you a chance to not only talk about the new work you're doing but also to see the unique trajectory of you as a human being which is fascinating and i thank you for sharing that and i hope you've enjoyed it it was a fun chat nice to nice to chat it was good oh good i'm glad you found it to be nice steven and uh yeah and i hope we can be together in the real world or the virtual real world depending upon whether yeah some day some day sunday where are you you're somewhere in canada i'm somewhere in canada and um and it's on the east coast of canada but i'm sort of keeping it a little bit of a secret but i'm in the most beautiful world i'm somewhere in massachusetts so that yeah i'm close by and and and when we're offline i'll tell you where it is and i hope you'll come visit us fair enough okay take care [Music] [Laughter] [Music] i hope you enjoyed today's conversation you can continue the discussion with us on social media and gain access to exclusive bonus content by 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