The Science of Interstellar with Science Advisor, Kip Thorne

here's Einstein predicting gravitational waves laying the foundation for a laser and 100 years later his gravitational waves are found with lasers yes Einstein was kind of smart from the time I first started working on gravitational waves until we succeeded it was 50 years some things take a long time we do build on each other and none of them by themselves are smart enough this Nobel Prize really belongs to a thousand people if I can see farther than others is cuz I've stood on the shoulders of giants whove come before me and that's the nature of

science it's very promising uh but it's going to continue on into the Next Generation before the ultimate success is had very very very probably this is star talk I'm your host Neil degrass Tyson your personal astrophysicist and today we're featuring one of our one-on-one con ation this time with professor of theoretical physics Kip Thorne Kip Thorne welcome to start talk a pleasure to be with you Neil oh my gosh we are uh coming from your home office in pasaden California a wonderful office my son designed this part of the house and built it and my

brother designed and build all the furniture these are really useful people to have in the family it's a wonderful family they're the Practical ones I've actually known you for some time not that we were beer drinking buddies but I think we've drunk beers together in the Canary Islands yes we did okay okay I I stand corrected uh but my first exposure to you was you were one of the three authors of this book called gravitation and we used to joke of course it was the only book where you learned about it just by carrying it

around and I think we probably wrote it before you were born possibly possibly uh although I'm older than you might think uh this book is a graduate level treaties on basically Einstein's general theory of relativity at the time I acquired the paperback of it which this is it's tough making a paperback this thick but this has the exact proportions of what was then the Manhattan yellow pages so we we we used to call it the phone book yes uh just affectionately may I may I add it was brilliantly conceived because I don't know if you

can notice on camera there are uh Tabs are different colors say white and black and they represent two different paths through the book one is sort of the elementary path and one the more advanced path except it all looked Advanced to me at the time so whose idea was this to come up with this book coming up with the book I think it was sort of grew out of discussions that uh Charlie misner John Wheeler my PhD adviser and I had a few years after those are the three co-authors three co-authors and uh so it

it sort of grew organically in the uh that's the best kind of yes projects to have 1960s and early 1970s MH yes I was born before the 60s oh really so uh on here is uh Charlie misner who's at was at the University of Maryland yes and so my copy of this I had you sign it and then I spent a year teaching at the University of Maryland so I quickly went over to his office and had him sign it but before then I uh I started out in graduate school at the University of Texas

where John Aral wheeler had they stole him from Princeton I think is what that or or him from Princeton I think yeah that's an accurate statement and so I had all three of them sign it in fact John Wheeler's course that he taught in general relativity is where I met my wife wow yeah she has a PHD in mathematical physics so we met in relativity class just thought I'd say that very romantic place to meet you know very romantic very romantic and John Wheeler used to give out uh a penny if you caught an error

that he committed on the front board so I have one of his pennies I I don't remember it was not a big thing it was like it was a typo or something what the WR the written version of a typo but um so uh anyhow it's just Delight to uh meet again with you and what prompted this was our uh you know you have a lot of accolades of course including the Nobel Prize okay but but more importantly than that you were science adviser on the film Interstellar I was more than science adviser yes you

were you you were executive producer I was more than executive producer it it grew out of a treatment that Linda opst an ex-girlfriend of mine oh and I Lind big producer of sci-fi films yeah she a big producer of films of a wide variety but Linda and I dated in 1979 80 and uh she was uh too high strung for me and I was too nerdy for her but we became close friends wow and who knows that why didn't I know this why did no stop why didn't where would one learn this it we need

a gossip a physicist gossip column is that right yeah it was some years later after Carl Sean who uh set us up on a blind date by the way that's we met okay some years later Linda called me up and said would you like to brainstorm with me for a movie wow and uh we did and that's how Interstellar was born so was that at the time it really was was the creation of the Nolan brothers because they took what we had given them uh which was basically a structure uh and a venue for the

movie The warped side of the universe and they ran with it and changed our story almost completely and made it into a great film I don't but the the all the seeds came out of Lindon and me at the time I mean you're you're Professor Caltech the Richard fan professor at Caltech now Emeritus CCH is a pretty high level Place how was it viewed for you to say guys hold on I'm going to make a movie now what is that how is that received by your colleagues uh I think they were all enthusiastic bch is

a different kind of a place than some other more stuffy un oh okay okay I never hung out much at Caltech I couldn't judge the mood or the tone yeah no look we're on the edge of Hollywood uh the Hollywood folks come over and you know Big Bang Theory was based on calch right call it calch what did they call it they did call it calch in the first few uh episodes okay and then they stopped using the calch name because the shirts that that's Hollywood speak for the attorneys oh yeah the stiff shirts yes

yes up in the office the shirts got scared that they might do something on a screen that the Caltech shirts wouldn't like and the Caltech shirts might sue the the Hollywood shirts so they stopped using Caltech name and in the in the film which I adored um what's it called Real Genius yeah Real Genius they were at Pacific Tech all right that was the where all the smart kids were so of course pasaden is in like I can't say foothills of Hollywood but you you you have a proximal awareness of this huge industry and you

know that science fiction matters as a as a genre well and some of us love it I love it I'm I'm signed up every time and so uh Interstellar uh I think it introduced many people to authentic gravitational physics for the very first time well Ander Celler was unlike almost any other film I I think were precursors in 2001 and in contact Yeah Carl San's contact Carl San's contact and and the the point is that science lots of science was baked into that film from the very beginning because of the way it was born and

because of the close close collaboration I had with the Nolan brothers and buil in right from the very beginning baked in baked in and and a science that uh in which the guid line that we worked from is that uh nothing in the movie would violate well-established physical laws and all the wild things would at least spring from science in some manner any good science fiction story should be but there's not enough well there's nothing wrong with fantasy uh films the Harry Potter style for example it's just a different genre by the way that film

uh you you must have known you said okay we we're going to have to help people out give a guy a break okay they're trying to see the movie they're trying to follow what's going on what the hell's happening why did the guy get old who why is he younger than his mother what's going on and you up and said let's help Let's help a person out yeah well it I would put it a little differently it was I saw it as a superb opportunity to use this uh film as a motivator and to get

people interested or intrigued in science and then there would be a bridge to uh the science through this book admit it you created a Gateway film it it was a Gateway film yes so the science of interstellar yeah New York Times bestseller Kip Thorne with a forward written by of course Christopher Nolan and it says spoiler alert uh this book explains the Fantastic Climax and ending of interstellar and so let me tell you how that came this issue came about Chris said to me early on I would like to make a film where the ending

is as mysterious as the ending of 2001 Space Odyssey that's a high bar that's a high bar but he greatly admires Stanley kubri and and that film and so somewhat later on as we were talking about the ending and we had lots of conversations about the ending he said well you can explain the ending in this book that you're planning to write so he volunteered you to write the book well no I was already planning to write the book but uh he identified that as the place where the eny will get explained he was not

going to explain the he would leave it mysterious not in his film he was pulling a a kubric on us that's right uh in fact we uh interviewed Christopher Nolan if you're an archive diver uh we've got a whole episode with Christopher Nolan even before Interstellar was uh produced and as we know so many of his movies he plays with time in some kind of interesting way if I remember correctly he talks about how influential 2001 Space Odyssey was to him back in 1968 that that would have been yes um so let me ask you

just a couple of things about the story line and I and I have I have an issue with it if I may but I know I don't know if I ever went public on this but I figur I I'm in front of the man himself so I if I have an issue they would be here and now you're GNA you're going to get turned into a journalist who's challenging me going to give me a tough time yeah I got to I can't this can't be just all okay softball let play a little hard ball so

I guess my issue we're looking for a planet again this is in the themes of the of the movie we're looking for a planet like Earth similar enough to Earth that we can send people there to continue our civilization and our species is that a fair characterization of a plot line of the plot line okay and it turns out there's like a wormhole that can make that happen a little faster because otherwise you don't live long enough to travel the distances with the Rockets available to hit those destinations okay I'm just thinking this blight on

the crops that was starving everyone on Earth requiring that we jump ship literally jump ship to go find another ship another spaceship Planet it seems to me that whatever effort it takes to find another Earth travel through a wormhole ship a billion to terraform it ship a billion people there whatever that effort is seems to me to be a bigger effort than just telling the biologist come up with a serum that could fix the crops even today we have full knowledge of crop gen genomes just fix it whatever is just go in there Nip Tuck

the DNA fix it isn't that cheaper easier faster than worm holing your way off this planet that's my that's where I'm coming from do you think that all problems can be solved by humans with human technology a time scale you have such faith in come on so I'm The Optimist here okay so let let me describe this this characterizes how that this movie was done so when it was uh Jonah Nolan Chris's brother who came up with the idea that he wanted a blight or something like that and so we said okay we will bring

together the best biologists we can who are experts on these kinds of things uh put together uh uh most mostly calch biologists uh and and we had a dinner and we brought out very expensive wine for them to drink and we set up a recording in vino veritos okay in truth there is wine yes in wine there is truth yes and uh so uh we I had a conversation that lasted about three three or four hours at the Caltech Faculty Club the aam about what could we what would be the best backstory here there are

two types of blights there are generalized blights that attack lots of crops and there are different species ofs lots of different species of crops but they are generally uh fairly benign blights and then there are uh uh blights that are very specific to a particular crop and they can be very lethal blights uh that may totally wipe out that species on Earth even but basically for Earth to Sur Earth and life on Earth to survive uh you better not have a vicious generalized light light but according to the biologists that I discussed this with they

didn't know of anything that would prevent the development of a very vicious generalized blight so that's what occurs in this movie and it's something that that biologists have never seen but they cannot uh rule it out rule it out okay so let me repeat what I think you said said they have vicious lethal blights that attack a species less lethal generalized blights that cross species boundaries and they can't rule out a lethal flight that would cross species that's right and so that's what's happening in this what's happening in the film and okay and that's what

they just biologist in this in the back so there's I'll give you that okay okay so anyway there this film is full of backstories because of the way we did it it's as I say again it's unlike almost any other film and that uh these issues were uh like that vetted were vetted by the world's best experts in the process of the writing of the screenplay okay as we're diving into Kip Thor's impressive work one thing is clear his theories have reshaped our understanding of the universe so you might think the latest Nobel Prize for

physics would go to some like Thorne but it went to computer scientists instead their contributions to machine learning is undeniable but still a surprise for the world of physics some reports focus on the Godfather of AI regretting his invention While others don't exactly see the problem in moments like this access to diverse perspectives is critical making ground news essential there're a platform created by a former NASA engineer who saw a bigger problem down here on Earth than up in space and the way we consume information and how heavily that shapes Our World Views ground news

responsibly uses technology to add Clarity to a world full of opposing opinions by showing perspectives from around the world how reliable sources and blind spots so you can see important stories barely receiving attention here's why that matters critical thinking drives the pursuit of understanding complex Concepts it challenges established beliefs and it's the only way we can make new discoveries so for those of us who are curious enough to dive into New Perspectives now is the perfect time to give ground news a try take advantage of their massive 50% discount on their top tier Vantage plan

and get access to every feature we've shown and more for only a limited time use our Link at ground. news/ StarTalk or scan the QR code to subscribe as we continue exploring Kip Thorn's groundbreaking series remember ground news can bring that same level of critical thinking to how you stay informed now back to the show well I got another one okay you're one for one all right when they're on the black hole Planet okay uh and then they see this wave coming okay it's Miller's planet planet the planet orbiting gargantuan Gargantua okay the strength of

title forces are highly sensitive to the distance you are to that which is causing the tides highly sensitive okay but every illustration I've drawn or taught about Tides they're not so peaky they're much broader in their representation on a planet and so there they are waiting in water but then they see this single wave come and if it is a single wave as we've seen with tsunamis it actually takes water away from what's ahead of it because it can't just be water out of nowhere it's drawing water from its vicinity so my two issues was

if it's tidal would it be that peaky and if it's any kind of wave how could it still leave the water laying around its vicinity and then just be that big as it came by so there is a type of wave called a solitary wave on water that was you could tell me you brought wave people together and had that lunch what you talk no this particular kind of wave was discovered in the 1700s wow by I've forgotten who a a a physicist in in England who saw a boat that was being pulled by horses

and it was just starting up and it created this wave that traveled down a channel a canal uh and it was peaked like the wave in interstellar though the wave and Interstellar I have to admit it was exaggerated there was exaggeration there was some exaggeration in the peak but but it traveled down the channel it never broke most waves at the ocean they break they okay just so we can get the picture because we're talking about centuries ago uh when you see a channel that would be a Channel or canal canal and then there's a

toe path on the side and then and then people and more likely beasts of Burden would drag things through the canal cuz themselves don't typically have current drag a barge down the canal a barge exactly and so this barge was dragged down the canal uh and it was just starting up and it created this wave that uh on the startup on the startup and it just headed out and just took off and went down the channel and this this guy got got on his horse and he followed down the channel and it went and got

to love curious physicists Nothing Gets By it went went down the channel for I I don't know a mile or two uh without changing its shape without breaking without breaking and so the theory of these waves is is that there there are two different effects that cause a wave to steepen uh or disperse and the two can balance each other out stable sort of a way and give it longer life and give it long life uh and so aside from the issue of friction if for there were no friction it would just live forever and

keep propagating in a very stable way it's there's a mathematics behind it something called the COV de equation that this is a solution of but anyway these waves then so so that equation I presume has both kinds of waves uh in equilibrium somehow represented the STA W the dispersion and and and the steepening the steepening is due to nonlinearities the dispersion is due to the fact that that the higher wave the higher parts of the water travel faster than the lower parts of the water if you're at the ocean you see a little tiny wave

it travels quite slowly you see a big wave it travels quite fast and that's why the the crest of the wave will actually break before the rest of the wave gets there is that part the reason that's right that's right unless that's being balanced out by dispersion which is anyway I love it good good I'm loving it I'm getting a slightly confused but anyway the two the two effects balance each other and to produce uh this very stable uh solitary wave and so in the movie but in for this stable solitary wave the height of

the wave is and I forgotten the number but it's something like six times higher than the depth of the water got it so there's a problem now in the movie because they're walking around in shallow water and this wave is high and so it's got to be deep water okay but they're but but they're on an island this is the backstory again there's always a backstory oh so they're on a a Subterranean a sub surface Island yeah you got to read it in my book They're they're they're they're on they're on on an island and

this wave defract around the island they hardly notice the island at all so so again there's it's it's all explainable except there is a bit of exaggeration the the in the CGI uh wave was made uh somewhat more Peak somewh give you that it's a movie and it's Hollywood but what you're saying is this wave might have been caused by some effect other than the tital forces of the black hole Yeah well this wave is caused in fact by the fact that this uh time is is very is much slowed on this uh yes on

this planet so the planet has been uh put into the orbit around Gargantua not that long ago is seen uh on the planet though it's a long long time ago was seen from far away and it is it's like Mercury like the moon keeps one face toward Earth or Mercury capes one face toward the sun due to Tidal effects this planet is distorted by tidal effects and it's swinging back and forth it has not yet settled down uh to one face toward the planet and that swinging back and forth is generating this wave that's all

in the book he weasel out of another one okay there's an enormous amount of Science in that I must have missed that when I went through the book and one last point you didn't study it carefully enough one last point we uh took our show to Oxford yeah recently and uh interviewed a an Oxford I think it was a postto and I name Andrew Mumy postto and he showed us a recent paper he published I don't know if you've seen it recently like within the past 18 months and uh he's a the radical physicist and

he in alerted me something I'd never knew uh I love the field but it's not my active professional field that in the vicinity of a black hole there is an innermost orbit because of course you can orbit any source of gravity even if it's a black hole but for black holes in particular there's an orbit within which the orbit is no longer stable and it will spiral into the black hole itself and according to his calculation to get the time dilation necessary in this scene with the black hole Planet which was huge remember they were

on the planet for like 15 minutes or whatever how long 1 hour on the planet is seven years up at high seven years up in their spaceship okay and the guy who they left there he was like gray and unshaven and everything and we're like oh my gosh there's some serious einsteinian physics going on here his calculation showed that for that difference for that extreme difference in time d requires that planet orbit so close to the black hole they would be on an unst in the unstable Zone and so I I just thought I'd tell

you that my calculation says otherwise so so so and where's his Nobel Prize the other guy the formula is in the book in in this book yeah so so you so we don't have to go to your graduate textbook for that well not for the answer okay if you want can to to derive the formula that's a lot of work so let me tell you the story behind this got a story okay so Christoper Nolan says to me one day he says I want the uh hero and Cooper the hero in this movie to go

down onto this planet Cooper played by Matthew MCC that's right Professor Bran's daughter is played by Jessica Jessica chest Chris Christopher Nolan says to me he says I want in this movie that one hour on Miller's planet is 7 years up at very high orbit or back on Earth he prescribed that and I said to him that's impossible because the planet will fall into the black hole he said go do a real calculation I've already learned that your offthe cuff reactions can be wrong and I should not trust you unless you do a real calculation

there's a good Hollywood producer go back and give me the answer I'm looking for well well and so I went back home and I did a real calculation and I was amazed uh that the last stable circular orbit which is what we're talking about uh is uh if this planet spins fast enough last circular stable orbit can have as high a a a high a red shift as high a time difference as you might wish but that requires the dilation it requires black hole spin extremely close to the maximum possible Spin and so in the

book I give the formula for what is the uh the spin of the black hole that is required to produce a given amount of slowing of time did not know that and and that and so that it's an approximate formula but it's a formula that can be derived though takes takes a fair bit of algebra okay so the one one would just learn about would probably be that the lowest stable orbit around a nonrotating black hole that's right and that's a clean that's that's a clean problem and that clean problem that's that's what I was

thinking when this when I knew that if I made the black hole spin that it would get closer but I couldn't imagine I could not imagine that it that nature would provide it a orbit for a black hole that spins fast enough that they could provide this much of a slowing of time it does it does at least unless I made a mathematical error but I don't think that's like because I because I used Mathematica okay you had tools to help you do this because check my calculations because it was it's not just an analytic

solution well it is an analytic solution but it's very complicated it's very complicated you okay well it's a power series solution in the end I think the our hero character is inside the black hole we come to understand understand this and he has access to a timeline that wouldn't otherwise be available to him and he sees his daughter's bookshelf well he's no longer inside the black hole where is he when he's doing this so this is the key thing that's not explicit that you only understand if you read my book you didn't read it well

enough busted no I I I read a lot of it let me say I what I read I read some of the biology it was a long time ago too yes okay so so he when he gets inside the Black Hole uh he is scooped up by a a a spacecraft that was built by this Advanced civilization that provided the uh the Wormhole uh to him and to humanity and it's called the Tess act and it's a tesseract is a four-dimensional cube four spatial dimensions and that's why in there you saw uh I guess the

past and future all kind of simultaneously it felt very higher dimensional that's right this Tess he so so so let me back up I'll tell you a story so early on in when we were working on the film uh uh Christopher Nolan said to me he wanted uh to take his hero back to Earth Cooper back to Earth uh by a different route than the Wormhole 10 billion lot years away from the earth how's he going to do it if it doesn't go through a wormhole he said well I want to take him back faster

in the speed of light and of course I say to Chris you can't do that it violates the laws of physics he says go do a real calculation I said I don't have to do a real calculation and so we discussed this for a week and then he uh threw in the tow he said okay I believe you and so what do we do and so I said well uh you put him he goes inside the black hole he uh gets deposited on the three-dimensional surface of a four-dimensional sphere and this four-dimensional sphere is a

spacecraft that go can go into the bulk into the higher Dimension and it take goes out of the black hole not through the Horizon it can't do that it goes up go through the fourth dimension up through the fourth space Dimension or what's called The Fifth Dimension in the movie this time is the fourth dimension and goes back to Earth and the distance back to the Earth is less than the distance between the Earth and the uh Sun even though it's 10 billion light years inside of our universe up in the bulk it's a very

short distance and so he can get back quickly this is the higher dimensional SpaceTime in which we are now having this so he gets back very quickly uh riding on the surface of this four dimensional sphere he said I like it all entirely except I'm not going I'm going to use a four-dimensional cube instead of a four dimensional sphere that's a tesseract yes and uh so that's what happens and you when you see Cooper out there sort of flailing around uh at the beginning of the test scene he's being carried by the test back to

Earth but you don't know that's what happening until you read my book by agreement between Chris and me that's that's the only way anyone's ever going to know so anyway he's carried back to Earth and then everything is happening when the cact is docked uh in the higher Dimension beside his uh giving access to his life in that past time that's right so it's it's docked in his home by his in his daughter's bedroom okay so now he's pushing books off the shelves that land on the floor and through some clever cryptographic judgment he's spelling

out words with the first letter of the title of each book okay here's my issue I had no problems with tessaract black hole fourth dimension five Dimensions how does he know the title of each book from the other side of the book so I don't remember that's how he's actually uh he's pushing books out I know he's push I know he's pushing he's pushing B out from this side yeah yeah and all he sees is the other side of the library I I guess I had forgotten that he was uh spelling things out based on

the first word oh you forgot I forgot or I didn't know or you're are you're wrong so that was one of my I little issue there that that that one I don't know oh okay okay I don't know okay so you're you're three for four he he Pro he probably has he probably has a photographic memory the other side of the book what's this I hear that you can use a wormhole to travel backwards in time does the math check out does the einsteinian physics check out and does that mean I will just show up

a younger version of myself and shake my own hand is that what you mean by that or do I no longer exist in the time that I left for my younger version of myself to see that and wasn't there I didn't Hawking put forth a time travel prevention conjecture or something was what what's going on there so this is all an outgrowth of my phone conversation with Carl Sean uh when he was uh working on the novel for contact where uh he triggered me to start thinking about wormholes and then having started to think about

wormholes it became pretty obvious to me rather quickly that if uh I give my wife car Le one mouth of a wormhole and she carries it at high speeed in a rocket ship out into space and then back and I keep the other wor mouth at home and uh if she she sees me age by 50 years back on Earth well she AG is only one year going out and coming back but if we look Through the Wormhole at each other uh we see each other aging at the same rate just imagine uh we hold

hands and we look at each other's wrist watches they're it's ticking away at the same rate so through the wor Through the Wormhole we've aged at the same rate we're the same age but uh looking throughout outward through outside the world a normal universe all she's aged one year and I've aged 50 years something weird has happened the Wormhole has become a time machine I just go over and go into her mouth Wormhole mouth and come out I'll meet my younger self okay now Hawkings said this is no we're not going to allow this there's

some conjecture yet to be discovered that'll tell you you can't do that well so know the story we get there you're going too fast I'm going too fast sorry so so I then I talked to friends at the University of Chicago physics it's crucial to talk to friends they tell you where you're all at you tell you when you made a mistake they straighten you out and they pointed out to me that uh it might be that when the time machine is turned on it'll self-destruct basically they said I said I don't understand they said

go do a calculation so I went and did a calculation and the issue is and they had guessed and basically that's oversimplified but they Bob gach and Robert Wald at Chicago anyway it turns out that at the moment that you can first time travel the F the first thing that go goes through it can be vacuum fluctuations of light say that Ender her mouth of the Wormhole come out of my mouth and go back and arrive back at the her mouth at the very moment they started out now you have twice as much at the

same place in space and time so this is a runaway so it's a runaway and so they you now have twice as much and then it goes around again now you have four times as much goes around again so this runaway uh builds up just like the the feedback between a microphone and a speaker precisely and it just runs away it just runs away and runs away and and this runaway shows up in the quantum mechanical calculation that that I did you're bumming me out dude together with San Kim a Korean post of mine okay

I want to be a movie director and say go hiip go home and figure out how to do this give me another pull another rabbit out of the Hat here well anyway we discovered this Stephen I think and one of his stepen Hawking uh and a student of his I think had more or less the same Discovery at the same time except step probably just did it all in his head because the way Steven is anyway so uh then Steven and I started corresponding about it by email and talking on the phone about it and

so forth it appeared to me looking at at the details of the calculation that uh in fact the explosion if I designed the time machine just right the details of the explosion this explosion would not be strong enough to destroy the Wormhole uh and Stephen then showed me that that I was wrong and we argued back and forth for a while finally we came to agree that the explosion becomes strong enough that quantum gravity enters in and then holds the answer tightly in its grip and so we won't know whether time machine self destructs until

we understand the laws of quantum gravity let me be on obscure but then we come to the Hawkins Cosmic sensor ship conjecture that's what it's called yeah he the conjecture that in fact in the end the laws of quantum gravity won't save the day the Wormhole will be destroyed and any time machine any advanced civilization makes will be destroyed when they try to turn it on by these vacuum fluctuations uh and thereby as Hawkings says keeping the universe safe for historians of all species it reminds me of the ultraviolet catastrophe MH where you run the

calculation this is going to blow up how does this even work and then outcomes the discovery of the quantum which Saves the Day right and this is could be a calculation waiting for another branch of physics to open or or another progress no in the known branches of physics to resolve the loo team has has perfected a technique called quantum Precision measurement which is based on manipulating vacuum fluctuations uh in order to circumvent the uncertainty principle and so this business of manipulating vacuum fluctuations is something we do in modern physics if memory serves Carl Sean

came up to you and said for contact I want to go far distances quickly how am I going to do it can you cook up a wormhole for me Carl me uh in well back in the 80s when he's writing the novel obviously the no pred of the movie that's right and he said that he wanted uh that he has written he'd already written this the book The Novel it was already in page proofs and he said I've got this novel it's in page proof the publisher is not going to be happy if I change

it but I really need some help see what the truth is and then we'll figure out how to deal with this and uh he said that I have my heroin traveling through a black hole to get to the star of AA and I said that's rather dangerous there's a singularity in there okay there's a singularity in there and you can't get through get to the star of Vega so what you actually need is a wormhole uh but there is is an issue that wormholes implode they collapse so quick that nothing can get through but I'll

see if I can figure out how how to hold the Wormhole open just for you Carl and so and so I was go I was going with it's like rent a physicist right it's like whatever your needs are so so I was getting in a car that that morning to ride uh with my uh former wife to our daughter's grad uation up at Santa Cruz so Lind Linda was said I'll drive and you calculate so okay so she drove and I calculated and I fiddled around and then it became fairly obvious turns out somebody other

some other physicist figure this out sooner but I that's the usual thing with me I I figure it out then then I go see did people know this before or not so so anyway I figured out that uh you if you had what I like to call exotic matter that repels gravitationally and you put it inside the throat of a wormhole that can hold the Wormhole open it' be like pushing it outward that's right it basically repels the the walls of Wormhole to hold them open and it turns out that that that will do it

but you have to have you have to have enough exotic matter to hold the Wormhole open and uh I deduced a formula for for how much you had to have Bas and it basically says the following uh if you move Through the Wormhole let the record show he's about to describe how to make a wormhole no no only how to hold it only how much EX got matter you that sounds like a recipe to me but so you you travel Through the Wormhole as close to the speed of light as you possibly can just very

close to the speed of light and you you add up all the the energy density all the way through the Wormhole of stuff that's in the Wormhole the net has to be negative and then you can hold the Wormhole open so it basically means you've got more negative energy than there than positive enery we have nothing known as exotic matter oh yes we do what yeah and so that oh is is this in your basement is what do you mean oh what what what do you mean oh yes we do what what okay what what

is our exotic matter that would fulfill this purpose so so if you should we turn off the camera now are are the is the government going to show up on your in your driveway okay go well I I learned about this from Yakov barovich zovich in Moscow zovic zovic was one of the inventers of the Russian hydrogen bomb okay and I learned this from him all right okay he was really brilliant I learned about about vacuum fluctuations and how important they can be and what how powerful it can be if you can manipulate them and

uh so and so if you take a box and you remove everything that can possibly re be removed from the box you're left in the end with tiny fluctuations of everything that c possibly could have been in the box so electric Fields you have fluctuating electric Fields fluctuating magnetic fields fluctuating protons electrons fluctuating NE Ty the grass Tyson so this this creates a form of pressure inside the Box well so the ne there's Vanishing pressure and that Vanishing energy due to renormalization that's a Nast that's a nasty word in physics but uh the the uh

well me we can you can measure energy by whether it produces gravity or not and uh although these fluctuations that are there it you can think them as particles say particles of light flashing in and out of existence randomly so why isn't this not the virtual particles that people speak of so it's virtual particles it is that okay we we've spoken about those on our show before okay so you have Green in fact so you have virtual particles uh in the vacuum popping in and out of existence popping in and and you can't stop it

you can't prevent it however you can take fluctuations from one region and borrow them and put them in another adjacent region for a little while or if you put an electrically conducting a sheet say a sheet of of of superconducting metal here then that will suppress the fluctuating electric Fields parallel to the metal because they would create an infant current flowing in that metal and that would that that would wipe out the the electric field parallel to the metal and so uh is is that an element of the Kazmir effect yes that's the Casmir effect

is yeah where you have two parallel plates evacuated between them right and there's a point where they actually feel a whole other Force attracting so what that Force really is is uh in the region between them uh the vacuum fluctuations are suppressed and so you have negative energy in between that energ negative energy is sucking them together and you have you have you and they can do work on you if you you're holding on to these plates uh and they attract each other put energ to resist you put you put energy in as they go

as they go together they do work on you the electric electromagnetic field between two plates in the casmer effect uh is exotic okay and so so you have this in your basement is what you're telling me well I don't have it in my basement but but physicists do this let me just say as a side remark H Having learned a lot about vacuum fluctuations we in ligo in our gravity wave project get to that get to that I'll just just make the remark that we have we the loo team has has perfected a technique called

Quantum Precision measurement which is based on manipulating vacuum fluctuations uh in order to circumvent the uncertainty principle and so this business of manipulating vacuum fluctuations is something we do in modern physics and it is something then that uh you can imagine you can ask can a very Advanced civilization manipulate vacuum fluctuations adequately in order to make enough exotic matter inside a wormhole to hold the Wormhole open and so I POS this as a a question to my physicist colleagues uh stimulated by Carl San and want him wanting to send his heroin through a black hole

I said no use a wormhole and so we got a pulled it open and so physic colleagues please help Carl and figure out can an advanced civilization do this and the answer is we still don't know uh 40 years later now we still don't know right well we're doing magic compared to what anyone thought was possible 50 that's right years ago certainly the dawn of quantum physics we're on the Centennial of the decade of quantum Discovery back in the 1920s well I had was very close friends with Carl San and I've developed close friendship with

Christopher Nolan Chris has a very different background than me he knows a lot of science but he's learned all by browsing the web and uh he uh and he knows it well enough to ask me hard questions that's just like you do uh but he asked them first so I have the answers now so so he and and have inspired me to ask questions that and then I sort of translate to and give to colleagues because my colleagues are smarter than I am my my my uh role is is to pass on interesting conduit for

this conduit for interesting question for my colleagues to work on so dude you can't leave well enough alone Einstein says maybe there are gravitational waves emanating from major gravitational disturbances in the universe and you got to go up and find them but you're not the first to have attempted this right I at the University of Maryland there was Weber I think I think what's his first name Joe Weber of course who had a cylinder if I remember correctly uh where he was trying to measure whether if a gravitational wave washed over it he could detect

a distortion in the shape of the cylinder I think was the goal yeah well he would the gravitational wave would drive vibrations of the cylinder end to end vibrations okay and uh so he instrumented it to search for uh changes in the amplitude and phase of vibrations of the cylinder cylinder is at a finite temperature so it's always vibrating a little bit because it's the finite temperature and uh so and so he instrumented it uh with what's called at electric transducers transducers that he that he glued around the uh middle of the cylinder that when

they were squeezed they would generate an electrical voltage that he could measure and there they're amazing things this p Electric transducer is just absolutely amazing you squeeze them a tiny tiny bit and you get a big voltage out uhuh and I mean Joe Weber was tremendously creative he was and he I think he was working on that while I was at the University of Marland I was there in the 80s I think he was still working on it yeah that's right so he began working on it uh in the uh late 60s early 70s and

uh uh announced that he was seeing possible evidence for gravitation waves in there was a lot of skepticism at the time if I remember let let me I'm sorry he started working out in the late 50s early 60s announced in 69 that he was uh seeing some possible evidence of gravitational waves and a number of other physicists around the world built similar detectors and the bottom line in the end after a period of shaking out was that others were not seeing grav ation waves and that's the only way science works is one person's result is

not a result until somebody else a competitor somebody else who uses different wall current somebody from another country you need you need multiple verifications but on the other hand uh Weber Joe he started the field he triggered this work the Theo the approach that he invented for searching for gravitational waves was the dominant approach from then until uh the 2000s and the number of other research groups built similar detectors and improved them better and better and better uh over that period of time on that model on that model the model so so I mean I

have enormous uh respect for for what he did sure now you now you decided to you and others uh decided to look differently for them so Ray Weiss Riner Weiss Ray his friends call him at MIT was the primary inventor of an alternative technique that was the technique that ultimately succeeded uh he invented it he wrote he wrote a a technical paper about the technique that identified all the noise kinds of noise that you would have to deal with and explained how you how you might deal with them and did an analysis of how good

this detector could be and he put there there's the recipe paper so oh my gosh it was a recipe for for how to go forward and he he wrote this in 1972 and Ry being Ry didn't publish this because he I think he figured you don't publish until you have built one and seen a gravitational way so but however Ray sent copies of this around all his colleagues and uh he put it into quarterly reports of the MIT laboratory in which he worked and so it it is probably the most influential non-published paper certainly that

I know of in physics I mean it was it was a t to force and it triggered uh the huge effort that that actually succeeded I was fortunate enough to to visit uh the cuz there were two Lego experiments one in Louisiana and the other one is in Hanford Washington why do you have two because you can't just have one result yeah they you're looking for a an effect that is so small that you wouldn't believe it unless you see it on two independent instruments there you go so you've got these pathways are they kilometer

long 4 km 4 km long evacuated you send a beam of light that is split from a sink beam laser that split it goes to these are at 90° angles and they go to the end they get reflected back and you rejoin them and you want to see if their waves line up and if they line up then each direction is identical you can go home if they're slightly different then one of these legs experienced a different encounter with the fabric of the SpaceTime Continuum than the other did so that's that's you know that's so

actually what you want to do is you make them slightly different in the first place but then so that means you send you send your laser light in from this direction uh there's a beam splitter where the light gets split in two to go down the two arms uh so laser G goes in like that there's this beam splitter so it the light gets split in two into one arm in that direction the other arm in this direction uh and uh then it comes back and recombines in the beam splitter the laser light was coming

in from this direction uh uh but when it recombines a little bit of light goes out uh in a perpendicular Direction so you have a laser here and you have an output over there and the out put direction is the direction that has a signal and if the if the length of one arm is shortened and the length of the other arm is in length and that would only happen because a gravitational wave washed over that arm that's right then you get a change in how much light is coming out to the output all right

so this you're trying to find a a change a length difference and if I remember the materials from the press releases that is equivalent to10th the diameter of a proton no it's equivalent to uh it's 10 million times smaller than an atom and 100 times smaller than a proton 100th this the diameter of a proton meanwhile all the world is vibrating because everything is at a temperature and and cool it as much as you want there's still vibrations and and and somebody is walking down the street I I remember being on campus there can I

call it a campus that's what it was and you can you can detect cars on the road a mile away you have to insulate this that's half the science done for the experiment you should get a Nobel Prize for that well that's that's what that's what the Nobel Prize was given for for that yeah to have successful isolated the effect you're trying to measure so so the way I like to describe it is you're trying to you're bouncing light off these mirrors and you're looking for a motion of the mirrors that is 10 million times

smaller than the atoms of which the mirrors are made and uh well the mirrors the atoms in the mirrors themselves are vibrating because they're at finite temperature by an amount that is about the same as their size so that million times smaller than uh the atoms and 10 million times smaller than the uh vibrations the atoms are undergoing so once again in physics there's a phenomenon we're trying to measure but it's kind of buried and you need a way to get to it and it seems like half if not more than half of the effort

is how brilliant is your engineer that you've brought on to the task to accompl accomplish this how good are your tools it's not just the idea it's now you got to make the damn measurement and it's not obvious you need very talented people assembled for this absolutely and so that was the issue is how good a team can you put together uh so when I learned of Ray Weiss's idea and I saw and I knew roughly how strong the strongest gravitational waves be I knew already then that uh it would be necessary to this would

be the Collision of two black holes of two black Hol and you can't just summon that up there has to be real things in the universe that might produce that right right you can't just wish for but based on what we knew about the universe at the time I was estimating a wave strength that was roughly correct and it was at that level that you would have to monitor the motion of these mirrors at 10 million times smaller than the atams in the mirrors and I thought to myself that's crazy and so in this book

which was published in 1973 we went to press just after Ray Weiss wrote his seminal paper I had not yet uh really studied that paper fully uh but I I just knew uh that this was crazy and so it describes in a few words Ray's idea in here and then it says I think there's an exercise where it says show why this is not very promising just a mild gentle because it is a textbook right you get to you get to declare that the students students challenge to show well it could not be a very

good idea in 1973 but fast forward a half a century right so so it is 1850 flying is not a good idea right on why flying isn't a good idea yeah but so but that was the central issue if if we worked for a few decades did we have a shot at success in 1973 I thought no no way but by 1975 I had turned around I'd had long conversations with Rey I'd had long conversations with Vladimir binsky a colleague in Moscow i' done lots of calculations of my own and I came to the conclusion

that you had had a real shot at success if you put together a superbly strong team and you worked at it for a few decades and you need money and you you were well supported I think by the National Science Foundation well not yet so at that point and NSF had given Rey $60,000 to get started and uh $6,000 that's that that's how much he had in the 1970s from the National Science Foundation he also had some money from the Air Force office of scientific research I'm not sure how much he had or he had

had that until until in the Vietnam era they stopped supporting science uh due to something called the Mansfield Amendment American politics and that's when NSF picked him up and gave him 60,000 that was a drop in the bucket compared what was needed and n St wasn't about ready to put big money in this required some members of your team to like appear in front of Congress to defend this that's that's that's correct and uh and uh but that was much later the issue was getting started and so how did we get started Caltech is a

very different kind of an institution than any other I've ever dealt with Caltech I was able to say to propose to my colleagues that we get into this field that we uh uh build a experimental program in parallel with Ray Weiss's program at MIT so my co the chair of the division of physics mathematics and astronomy at Caltech set up a committee to look at it committee uh looked at it for about six months detailed study came back and enthusiastic said let's go ahead and so Caltech put private money about $2 million of its own

private money to get started and uh that inflates about $12 million today oh of private money when when nobody else is putting anything in not you're right that's a very different CL a very different culture at Caltech as you describ that had happened and we had brought Ron dver from Scotland to start the experimental effort then NSF and NSF stood up and took notice they did their own study of this and came up with the same conclusion and they started funding us us and Ray Weiss and it became a Caltech MIT collaboration let's fast forward

to 2016 uh where you make the first detection announc it in 16 you announced it in 16 by the way I would later learn that when I visited the facility in Louisiana you already had made the detection and You' be happy to know that everyone was completely zip mouthed about until it was officially because I I I have this huge like internet following right and people were totally zip mouthed I swear I didn't know about it until the press release came yeah we we were all sworn the secret yes yes and so the the confirmation

of a first detection came from the second facility built in Hanford and at that point you have a time delay because gravitational waves move at the speed of light correct so and Earth is a finite size and so all that worked out yeah yeah so it was just seven milliseconds 7 a second time difference because the waves came up from the south they entered the Earth around the tip of the Antarctic Peninsula traveled through the Earth came up through the Earth at in Louisiana first and then Washington State second 7 milliseconds later this is and

and then the waves were unaffected by all the matter of the earth they just they and they couldn't see the difference between Earth and no Earth and they couldn't see the difference between detector and no detector they were very hard to do and their thing so what impresses me greatly is here we have a prediction made by Albert Einstein when in in 1916 or 15 whatever Albert Einstein in a little known fact I mean physicists know but I don't think the public knows Einstein laid out the equations for the stimulated emission of radiation which is

the physical Foundation of a laser yeah that's he he wrote that down first Y and a laser would take a few decades to actually be built into the 1950s and I'm just saying here's Einstein predicting gravitational waves laying the foundation for a laser and a hundred years later his gravitational waves are found with lasers yes so these are crumbs spilling off his plate Einstein was kind of smart and lo and behold nobody surprised the Nobel Prize goes to this project um and you along with Ray Weiss and Barry barish uh share the Nobel Prize what

year was that oh 2017 yeah so they apologized to us they didn't give us in6 because uh we didn't announce it until uh past their deadline for well plus they delay anyway they never no they they said obviously it was obvious the prize was going for this just obvious yeah hey Star Talk fans I don't know if you know this but the audio version of the podcast actually posts a week in advance of the video version and you can get that in Spotify and apple podcast and most other podcast Outlets that are out there multiple

ways to ingest all that is Cosmic on Star Talk you can't be a gent relativity Einstein guy without being a black hole guy so uh forgive me for asking you to retell a story you've probably told a thousand times but there's some famous bet you made was it with presal with some other physicist pral and and Hawking and Steph Hawking uh by the way I was was at the University of Texas when presc was there I think he was like a postto or some he was some it was just starting out that's how old I

am I'm an old guy I'm an old guy you're you're a young kid I'm an old man uh so uh you made a bet and let me see if I can set the table here a black hole once we all agree that they exist we can ask other questions when you have something outside the black hole and it falls in what happens to that information that was contained in that object is it gone forever and is that okay uh because information theory was a whole branch of science shall I call it science that was rising

up at around the same time and and entropy um became a a buzzword among many so what was the BET and how did it and how was it ultimately resolved the BET was between Stephen Hawking and me on one side John presal on the other side it was over whether or not information does get lost in black holes the background of and why is that so bad okay so it's it's it's bad because uh the fundamental laws of quantum mechanics as they are normally formulated physicists are widely agreed that quantum physics is fundamental uh and

that quantum physics underlies all of physics it's the most successful Theory ever put forth right and of the universe and classical physics where there are not these Quantum fluctuations there are not these probabilities that arises from quantum physics as an approximation under ordinary everyday circumstances there are many people who caricature science physics in particular by saying well we used to think classical physics was it but now we discard it in of quantum physics but that's not true no quantum physics absorbed yeah as well as relativity general relativity absorbing Newtonian gravity yeah it doesn't it's not

discarded it's a bigger understanding a deeper understanding okay just want to emphasize that many people get that confused and so quantum physics is normally formulated is UN is almost universally uh viewed has built right into it from the very beginning a the fact that information cannot be lost now these words information cannot be lost are a translation into everyday language of something else which is not everyday language which says that uh the evolution of everything in the universe is unitary and so those those are buzzwords that are not part of the normal lexicon but I

want to to say just to say that be indicate that there's some very very extremely precise version of this of which information is being lost is a colloquial way of saying it okay okay but it represent a violation of some fundamental tenets of quantum theory that's right Stephen Hawking back when he was visiting Caltech who by the way we've interviewed for Star Talk in our iives check it out in 19747 7475 he spent a year in my research group at Caltech we were very close friends and uh he during that period he having discovered something

called Hawking radiation which uh is a a very slow evaporation of a black hole it emits radiation slowly evaporates uh he then while he was here uh began to look much more deeply at quantum theory in black holes and he came up with a prediction that information really is lost and when black holes evaporate you could form a black hole uh it if you waited long enough much longer than the age of the universe for normal black holes uh the black hole would evaporate and all the information that went into the black hole would be

gone the black hole would be gone you just simply lost the information that no longer longer is there and that was complete violation of the normal tenants of quantum mechanics and yet he was claiming that was true he he wrote a paper on this with all the technical details he couldn't get it published because it was it was so obvious it had to be wrong but nobody could see anything wrong in his calculation and so he had to fight for more than a year to get it published if you look at this P public paper

you see the submission date as all research papers give you yes they give you a submission date and then you usually have a revised date and then it's published there's no revised date there's a submission date and the publication date is something like nearly a year and a half later he fought for for a whole year more than a year to get this thing published and physicists struggled with this ever since uh so uh those of us whose root are in relativity tended to believe Hawking and those of us whose Roots were in who grew

up with quantum mechanics instead of Relativity first those of us who were enamored of Relativity tended to believe Hawk and so Hawking and I made this bet with presal whose Roots were in uh in in quantum physics and he's the junior of you both right young whippersnapper coming up he is he is now the Richard P fer professor profor of thetical physics at calch I'm the Richard P fan physic professor of thecal physics Emeritus Emeritus okay I'm young whipper snappers oh man they'll take your job in a minute so I just turned the chair over

to to Johan I mean John is brilliant he's a hell of a lot smarter than I am hell of a lot smarter anyway so so we made this bet and uh this was in a period when Hawking was starting to visit Caltech for Ally 3 to six weeks every year was he yet wheelchair bound oh yeah he'd been wheel he was wheelchair bound uh going way back to about 1970 okay and uh this is 1990 oh W much later okay we made the BET around 1990 so the stage is set okay the cage match is

set you and Stephen Hawking Titans in your field in your subject conclude yeah information is lost especially if Hawking radiation you can evaporate the black hole and everything is gone there's no there's no memory of what was there ccll is declaring that information is not lost and his roots are deep in quantum physics which we know has never been shown to be wrong and they're both smarter than I am and they both know a lot more about quantum physics than I do because we'll return to this but let me just explain that through my whole

career I've thought that the quantum gravity come combining general relativity with quantum physics was the most important area of physics of all but I also made a decision when I was very young I will never work in quantum gravity because the field is too crowded there too many smart people there I I will I will pick I'm smart enough to pick really important problems that I can solve uh that nobody else is working on and and they'll only they'll only figure out later that I'm right that that those problems are important but I won't touch

a problem a problem wherever we got a million people in the room there too too many smart too many smart people in the room so anyway so so they they have now agreed that information is not lost so Hawking conceited and and by association with you or or have you still a hold out on this no I'm still a hold out okay and then and and and what led to this concession if I understand correctly so he Stephen together with a St was working on a a idea for how the information might be uh recovered

and he basically said that in quantum physics if you form a black hole and then it evaporates there's also it's a tiny probability that the black hole never formed in the first place and the information sneaks out through the root where it didn't form in the first place and uh and I'm sorry that sounds like a cop out yeah well it does sound like a cop out but it's it's very it's very clever and it's in keeping with how physics works but it's not obvious that it's right but it's it's conceivable this is this is

this is what about the idea so maybe I've misunderstood so I got to go back to see where I've said this even publicly I thought as the black black hole evaporates cuz the energy the gravitational energy in the vicinity of a black hole and spontaneously make a pair of particles and one particle escapes the other one falls into the black hole and this just keeps going until there's no black hole left but the particle that escapes if you inventory those particles they're real particles and don't you recover all the particles that went in in the

first place oh you recover all the energy but they don't but not the inventory of particles the don't get the same particles necessarily how okay then I misunderstood that I I've been wrong I think I've been wrong I thought you get particle for particle they come out which blew my mind uh I don't think there certainly there's no proof that that's the case well of course we we certainly no proof that the case I don't and I don't and I don't think it is the case okay okay but okay so so you guys lost the

bat well no I okay Hawking concedes the bat Hawking concedes the bat and what was that stake for this the loser will give the winner an encyclopedia filled with information that that somehow escaped the black hole and so and so so information is the penalty gift that's right so they Stephen Hawking conceded the V at an big International Conference on general relativity and gravitation in Dublin Ireland uh and early 2000 were there gasps in the audience there R were rumors that he was going to concede and so there was a big ceremony that uh I

played some role in the ceremony but I didn't concede myself uh and uh and so Stephen gave presc was a big baseball fan Encyclopedia of American baseball oh any kind of Encyclopedia okay well that was his idea that's that's clever so anyway so and less expensive yeah I didn't concede for a peculiar reason that uh there is an alternative formulation of Quant mechanics in which uh information could be lost it's due to Fineman called a sum over histories formulation and uh I as I say I don't work in quantum theory in any deep sort of

way I do in terms of quantum technology which I we needed for ligo but that's a separate story but uh two of the very deepest physicists in uh in uh working in quantum theory of of my lifetime uh were Murray galman and Jim hardle Jim harle at Santa Barbara gmon at calch and then he moved to the Santa Fe Institute to and retirement gilm man is credited with proposing quarks as the fundamental article of science of thecal physics when I was a young physicist ptech were galmon and feineman and two colleagues of mine that I

enormously respect uh so Gman and hardle took fineman's path enderal or some of History's approach to quantum mechanics and they developed it further and a form that they could apply it to cosmology to the universe and uh then uh they hard has used that to study Quantum cosmology the quantum mechanical description of how the birth of the universe and how it has evolved that particular approach to Quantum Mechanics hardle took it and he showed how uh that approach can deal perfectly well with information loss and uh and it deals with it it arises because of

what we call closed timel curves there's a certain probability for backward time travel in Quantum in quantum physics and in in this the in this Fineman galman hardle approach uh there's a certain probability for backward time travel and if you can have backward time travel uh at the quantum level then you lose information and there's so there elegant mathematical uh formulation Quant physics is so weasly this way well that's that that's not the standard version of quantum mechanics but that was the version that that that fan and that hardland Gman needed in order to do

the quantum mechanics of the entire universe and the birth of the universe so we're getting into this issue of the birth of the universe and and and Quantum quantum gravity here and and and I am rather enamored of this approach although I don't do it I just look on the sidelines and admire the these people who are smarter than I am and who have the courage to work in a crowded field but but I'm just so impressed with this uh and with the fact that within that formulation you can lose information is that the start

of a formulation that will one day marry general relativity in quantum physics well it it it does do that it's it's not it's not I it's knocking on the door it's knocking on the door it's it's it's it's it's and so so remind me now your professor thorn in this question what is the problem with G relativity not melding together with quantum physics what is the what is the real holdup there well the real holdup is that they are logically incompatible with each other and so something has to give and that's because of the qu

general relativity requires space to be a continuous you have a Continuum space you and and it's a very definite space it's not a space where you have a certain probability that space is Warped in this way and another probability is Warped in that that way in fact there no probabilities at all yeah there are classical probabilities but not Quantum not Quantum probabilities and so at the at the smallest scale they're incompatible the smallest scale they're incompatible in in any place where gravity becomes extremely strong they're incompatible so the the smallest scale they're incompatible uh even

here in this room but also they're incompatible they're incompatible in the birth of the universe When Gravity was extremely strong they're incompatible in the cord of a black hole where gravity is extremely strong they're incompatible uh if you try to make a time machine hockey and I independently with our students s of identified a process whereby if a very Advanced civilization tries to make a time machine it will quite possibly explode at the moment you try to turn it on uh and that's also controlled by uh these laws of quantum gravity so that's why we

haven't seen any time travelers yet oh that's that's that may be the explain Dead trying to turn on the machine that's right what you're saying is Einstein puts forth the general theory of relativity which is so successful in so many Realms and it picked up where Newtonian gravity failed yet we must confess or concede that there's a limit to how far general relativity goes although we've yet to find a limit to quantum physics so the betting the betting pool will say general relativity is going to succumb to quantum physics in some way yeah that that's

one way to say it they certainly there is the incompatibility between the two and strength theorists are trying to be this they're like performing the shotgun wedding between the two branches of physics somehow yeah and I I do think again looking in from the outside since I've chosen not to work in this field that string theory is uh is likely to be a successful route into the correct loss of they've been add it for 50 years0 40 years very long come on I I'm 84 years old come on that's that's that's just a drop in

the bucket come on wait but Einstein went from special relativity to general relativity in 10 years Kepler went from from weird nested solids to the Kepler's Three Laws of Motion in 10 years and that's lone scientists we've been working to try to do controlled Fusion for longer than more than 50 years ligo took 50 years from the time I first started working on gravitational waves until we succeeded it was 50 years some things take a long time yeah but ligo is a machine the the merging of quantum physics and general relativity are ideas could it

be and I've said this I I I I don't want to say this to you because you're you're Kip Thorn but but I've said this to Brian Green okay because Brian Green's like my generation I said to Brian Green I said Brian you've been working on strength theory for decades uh maybe all of you are just too stupid to figure it out and we're waiting for someone else to be born into this field to then solve it in the ways none of the rest of you can none of them are saying I'm too stupid to

figure this out let me choose another profession no they're saying the problem is too hard and if you go 40 Years of really smart people not figuring something out that tells me either they're barking up the wrong tree or none of them are smart enough am I am I overreacting I I I think you have to remember that we do build on each other none of them by themselves are smart enough okay but the the community again it's it's like this Nobel Prize really belongs to a thousand people doesn't belong to me uh it with

a Genesis in and in Joe Weber a Genesis and Joe Weber we build NE Newton spoke of standing on the shoulders of giants and that really is true the if I can see farther than others it's because I've stood on the shoulders of giants who' have come before me and that's the nature of science and the uh struggles that our colleagues have been having with string theory and M Theory and quantum gravity we learned an an enormous amount uh it shows it's very promising uh but it's going to continue on into the Next Generation before

the ultimate successes had a very very very probably those are like final words right there those are K I've heard rumor that whichever faculty of Caltech gets a Nobel Prize they get a parking spot with their name on it is that true if I went at calch a Nobel Prize does not get you a parking spot with your name on it you have you you have to pay for this parking spot just as much as you do without a Nobel Prize okay that was such a fun rumor though I heard that that that's true at

USC but it's not true at Caltech okay because there's just too many of you all running around with Nobel prizes then the parking spots are too valuable so chew it USC okay just chew it USC all right so you're 84 you have 84 years of wisdom hsing in your veins and arteries are there any projects you're working on in the next several years no I I made a gradual transition conscious uh away from science away from scientific research uh beginning uh around 15 years ago oh I you know I would like to be like to

believe I can live to 110 that's my uh intended goal uh and so for the uh next uh uh remaining decades I wanted to do things that I really enjoyed and I have enjoyed science I've been a conventional Caltech Professor for half a century uh enormously enjoyed it enormously enjoyed working with students I trained a over 50 PhD students and who did far more important research than I did uh and uh been there done that uh and I I have worked in all these areas of Science and I've had enormous fun but I've turned them

over to the younger generation and uh they're smarter than I am okay so what are you you you surfing now or or skydiving what okay you taking up other so so I I decided that I would like to spend a few decades uh doing creative work at the interface between science and the Arts oh so Interstellar is an example that was going to be released in September and then they delayed it to the holiday season in December so the re-release of re-release to December 2024 that's right that's right that that was enormously enjoyable I it

I from me I learned how great it can be to collaborate with somebody is brilliant and is completely different than I am Christopher Nolan so my most recent collaboration has been a book of poetry and paintings with Leah howerin uh and uh about the Warped side of the universe and uh my poetry my attempts at poetry and her paintings but just trying to see whether it's possible by tightly integrating paintings with a verse to convey the essence of issues in science the spirit the ENT essential features without conveying the precise details no that's not the

right genre for precise details but the anyway so I've been enjoying that by the way I've always felt that way about bango's Starry Night yes where you look at that painting you say this is clearly not what he saw but it's definitely what he felt yes yes and you get to experience the universe through his own lens yes and so I've always appreciated art when it plays that role yeah I have a second movie that's been in the works for more than a decade can you tell can you well it's just something that I started

with stepen Hawk and Linda opst who is my my partner on uh starting Interstellar uh and is wonderful to work with uh but that movie might might never get made I'm not going to tell you what it's about aside from the fact that it's sci-fi and it's solid sci-fi as high it's buil in from the outset so if that does not work out in the end uh then I may turn it into try turning it into a novel I've never tried to write a novel I whether I can but it would be fun to try

and actually the thing that I have put almost a large fraction of my effort in the Lion Share of my effort in since the beginning of the pandemic is a history of the ligo project the ligo gravitational wave project because that is I think pretty clearly the technically most difficult uh thing that's ever been done by physicist by anybody uh by anybody yeah probably by anybody and 11 100th the diameter of proton that's anybody and and uh success required both uh amazing developing amazing technology new technologies it required developing uh computer simulations of colliding black

holes required developing Quantum Precision measurement technology that is now in ligo and is playing a major role where you circumvent the What's called the Heisenberg uncertainty principle my mind is still partly blown by having by you having said that you're bypassing Heisenberg's uncertainty princi that's right you by manipulating vacuum fluctuations just like Advanced civilizations might do as a routine thing yeah so we had to we developed this new area of technology for Lio uh the and but it was also a very political thing how do you get a billion dollars of taxpayer money uh for

a field that doesn't didn't exist when you began and should they bet on you and not someone else right and plus I think you even had naysayers if I remember correctly colleagues would say this is a this is a pipe we we had we had political battles in Washington yeah tell me who the Nays saers were I got people take care of they were some of the leading astronomers in I got people take you want my people to no they they've come around you think okay they've come around because this this is so exciting now

now that Lego succeeded but but the sociology of the transition from small science to big science is a very Rocky process and that's the right word sociology because that's what it is I I don't like working in a big Pro big science project it's not for me just like working in a crowded field is not for me but we had to tr we this had to make the it wouldn't have happened transation wouldn't have happened otherwise the genius of Barry beish in in making that happen was and the genius of Robie voked and getting us

partway there the very beginning is our initial director who was the one that sold it to Congress and and uh and it really got us going it's it's a very complicated story and I have a a set of five collaborators I've been working on with this history we just finished draft six and sent it out to Liu colleagues to comment on and I have getting back huge numbers of comments and it'll take me two more years I think to so anyway the this this history because of the nature of this project it's a very interesting

and complex history that is quite important for the F for the history of science ESP when you consider most people knew nothing of Lio until they see the headline that it discovered gravitational and why would they have any thought of what challenges preceded that you know they just read the result oh scientists discover this well how about the the the like you said the politics the sociology the the Genesis the who's standing on Whose shoulders who the naysayers all that has to be overcome the international collaboration key input from the Soviet Union in the depths

of the Cold War and I me it's it's just a fascinating story and enormous fun you know Arthur C Clark said he said um in space where there is no air a flag will not wave so maybe the universe is not a place where we should be waving flags collaboration is what gets you there I like that so Kip this has been a delight thanks for making time a lot of fun first star talk I look forward to uh the release of the re-release of interstellar uh we're recording this before that has come out and

uh you already know this but let me reaffirm that that film just took people on a ride uh far beyond anything they had imagined they had kind of an impact on people in the way 2001 Space Odyssey did it was it was mysterious it was Modern it was the future but was still relevant but it left you with more questions to ask than questions answered and and that you want that I think yeah and and that was really The Genius of Christopher Nolan uh taking some science that he and I had put together together but

combining with a human story that it was powerful uh and uh and with Marquee director and Marquee actors that made sure would get noticed music yes uh I went to a concert by hun Zimmer who just I think the night before last and uh he let loose what I didn't know there that he basically said that the mus certain pieces of the music in interstellar are as close to Perfection as he has achieved wow I'm going to give it another listen because there is no 2001 without its musical track with the Strauss Wales the the

this is very different it's all all Zimmer's original music and it's a a remarkable score uh just amazing i' look forward to your next 25 years when you live to0 uh maybe we can do a reprise of this conversation we'll check in on you see how you've been coming along dude okay thanks a lot thanks great to see you again thanks this has been a special conversation exclusive one-on one between Star Talk and hip Thorn Nobel laurate even let me touch his metal first time I've ever touched the Nobel Prize well the medal that really

belongs to a thousand the medal earned by a huge team as he uh humbly declares and as we enter a new era of science where collaborations are really how this works especially where you have international collaborations you have scientists getting along even at times when the leaders of their countries are in Conflict that's just messed up that's that's messed up I'm Neil degrass Tyson your personal astrophysicist for Star talk as always I bid you to keep looking up [Music] [Music] [Music] [Music]