Barry Barish: Gravitational Waves and the Most Precise Device Ever Built | Lex Fridman Podcast #213

the following is a conversation with. barry barish a theoretical physicist at. caltech and the winner of the nobel. prize in physics for his contributions. to the ligo detector and the observation. of gravitational waves. ligo or the laser interferometer. gravitational wave observatory is. probably the most precise measurement. device ever built. by humans. it consists of two detectors with four. kilometer long vacuum chambers situated.

three thousand kilometers apart. operating in unison to measure a motion. that is ten thousand times smaller than. the width of a proton. it is the smallest measurement ever. attempted by science a measurement of. gravitational waves caused by the most. violent and cataclysmic events in the. universe. occurring over tens of millions of light. years away. to support this podcast please check out. our sponsors in the description.

this is the lex friedman podcast and. here is my conversation with barry. barish. you've mentioned that you were always. curious about the physical world and. that an early question you remember. stood out where you asked your dad. why does ice float on water and he. couldn't answer and this was very. surprising to you. so you went on to learn why. maybe you can speak to what are some. early questions in math and physics that. really sparked your curiosity yeah.

that memory is. kind of something i used to illustrate. something i think that's common in. science that people that do science. somehow have maintained. maintain something that kids always have. a small kid. eight years old or so. asks you so many questions usually. typically that you. consider them pests you tell them to.

stop asking so many questions. and. somehow our system manages to kill that. in most people. so in school we make people do study and. do their things but not to pester them. by asking too many questions. and. i think. not just myself but i think it's typical. of scientists like myself that uh. have somehow escaped that maybe we're. still children or maybe we.

somehow didn't get it beaten out of us. but. i think it's i teach in a college level. and it's to me. one of the biggest deficits is the lack. of curiosity if you want that we've. beaten out of them because i think it's. an innate human quality is there some. advice or insights you can give to how. to keep that flame of character i think. it's a problem of both parents and. and. the parents should be should realize. that's a great quality we have. that you're curious and that's good.

instead we have we have expressions like. curiosity killed the cat. and. and uh. and more but i mean that basically it's. not not thought to be a good thing you. get curiosity killed the cat means if. you're too curious you get in trouble. and i don't like catholics anyway so. maybe it's a good thing yeah yeah. that to me needs to be solved really in. education and in homes it's a. realization that there's certain human. qualities that we should try to build on.

and not destroy one of them is curiosity. anyway back to me in curiosity i was. passed and asked a lot of questions my. father generally could answer them. and at that age. and the first one i remember that he. couldn't answer. was. not a very original question but. basically that. ice is made out of water and so why does. it float on water. and.

he couldn't answer it. and it may not have been the first. question it's the first one that i. remember and and that was the first time. that i realized that. to learn and answer your own curiosity. or questions there's various mechanisms. in this case it was going to the library. and. or asking people who know more and so. forth but. eventually you do it by what we call. research. but but it's um.

driven by. if you're. hopefully you ask good questions if you. ask good questions and you have the. mechanism to solve them then you do what. i do in life basically not necessarily. physics but. and it's a great quality in humans and. we should nurture it. do you remember any other kind of in. high school maybe early college. more basic physics ideas. that sparked your curiosity or. mathematics or science engineering i. wasn't really into science.

until i got to college to be honest with. you. but. just staying with water for a minute i. remember. that i. was curious. uh. why uh what happens to water you know it. rains and there's water in a wet. pavement and then the pavement dries out. what happened to this. water that came down. and i you know i didn't know that much. and then eventually i learned in. chemistry or something water is made out. of hydrogen and oxygen those are both.

gases so how the heck does it make this. substance this liquid. [Laughter]. yeah so but so that has to do with. states of matter. you've uh i know. perhaps ligo and. the the thing for which you've gotten. the nobel prize and the things much of. your life work. perhaps was a happy accident in some. sense in the early days but is is there. a moment where you looked up to the. stars and also the same way you wondered. about water wandered about some of the.

things that are out there in the. universe. oh yeah i think everybody's. looks and. is in awe and is curious about. what what it is out there and you know. and as i learned. more i learned. of course that we don't know very much. about what's there and the more we learn. the more we know we don't know i mean we. don't know what the majority of anything. is out there it's all. what we call dark matter a dark energy. and that's one of the big questions 20.

year when i was a student those weren't. questions so we even know less in a. sense the more we. uh the more we look so. of course i think that's. one of the areas that. almost it's universal people see the sky. they see the stars and they're beautiful. and. and see it looks different on different. nights and it's a curiosity that we all. have. what are some questions about the. universe. that in the same way that you felt about.

the ice. that today. you mentioned to me offline you're. teaching um a course on the frontiers of. science frontiers of physics yeah what. are some questions. outside the ones we'll probably talk. about that kind of. yeah fill you with uh. get your flame of curiosity up and uh. firing up. yeah you know fill you with all. well first i'm a physicist not an. astronomer so i'm interested in physical.

the physical phenomenon really so. the question of of uh. dark matter and dark energy which we. probably won't talk about are rece or. recent their last 20 30 years or. certainly dark energy. dark energy is a complete puzzle. it goes against what i'll. will what you will ask me about which is. general relativity and einstein's. general relativity it basically takes. something that he thought was. what he what he called a constant which.

isn't and. and uh. in the if that's even the right theory. and it represents most of. the universe. and then we have something called dark. matter and there's good reason to. believe it might be an exotic form of. particles um and that is something i've. always. worked on on particle accelerators and. so forth and it's a big puzzle what it. is it's a bit of a cottage industry and. that there's. lots and lots of searches.

um but it may be a little bit like you. know looking for a treasure under rocks. or something you know it's hard to. we don't have really good guidance. except that. we have very very good. information that. it's pervasive and it's there. and that it's probably particles small. that the evidence is all of those things. but then the most. uh logical solution doesn't seem to work. something called supersymmetry.

and. do you think the answer could be. something very complicated. you know i like to hope that think that. most things. that appear complicated are actually. simple if you really understand them. i think we just don't know at the. present time and it isn't something that. affects us it does affect it affects how. the stars go around each other and so. forth because we detect that there's.

missing gravity but. uh but it doesn't affect. everyday life at all i tend to. think and. expect maybe and that the answers will. be simple we just haven't found it yet. do you think those answers might change. the way we see. other sources of gravity black holes. the way we see. the parts. of the universe that we do study it's. conceivable. the black holes that we've found in our.

experiment and now we're trying now to. understand the origin of those. it's. conceivable but not. doesn't seem the most likely that they. were pre-primordial that is they were. made at the beginning and they in that. sense they could represent at least part. of the dark matter. so there can be connections dark. black holes or. how many there are how much of the mass. they encompass is still pretty primitive. we don't know so before i talk to you. more about black holes let me take a.

step back to yeah i was actually went to. high school in chicago and would go to. uh take classes at fermi lab. uh watch the buffalo and so on yeah. so let me ask about you mentioned that. enrico for me was somebody who was. inspiring to you. in a certain kind of way um. why is that can you speak to that sure. he was amazing actually uh. he's the last. this is not the re i'll come to the.

reason in a minute but the. he had a big influence on me at a young. age. he uh but he was the only the last. physicist. of note. that was both an experimental physicist. and a theorist at the same time. and he did two amazing things within. months. in 1933. he. it was we didn't really know what the. nucleus was what uh. radioactive decay was what beta decay.

was when electrons come out of. a nucleus. and in. nearly near the end of 1933. um he. the neutron had just been discovered and. that meant that we knew a little bit. more about what the nucleus is that it's. made out of neutrons and protons the. neutron wasn't discovered till 1932. and then once we discovered that there. was a neutron and proton and they made. the nucleus and then their electrons.

would go around the basic ingredients. were there. and he uh wrote down not only just the. theory a theory but a theory that lasted. decades. and has only been. improved on. of beta decay that is the radio. radiation he did this. came out of nowhere and it was a. fantastic theory he submitted it to. nature. magazine which was the primary. play best place to publish even then.

and it got rejected as being too. speculative. and so he went. back to his. drawing board in rome where he was. added some to it made it even longer. because it's really a classic article. and then published it in. the local italian. journal for physics and the german one. at the same time in 19 january of 1932.

giulio and curie for the first time. steve saw artificial radioactivity. this was an important discovery because. radioactivity had been discovered much. earlier and you know we'd they had. x-rays and you shouldn't be. using them but they there was. radioactivity people knew it was useful. for medicine. but radioactive materials are hard to. find and so it wasn't prevalent but if. you could make them. then they had great use and julio and.

curie. were able to bombard. aluminum or something with alpha. particles and. find that they excited something that. decayed and gave. decayed and gate had some half-life and. so forth meaning it was artificial. version. or let's call it a not not a natural. version an induced version of. radioactive uh. materials. and uh. fermi.

somehow. had the insight. and i still can't see where he got it. that the right way to follow that up was. not using. charged particles like alphas and so. forth but use use these newly discovered. neutrons as the bombarding particle. seemed impossible they barely had been. seen. it was hard to get very many of them. but it had the advantage that they don't. um they're not charged so they go right.

into the. to the nucleus. and that turned out to be the. experimental work that he did that won. him the nobel prize. and it was the first step in fission. discovery of fission. and that's he did this two completely. different things an experiment that was. a great idea. and a. tremendous implementation because how do. you get enough neutrons. and then he learned. quickly that not only do you want.

neutrons but you want really slow ones. he learned that experimentally and he. learned how to make slow ones and then. they were able to make go through the. periodic table and make. lots of. particles he missed on fission at the. moment but he had the basic information. and and then fission followed soon after. that forgive me for not knowing but is. the birth of the idea of bombarding with. new uh. neutrons. is that uh.

is that an experimental idea was it born. out of an experiment you just observe. something or is this an einstein style. idea where you. took a combination because he realized. that neutrons had a characteristic that. would allow them to go all the way into. the nucleus when we didn't really. understand what the. you know what how what the structure was. of all this so that took. uh. an understanding or recognition of the.

physics itself of how a neutron. interacts compared to say an alpha. particle that giulio and curie had used. and then he had to invent. a way to have enough neutrons and uh you. know what he had a team of. associates and he pulled it off. quite quickly so you know it's pretty. astounding and probably maybe you can. speak to it. his ability to put together. the engineering aspects of great. experiments.

and doing the theory they probably fed. each other i wonder can you speak to why. we don't see more of that is that just. really difficult to do. it's difficult to do yeah i think in. in both theory and experiment in physics. anyway. was um. it was conceivable if you had an the. right person to do it and no one's been. able to do it since so i had the dream. that that. was what i was going to be like fermi. but so you love both sides of it the. theory yeah yeah i never liked the idea.

that you did experiments without really. understanding the theory or the theory. should be related very closely to. experiments. and so i've always done. experimental work that was closely. related to the theoretical ideas. i think i told you i'm russian so i'm. going to ask some romantic questions but. is it tragic to you that. he's seen as the architect of the. nuclear age that some of his creations. led to potentially. some of his work.

has has led to. potentially still the destruction of the. human species some of the most. destructive. weapons yeah. uh. but i think even more general than him i. i i gave you all the virtues of. curiosity a few minutes ago there's an. interesting book called the ratchet of. curiosity you know a ratchet is. something that goes in one direction. and that that it's written by a guy. who's probably a sociologist or. philosopher or something.

and he he picks on this particular. problem but other ones and that is the. the danger of knowledge basically you. know you're curious. you learn something so it's a little bit. like curiosity killed the cat you have. to be worried about whether you can. handle. new information that you get so in this. case the new information had to do with. really understanding nuclear physics. and that information maybe we didn't. have the sophistication to know how to. keep it under control.

yeah and fermi himself was. a very a political person so he wasn't. very driven by or or at least. he appears in all of his writing the. writing of his wife the interactions. that others had with him as either he. avoided it all or he was pretty. apolitical i mean he just saw the world. through kind of the lens of a scientist. but you asked if it's tragic uh. the bomb was tragic certainly on japan.

and he had a role in that so i wouldn't. want it as my legacy for example. i mean that but broader to the human. species that. it's the ratchet of curiosity that we. uh. we do stuff just to see what happens. that that curiosity that uh in sort of. my area of artificial intelligence. that's been a concern. they're on a small scale on a silly. scale perhaps currently there's.

constantly. unintended consequences you create a. system. and you put out there and you have. intuitions about how it will work you. have hopes how it will work but you put. it out there just to see what happens. yeah and uh in most cases because. artificial intelligence is currently not. super powerful it doesn't. create uh large-scale negative effects. but that same curiosity as it progresses. might lead to something that. destroys the human species and the same.

may be true for bioengineering there's. people. that. you know engineer viruses to protect us. from viruses. to see you know how do uh how close is. this to mutating so it can jump to. humans or going you know or engineering. uh defenses against those. and it seems exciting and the. application the positive applications. are really exciting at this time but. we don't think about.

how that runs away in decades to come. yeah and i think it's the same idea as. this little book the ratchet of. science the the. uh ratchet of curiosity i mean. whether you pursue take curiosity and. let. artificial intelligence or machine. learning run away with. having its. solutions to whatever you want or we do. it. it's i think a similar consequence. i think uh from what i've read about uh.

enrico for me he. he became a little bit cynical about the. human species towards the end of his. life. both having observed what he observed. we didn't write much. i mean he died young he died soon after. the world war uh. there was already you know. the. work by teller to develop the hydrogen. bomb and i think he was a little cynical. of that you know pushing it even further.

and. uh rising tensions between the soviet. union and the u.s and looked like an. endless thing so but he didn't say very. much but a little bit as you said yeah. there's a few clips to sort of uh maybe. picked on a bad mood but in in the sense. that uh almost like a sadness a. melancholy sadness to. um. a hope that waned a little bit about. that uh yeah perhaps we can do. like. the science this curious species can. find the way out.

well especially i think people who. worked like he did at los alamos and. spent years of their life. somehow had to convince themselves that. dropping these bombs would bring. lasting peace and it didn't and that it. didn't yeah. as a small interesting aside it'd be. interesting to hear if you have opinions. on this his name is also attached to the. fermi paradox which asks if there's uh. you know with.

it's a very interesting question which. is. if it does seem if you sort of reason. basically that there should be a lot of. alien civilizations out there if the. human species. if earth is not that unique. by. basic. no matter the values you pick. it's likely that there's a lot of alien. civilizations out there and if that's. the case. why have they. not at least obviously visited us or. sent us loud signals that everybody can. hear.

fermi's quoted as saying sitting down at. lunch i think it was with. teller. and uh herb york who was kind of the one. of the fathers of the atomic bomb. and he sat down and he says something. like where are they. yeah. which meant where are these. other and. um. and then he did some. numerology where he. calculated you know how many what they. knew about how many. uh.

galaxies there are and how many stars. and how many planets in are like the. earth and blah blah blah that's been. done much better by somebody named drake. and so people usually refer to the i. don't know whether it's called the drake. formula or something but it has the same. conclusion. the conclusion is it would be a miracle. if there weren't other. you know uh there's the statistics are. so high that how can we be singular and. separate. that so probably there is.

but there's. almost certainly life somewhere. maybe there was even life on mars a. while back but. uh. intelligent life. probably why were we so so you know the. statistics say that communicating with. us. i think that it's harder than people. think. we might. not know the right way to. expect the communication.

but all the communication that we know. about travels at the speed of light. and we do we don't we don't think. anything can go faster in the speed of. light that. limits the problem quite quite a bit and. it uh. makes it difficult to have any back and. forth communication you can send signals. like we try to or. look for but to have any communication. it's pretty hard when you it has to be. close enough that the speed of light. would mean we could communicate with.

each other and i think. and we didn't even understand that i. mean it's an advanced civilization but. we didn't even understand that. a little more than 100 years ago. so uh. are we. just not advanced enough maybe. uh to know something about that's the. speed of light maybe there's some other. way to communicate that isn't based on. electromagnetism i don't i don't know. gravity seems to be also this have the.

same speed that was a principle that. einstein had and something we've. measured actually. so is is it possible i mean so we'll. talk about gravitational waves and. it in some sense there's a. there's a brainstorming going on which. is like. how do we detect the signal like what. would a signal look like and how would. we detect and that's true for. gravitational waves that's true for. basically any physics phenomena. you have to predict that that signal. should exist you have to have some kind.

of theory and model why that signal. should exist i mean is it possible that. aliens are communicating with us via. gravity. like why not well it it. yeah it's true why not uh. for us it's very hard to detect these. gravitational effects they have to come. from something. pretty that has a lot of gravity like. black holes but we're pretty primitive. at this stage. there's uh.

very reputable physicists that look for. a fifth force. one that we haven't found yet maybe it's. the key so you know. it's what would that look like what. would a fifth force of physics look like. exactly well usually they think it's. probably a long range for longer range. force than we have now. um. but uh. they're reputable for colleagues of mine. that spend their life looking for a. fifth force so longer range than gravity.

yeah. super it doesn't fall off like one over. r squared but maybe. separately. gravity. uh newton taught us goes like inversely. one over the square of the distance. apart you are so it falls pretty fast. that's okay so now we have a theory of. what consciousness is it's just the. fifth force of. physics yeah there we go that's a good. hypothesis. uh. speaking of gravity uh of gravity uh. what are gravitational waves let's maybe.

start from the basics. we learned gravity from newton. right you you and you were young you. were told that if you jumped up the. earth pulled you down. and when the apple falls out of the tree. the earth pulls it down. and maybe you even asked your teacher. why but. most of us. accepted that that was newton's. picture the apple falling out of the. tree but newton's theory never told you.

why the apple was attracted to the earth. that was a missing in newton's theory. newton's theory also. newton recognized at least one of the. two problems i'll tell you one of them. is there's more than those but one is. why does the earth what's the mechanism. by which. the earth pulls the apple or holds the. moon when it goes around whatever it is. uh that's not explained by newton even. though he has the most successful theory. of physics ever went 200 and some years.

with nobody ever seeing. a violation but he accurately describes. the movement of an object falling down. to earth but he's not answering why that. what's yeah yeah because it's a distance. he gives a formula right which which. it's the product of the earth's mass the. apple's mass. inversely proportional to the square the. distance between and then the strength. he called capital g the strength he. couldn't determine but it was determined. 100 years later.

but no one ever saw a violation of this. until a possible violation which. einstein fixed which was very small that. has to do with mercury going around the. sun. the orbit being slightly. wrong if you calculated by. newton's theory. but so. um like most theories then in in physics. you can have a wonderful one like. newton's theory it isn't wrong. but you have to have a. an improvement on it to answer things.

that it can't answer and in this case. einstein's theory is the next step we. don't know if it's. anything like a final theory or even the. only way to formulate it. either. but he formulated this theory. which. which he. released in 1915. he took 10 years to develop but even. though in 1905 he solved three or four. of the most important problems in. physics in a matter of months and then.

he spent 10 years on this problem before. he. uh let it out and it's called general. relativity it's a new theory of gravity. 1915 in 1916. einstein. wrote a little paper. where he. did not do some fancy derivation instead. he did. what i would call it used his intuition. which he was very good at too.

and that is he noticed that if he formed. if he wrote the formulas for general. relativity in a particular way. they looked a lot like the formulas for. electricity and magnetism. being einstein he then took the leap. that electricity and magnetism we. discovered only 20 years before that in. the 1880s. have waves of course that's. light and electromagnetic rays radio. waves everything else so he said if the.

formulas look similar. then gravity probably has ways too. that's such a big leap by the way i mean. maybe you can correct me but that just. seems. so that seems like a heck of a look yeah. and so that and it was considered to be. a heck of a leap so first that paper was. except for this. intuition was. uh. poorly written had had a serious mistake. it had the a factor of two wrong and the.

strength of gravity which meant if we. use those formulas we would. and. two years later. he wrote a second paper. and in that paper it turns out to be. important for us because in that paper. he not only. fixed his factor of two mistake which he. never admitted he just wrote it fixed it. like he always did and. and then he. told us. how you make gravitational waves what. what makes gravitational waves.

and. you might recall in electromagnetism we. make electromagnetic waves in a simple. way you take a plus charge and minus. charge you oscillate like this and that. makes electromagnetic waves. and a physicist named hertz. made a receiver that could detect the. waves and put in the next room. he saw them and moved forward and. backward and saw that it was wave-like. so. einstein said it won't be a dipole like. that it'll be a four-pole thing and. that's what.

it's called a quadrupole moment that. gives the gravitational wave so he saw. that again by insight not by derivation. that's at the table for what you needed. to do to do it at the same time in the. same year schwartz child not einstein. said there were things like called black. holes so it's interesting that that came. the same so what year was that. 2015. it was in parallel. with i did. i should probably know this but did i.

say not have any intuition that there. should be such things as black holes. that came from schwarzschild oh. interesting. yeah. so schwartz child who was a. a german theoretical physicist he got. killed in the war i think in the first. world war a year two years later. or so. he's the one that proposed black holes. that there were black holes it feels. like a natural conclusion of uh general. relativity you know. or is that uh. [Music]. well it may seem like it but i don't.

know about a natural conclusion it is a. it's a result. of curved space time though right and. it's but it's such a weird result that. you might have to uh yeah it's a special. yeah it's a special case yeah. so um. i i don't know anyway. einstein then the interesting part of. the story is that einstein then left the. problem most physicists because it. really wasn't uh derived he just made. this. didn't pick up on it or general.

relativity much because quantum. mechanics became the thing in physics. and. einstein. uh. only picked up this problem again after. he immigrated to the u.s so he came to. the u.s in 1932. and i think in 1934-5. he was working with another physicist. called rosen who he did several. important works with and they revisited. the question. and they. had a problem that most of us as.

students always had that study general. relativity general relativity is really. hard because it's four-dimensional. instead of three-dimensional and if you. don't set it up right you get infinities. which don't belong there the we call. them coordinates singularities. as a name. but it but if you get these infinities. you don't get the answers you want and. he was trying to derive now general. relativity out from general relativity. gravitational waves and in doing it he.

kept getting these infinities. and so he wrote a paper with rosen that. he submitted to. our most important journal physical. review letters. and. that when it was submitted to physical. review letters it was entitled do. gravitational waves exist. a very funny title to write 20 years. after he proposed they exist. but it's because he had found these. singularities these infinities.

and so. the. editor at that time and the part of it. that i don't know. is peer review we live and die by peer. review as scientists send our stuff out. and it's we don't know when peer review. actually started. or what what peer review einstein ever. experienced before this time but the. editor of physical review sent this out. for review. he had a choice he could take any.

article and just accept it he could. reject it or he could send it for review. right i believe the editors used to have. much more power yeah yeah and he was a. young man his name was tate and he ended. up being an editor for years but. so he sent this for review. to. a theoretical physicist named robertson. who was also in this field of general. relativity who happened to be on. sabbatical at that moment at caltech. otherwise his institution was princeton.

where. einstein was. and he. saw that the way they set up the problem. the infinities were like i might get as. a student because if you don't set it up. right in general relativity you get. these. infinities. and so he reviewed the article and told. he gave an illustration that they set it. up in what are called cylindrical. coordinates these infinities went away. he's the. editor of. uh physical review was obviously.

intimidated by einstein he wrote this. really not not a letter back like i. would get saying you know you're screwed. up in your paper instead. it was kind of uh. what do you think of the comments of our. [Laughter]. referee einstein wrote back and it's a. well documented letter wrote back a. letter to physical review saying. i didn't send you the paper. to send it to one of your so-called. experts i sent it to you to publish.

i now i withdraw the paper. and he never published again in the in. that journal that was 1936 instead. he. rewrote it. with the fixes that were made changed. the title. and published it in what was called the. franklin review which is the. uh franklin institute in philadelphia uh. which is benjamin franklin institute. which doesn't have a journal now but. did at that time so the article is.

published it's the last time he ever. wrote about it. it remained controversial. so it wasn't until. close to 1960 1958 where there was a. conference in which brought that brought. together. the. experts in general relativity to try to. sort out whether there was uh. um. whether. it was true that there were. gravitational waves or not.

and there was a very nice. derivation by a british. theorist. from. the heart of the theory that gets. gravitational waves. uh and that was number one the second. thing that happened at that meeting is. richard feynman was there. and feynman. said well if there's a typical feynman. if there's gravitational waves they need. to be able to do something otherwise. they don't exist so they have to be able. to transfer energy so he made a.

idea of a gadonkan experiment that is. just a bar. with a couple rings on it. and then if a gravitational wave goes. through it distorts the bar. that creates friction on these little. rings. and that's heat and that's energy so. that that meant is that a good idea that. sounds like a good idea yeah it means. that he showed that. with the distortion of space-time you. could transfer energy just by this.

little idea and it was shown. theoretically so at that point. it was. believed theoretically then by. people that gravitational waves should. exist. no and we should be able to detect them. we should be able to detect them except. except that they're very very small. just so what kind of uh there's a bunch. of questions there but what kind of. events. would generate. gravitational waves you have to have. this what i call quadrupole moment that.

comes about if i have uh. for for example two objects that go. around each other like this like the. earth or the earth around the sun or the. moon around the earth or in our case it. turns out to be two black holes going. around each other like this so how's. that different than basic oscillation. back and forth this is just more common. in nature oscillation is a dipole moment. so it has to be in three-dimensional. space yeah kind of oscillations so you. have to have something that's. three-dimensional that'll give what's.

what i call the quadrupole moment that's. just built into this and luckily in. nature you have stuff. and luckily things exist. and it is luckily because the effect is. so small that you could say look i can. take a barbell. and. and spin it right and detect the. gravitational waves but unfortunately no. matter how much i spin it how fast i. spin it it's so i know how to make. gravitational waves but they're so weak. i can't detect them so we have to take. something that's stronger than i can.

make otherwise we would do what hertz. did for electromagnetic waves go in our. lab. take a barbell put it on something spin. it ask a dumb question so a uh a single. object that's weirdly shaped does that. generate gravitational waves so if it's. if it's rotating. sure. it it was just much weaker. it's weaker well we didn't know what the. strongest signal would be that we would. see. uh we targeted seeing something called. neutron stars actually because black.

holes we don't know very much about it. turned out we were a little bit lucky. there was a stronger source which was. the black holes well another ridiculous. question so. you say waves what is what does a wave. mean like. the most ridiculous version of that. question is what does it feel like. to uh ride a wave as you get closer to. the source. or experience it well if you experience. a wave imagine that this is what happens.

to you. i don't know what you mean about getting. close it comes to you so it's like it's. like uh this light wave or something. that comes through you so when the light. hits you it. makes your eyes detected. i flashed it what does this do is. it's like going to the amusement park. and they have these mirrors you look in. this mirror and you look short and fat. and the one next to you makes you tall. and thin. okay. imagine that you went back and forth.

between those two mirrors once a second. that would be a gravitational wave with. a period of once a second. uh if you did it 60 times a second go. back and forth and. and then that's all that happens it. makes you taller and shorter and fatter. back and forth as it goes through you. at the frequency of the gravitational. wave so. the frequencies that we detect are. higher than one a second but that's the. idea so but uh and the amount is small. amount is small but when if you're.

closer to the. to the source of the wave is it the same. amount. yeah it's it doesn't dissipate it. doesn't dissipate. okay so it's not that fun of an. amusement ride well it it does dissipate. but it doesn't it doesn't it's it's just. it's proportional to the distance right. it's not uh it's not a big power right. gotcha so but so. it would be a fun ride if you get a. little bit closer or a lot closer.

i mean like i i wonder what the. this is a ridiculous question but i have. you here. like the getting fatter and taller. i mean that experience. for some reason that's mind-blowing to. me. it brings. the distortion of space-time to you. i mean space-time is being morphed. right like this is a way right. that how that's so weird and we're in.

space so yeah we're in space and it's. moving. i don't know what to do with it i mean. does it okay um. how much do you think about the. philosophical implications of. general relativity like that we're in. space time. and it can be bent by gravity. like. is that just what it is are we are we. supposed to be okay with this. because like newton. even newton is a little weird right but. that at least like makes sense that's.

our physical world. you know when an apple falls it makes. sense. but like the fact that entirety of. the space time we're in can bend. well that's uh. that's i that's really mind-blowing. let me make another analogy this is a. therapy session for me at this point. right another analogy thank you so so. imagine you have a trampoline yes. okay. what happens if you put a marble on a.

trampoline it doesn't do anything right. no just saves a little bit but not much. yeah i mean just if i drop it it's not. going to go anywhere. now imagine i put a bowling ball at the. center of the trampoline. now. i come up to the trampoline and put a. marble on what happens. they'll roll towards the bowling ball. all right so what's happened is the. presence of this. massive object distorted the space. that the trampoline did.

this is the same thing that happens to. the presence of the earth. the earth and the apple the presence of. the earth affects the space around it. just like the. uh bowling ball on the trampoline yeah. this doesn't make me feel better i'm. referring from the perspective of an. aunt. walking around on that trampoline. then. some guy just dropped the ball and not. only dropped the ball right it's not. just dropping a bowling ball it's making. the the ball go up and down.

or doing some kind of oscillation thing. where it's like waves. and that's so fundamentally different. from the experience on being on flat. land and walking around and just finding. delicious sweet things as ant does and. just it just feels like to me from a. human experience perspective. completely it's humbling it's truly. humbling. it's something but we see that kind of. phenomenon all the time. let me give you another example imagine. that you walk up to a.

a still pond. yes okay. now i throw. it you like to throw you throw a rock in. it what happens. the rock goes in sinks to the bottom. fine and these little ripples go out. yeah and they travel. out that's exactly what happens i mean. there's a disturbance. which is the safe. the bowling ball or our black holes and. then the ripples that go out in the. water they're not they don't have any. they don't have the rock any part pieces.

of the rock i see the thing is i guess. what's not disturbing about that. is it's a i mean it's a i guess a flat. two-dimensional surface that's being. disturbed. like for a three-dimensional surface a. three-dimensional space to be disturbed. feels weird it's even worse it's. four-dimensional because it's space and. time yeah. so that's why you need einstein is to. make it uh. four-dimensional no.

to make it four-dimensional yeah yeah. it's gonna take the same phenomenon and. and. look at it in all of space and time. anyway luckily. for you and i and all of us. the amount of distortion is incredibly. small. so it turns out. that if you think of space. itself now this is going to blow your. mind too if you think of space as being. like a material like this table. it's very stiff you know we have.

materials that are very pliable. materials that are very stiff. so. space itself is very stiff. so when gravitational waves come through. it luckily for us it doesn't distort it. so much that it affects our ordinary. life very much. no i mean that's great. that's great i thought there was. something bad coming no this is great. that's great news so i mean that i mean. perhaps we evolved as the life on earth. do we. so to be such that for us this. particular set of uh effects of.

gravitational waves. uh is not that significant maybe maybe. that's why you probably used. this effect today. or yesterday. so it's it's pervasive well you mean. gravity or the way the external. because i only curvature of space. curvature of space how i only care. personally as a human right the gravity. of earth but you use it every day almost.

oh it's curving uh-huh no no no it's in. this thing. every time it tells you where you are. yeah. it how does it tell you where you are. it tells you where you are because we. have 24 satellites or some number that. are going around in space and it. asks how long it takes the. being. to go to the satellite and come back the. signal to different ones and then it. triangulates and tells you where you are. and then if you go down the road it. tells you where you are do you know that.

if you did that with the satellites and. you didn't use einstein's equations oh. no. you want it you won't get the right. answer that's right and. in fact if you take a road let's say 10. meters wide i've done these numbers and. you ask how long you'd stay on the road. if you didn't make the correction. for. general relativity this thing you're poo. pooing because you're using every day. uh you'd go off the road and you'd go. the middle road well actually that might. be so you use it so so well.

well i think i'm using an android so. maybe and the gps doesn't work that well. so maybe i'm using newton's physics uh. so i need to upgrade to general. relativity um so. gravitational waves and einstein. had uh wait fireman really does have a. part in the story was that one of the. first kind of experimental pro. proposed detect gravitation well he did. what we call a gadonkan experiment. that's a thought experience okay not a. real experiment but then after that. then people believe gravitational waves.

must exist you can kind of calculate how. big they are there's tiny. and so. people started searching the first idea. that was used was feynman's idea. and the. very end of it. and it was to take a great big. huge bar of aluminum. and then put around and it's a it's made. like a cylinder. and then put around it some very very. sensitive detectors so that if a. gravitational wave happened to go. through it it would go.

and you detect this extra strain that. was there and that was this method that. was used until we came along it wasn't a. very good method to use. and what was the. so we're talking about a pretty weak. signal here yeah that's why that method. didn't work so what can you tell the. story of figuring out what kind of. method would be able to detect. this very weak signal of gravitational. waves.

so. remembering the. remembering what happens if you when you. go to the amusement park yeah that it's. going to do something like. stretch this way and squash that way. squash this way and stretch this way we. do have an. instrument that can detect that kind of. thing. it's called an interferometer. and what it does. is it just basically takes usually light. and the two directions that we're. talking about you send light down one.

direction and the perpendicular. direction and if. nothing changes it takes the same and. the arms are the same length it just. goes down bounces back. and if you invert one compared to the. other they cancel so there's nothing. happens. but. if it's like the amusement park and one. of the arms got you know got shorter and. fatter so it took longer to go. horizontally than it did to go. vertically then when they come back when. when the. light comes back that comes back.

somewhat. out of time. and that basically is the scheme. the only problem is that that's not. a very done very accurately. in general and we had to do it extremely. accurately so what uh. what what's the what's the difficulty of. uh. doing so accurately okay. so the the measurement that we have to. do. is the distortion in time. how big is it one it's a distortion.

that's one part and 10 to the 21 that's. 21 zeros and a one. okay wow and this so this is like a. delay in the thing coming back. uh it's a one of them coming back after. the other one but the difference is just. one part and 10 to the 21. so for that reason we make it big. let it let the arms be long. okay so one part and 10 to the 21. in our case it's kilometers long so we.

have an instrument that kilometers in. one direction kilometers in the other. kilometers we're talking about four. kilometers four kilometers in each. direction. uh. if you take then one part and 10 to the. 21 we're talking about measuring. something to. 10 to the minus 18 meters. okay. now to tell you how small that is yeah. the proton yeah the thing we're made of.

that you can't go and grab so easily is. 10 to the minus 15 meters. so this is 1 1000 the size of a proton. that's the effect size of the effect. einstein himself didn't think this could. be measured have we ever seen. actually he said that. but that's because he didn't. you know anticipate modern lasers and. and techniques that we developed. okay. so. maybe can you tell me.

a little bit what you're referring to is. ligo the laser uh interferometer. gravitational wave observatory. what is ligo. can you just elaborate kind of the big. picture of you here before i ask you. specific questions about it yeah so. in the same idea that i just said we. have. two long vacuum. pipes. 10 to. 4 kilometers long okay. we start with a laser beam and we divide. the beam.

going down the two arms. and we have a mirror at the other end. reflects it back. it's more subtle but we bring it back. if there's. no distortion in space-time and the. lengths are exactly the same which we. calibrate them to be. then when it comes back if we just. invert one signal compared to the other. they'll just cancel. so we see nothing. okay. but if one arm got a little bit longer. than the other. then they don't come back at exactly the. same time they don't exactly cancel.

that's what we. measure. so. to give a number to it. we have to do that. to. we have. the change of length to be able to do. this 10 to the minus 18 meters to one. part in 10 to the 12th and that was the. big experimental challenge that. required a lot of innovation to be able. to do. what you gave a lot of credit to i think. caltech and mit for some of the.

technical developments like within this. project. is there some interesting things you can. speak to. like. at the low level of some cool stuff that. had to be solved like what are we yeah. i'm a software engineer so okay all of. this i have so much more respect for. everything done here than anything i've. ever done so it's just code so. so i'll give you. an example of doing uh. mechanical engineering.

and a better look at at a basically. mechanical engineering and geology and. maybe at a. level which. okay uh so what do we what's the problem. the problem is the following that i've. given you this picture of an instrument. that i by some magic i can make good. enough to measure this very short. distance. but then i put it down here. it won't work. and the reason it doesn't work is that. the earth itself is moving all over the. place all the time you don't realize it.

it seems pretty good to you i get it but. it's moving all the time so somehow. it's moving so much that you we can't. deal with it we happen to be trying to. do the experiment here on earth. but we can't deal with it so we have to. make the instrument. isolated from the earth. oh no. at the frequencies we're at we've got to. float it that's a mechanical that's an. engineering problem not a physics. problem so when you actually like uh. we're doing we're having a conversation. on a podcast right now there's uh and.

people who record music work with this. you know how to create an isolated room. and they usually build a room within a. room. but that's still not isolated in fact. they say it's impossible to truly. isolate from sound from noise and stuff. like that. but that that. that's like one step. of. millions that you took. is building a room inside a room because. you basically have to isolate all now. this is actually an easier problem you. just have to do it really well so the.

making a clean room is really a tough. problem because you have to put a room. inside a room yeah. so this is this is really simple. engineering or physics uh-huh okay so. what do you have to do how do you. isolate yourself from the from the earth. yes. first we work at. uh we're not looking at all frequencies. for gravitational waves we're looking at. particular frequencies. that you can deal with here on earth. so what frequencies would those be.

you were just talking about frequencies. i mean we know by evolution our bodies. know it's the audio band. okay the reason our ears work where they. work is that's where the earth isn't. going making too much noise okay so the. reason our ears work the way they work. is because this is where it's quiet. that's right. so if you go to if you go to one hertz. instead of 10 hertz. it's the earth is. it's really moving around so.

so somehow we live in a what we call the. audio band it's tens of hertz to. thousands of hertz that's where we. live that's where we live okay. if we're going to do an experiment on. the earth i might as well do this it's. the same frequency that's where the. earth is the quietest so we have to work. in that frequency so we're not looking. at all frequencies okay. so the solution for the for the shaking. of the earth to get rid of it. is pretty mundane if we do the same. thing.

that you do uh to make your car drive. smoothly down the road so what happens. when your car goes over a bump. early cars did that they bounced right. okay but you don't feel that in your car. so what happened to that energy you. can't just disappear energy so we have. these things called shock absorbers in. the car. what they do. is they absorb they take the the thing. that went like that and they basically. can't get rid of the energy but they. move it to very very low frequency.

so what you feel isn't. you feel like go shh. smoothly okay. all right so uh. we also work at this frequency so if we. so we basically why. why do we have to do anything other than. shock absorbers so we made. the world's fanciest shock absorbers. okay. not just like in your car where there's. one layer of them they're just the right. squishiness and so forth they're better.

than what's in the cars. and we have four layers of it so. whatever shakes and gets through the. first layer we treat it in a second. third. level so it's a mechanical engineering. problem yeah that's what i said so. it's not there's no weird tricks to it. like uh like a chemistry type thing or. no no just well the right squishiness. right need the right material inside and. ours look like little springs but. they're. springs they're springs so like. legitimately like shock absorbers yeah.

what. okay okay. and this is now experimental physics at. the at its limit okay so you do this and. we make the world's fanciest shock. absorbers just mechanical engineering. just mechanical genius is hilarious but. we didn't yes we weren't good enough to. discover gravitational waves. so. uh so we did another we added another. feature and it's something else that. you're uh. aware of probably have one.

and that is to get rid of noise you've. probably noise which is you don't like. and that's the same principle that's in. these little bose uh. uh earphones noise canceling. noise cancelling so. uh so how do they work they basically. you go on an airplane and they uh sense. the ambient noise from the engines. and cancel it because it's just the same. over and over again they cancel it and. when the stewardess comes and asks you.

whether you want coffee or a tea or a. drink or something you hear her fine. because she's not ambient she's a signal. so are we talking about active canceling. like where the action is canceling. so this is you okay so another don't. tell me you have active canceling uh on. this yeah besides the show absolutely. so inside this. array of shock absorbers yeah we you. asked for some interesting this is. awesome. so inside this it's harder than the.

earphone problem but it's just. engineering we have to see measure not. just that the. engine still made noise. but the earth is shaking it's moving in. some direction. so we have to actually tell not only. that there's noise and cancel it but. what direction it's from so we put this. array of seismometers inside. this array of shock absorbers and. measure the. residual. motion. and its.

direction and we put little actuators. that push back against it and cancel it. this is awesome. so you have the actuators and you have. the thing that is sensing the the. vibrations and then you have the actual. actuators that adjust for that and do so. in perfect synchrony yeah. what if it all works right and so how. much do we reduce the shaking of the. earth. i mean. one part in 10 to the 12th. part.

inside what gets through us is one part. and 10 to the 12th. that's pretty big reduction you don't. need that in your car but that's what we. do and so that's how isolated we are. from the earth and that was the biggest. uh. i'd say technical problem outside of the. physics instrument the interferometer. can ask you a a weird question here you. you make it very poetically and. humorously it's saying it's just a. mechanical engineering problem. but is this one of the.

biggest. precision. mechanical engineering efforts ever. i mean this seems exceptionally. difficult it is and so it took a long. time and uh i think. nobody seems to challenge the statement. that this is the most precision precise. instrument that's ever been built ligo. i just i wonder what like listening to. led zeppelin sounds on this thing. because it's so isolated i mean this is. like uh. i don't know no background noise nope no.

back it's wow. wow. wow that so when you were first. conceiving this um. i would probably uh if i was. knowledgeable enough kind of uh laugh. off the possibility this is even. possible i'm sure. like how many people. believe that this is possible did you. believe oh oh uh i did. i didn't know that we needed for sure. that we needed active when we started we.

did just passive but we were doing the. tests to develop the active. to add as a second stage which we ended. up needing. um but there was a lot of. you know now now there was a lot of. skepticism a lot of us especially. astronomers. felt that money was being wasted because. we were all so expensive. doing what i told you is not cheap so it. was. kind of controversial i was funded by. the national science foundation.

can you just linger on this just for a. little longer with the actuator thing. the act of canceling it um. do you remember. like little experiments that were done. along the way to prove to the team to. themselves that this is even possible. so from our. because i work with quite a bit of. robots. and to me the idea that you could do it. this precisely. is uh humbling and embarrassing frankly. because like this is another level of.

precision that i can't even. um because robots are a mess. and this is basically. one of the most. precise robots ever. right so like uh can you is there uh. yeah do you have any like small scale. experiments that were done that's just. believe this is possible yeah and larger. scale we made we made uh test uh. chan that also has to be in vacuum too. but we made test chambers that had this.

system. in it our first mock of the system so we. could test it. and. optimize it and make it work but it's. just a mechanical engineering problem. okay. [Laughter]. humans are just ape descendants i gotcha. i gotcha uh is there any video of this. like um. some kind of educational purpose. visualizations of this act of canceling. uh i don't think so.

i mean is this does this live on. well we work for parts of it for the. active canceling we worked with for the. instruments for the sensor and. instruments we worked with uh. a small company and met near where you. are because it was our mit people that. got them that were you know interested. in the problem because they thought they. might be able to commercialize it for. making stable tables to make. microelectronics for example which are.

limited by the how stable the table is. i mean at this point it's a little. expensive. so you never know you never know where. this leads. okay so. maybe on the. let me ask you just. sticking it a little longer this silly. old mechanical engineering problem uh. what was uh. to you kind of the darkest moment. of what was the hardest. stumbling block to get over on the.

engineer side like was there any time. where there's a doubt where it's like. i'm not sure we'll be able to do this. a kind of uh engineering challenge that. was hit do you remember anything like. that i think the one that that. my colleague at mit ray weiss worked on. so hard and uh. was. much more of a worry than this this is. only a question if you're not do it well. enough you have to keep making it better. somehow. but. this whole. huge instrument has to be in vacuum.

and. the vacuum tanks are you know this big. around and uh so it's the world's. biggest high vacuum system and the cons. so how do you make it first of all. uh how do you make this four meter long. sealed vacuum system it has to be made. out of four kilometers four kilometers. long would i say something else meters. four or four kilometers long big. difference yeah and uh so but to make it. yeah we started with uh.

uh a roll of stainless steel and then we. spi roll it out like a spiral so there's. a spiral weld on it. okay so. the engineering was fine we did that we. worked through. very good companies and so forth to. build it. uh the big worry. it was. what if you develop a leak. this is a high vacuum not just vacuum. system. typically in your in a laboratory if.

there's a leak you put. helium around. the. the thing you have and then you detect. where the helium is coming in but if you. have something as big as this you can't. surround it with helium so you might not. actually even know that there's a leak. and it will be affecting well we we have. we can measure. the. how good the vacuum is so we can know. that but there a leak can develop and. and then we don't how do we fix it or. how do we find it.

and uh so that was you asked about a. worry that was always a really big worry. uh what's the difference between a high. vacuum and uh and a vacuum what what is. high vacuum that's like some. a delta close to vacuum is there some. threshold well there's a unit. high vacuum is uh. when the vacuum and the units that are. used which are tors there's 10 to the. minus 9. there's high vacuum is usually used in.

small places the biggest vacuum system. period is that cern in this big particle. accelerator but the high vacuum where. they need really good vacuum so. particles don't scatter and it is. smaller than r so ours is a really large. uh. uh high vacuum system i don't know this. is so cool i mean this is basically. by far. the greatest listening device. ever built by human the fact that like. descendants of apes could do this.

that evolution started with single cell. organisms. i mean is there any more i'm a huge uh. theory it's like yeah yeah but like. bridges when i look at bridges. from a civil engineering perspective. it's one of the most beautiful creations. by human beings it's physics. you're using physics to construct. objects that can support huge amount of. mass. and it's like structural but it's also. beautiful and that humans can. collaborate to create that throughout. history and then you take this on. another level.

this is this is like. this is like. exciting to me beyond measure that. humans can create something so precise. but but another concept lost in this you. just said you started talking about. single cell yeah okay. you have to realize this discovery that. we made that everybody spot off on. happened. 1.3 billion years ago. somewhere and then the signal came to us. 1.3 billion years ago we were just. converting on the earth from single cell.

to multi-cell life. so when this actually happened this. collision of two black holes yeah we. weren't here we weren't even close to. we're both developing a single. yeah we were at we're going from single. cell to multi-cell life at that point. all to meet up with this at this point. yeah. wow that's like uh that's almost. romantic how though. it is. uh okay so. on the human side of things it's kind of.

fascinating because you're talking about. over a thousand people team for ligo. yeah uh that started out with uh you. know around a hundred. and you've uh. for parts of the time at least led this. team. what does it take to lead a team like. this of incredibly brilliant. theoreticians and engineers. and just a lot of different parties. involved a lot of egos.

a lot of ideas you you had this fun. funny example i forget where. where in publishing a paper you have to. all agree on like uh. you know the phrasing of a certain. sentence or the title of the paper and. so on that's a very interesting simple. example i'd love you to speak to that. but just in general how. what does it take to lead this kind of. team. okay uh i think the the general. idea. is one we all know you wanna you wanna.

you wanna to get. where the. the. sum of something is more than the. individual parts is what we say right. yeah. so that's what you're trying to achieve. yes okay how do you do that actually. mostly if we take. multiple. objects or people and when you put them. together the sum is less. yes. why because they overlap. so you don't have individual things that. you know this. person does that this person does that.

then you get exactly the sum but what. you want is to develop where you get. more than what the individual. contributions are we know that's very. common people use that. expression everywhere and it's the. expression that has to be. kind of built into how people feel it's. working because if you're. part of a team. and you realize that somehow the team is. able to do more than the individuals. could do themselves then they buy on. kind of in terms of the.

process so that's the. that's the goal that you have to. have is to to achieve that and that. means. that you. have to. realize. parts of what you're trying to do. that require. not that one person couldn't do it it. requires the combined talents to be able. to do something that neither of them. could do themselves and we have a lot of. that kind of thing and i think.

um i mean. build into the some of the examples that. i gave you. and so. uh how do you then so so the key almost. in anything you do is the people. themselves right so. in our case. the first and most important was to. attract. to spend years of their life on this and. the best possible people in the world to. do it so. the only way to convince them is that.

somehow it's. better and more interesting for them. than what they could do themselves. and so that's part of this. uh idea that's it yeah that's powerful. but nevertheless there's best people in. the world there's egos is there. something to be said about managing egos. the human problem is always the hardest. and so there's that's an art not. a science i think. i think the fact here that. combined.

there's a was a romantic goal. that we had to you know do something. that people hadn't done before which was. um. important scientifically and and a huge. challenge. uh enabled us to say take. and get uh i mean what we did just to. take an example we use the light to go. in this thing comes from lasers. we need a certain kind of laser so. uh the kind of laser that we use there.

were three. different institutions in the world that. had the experts that do this maybe in. competition with each other. so we got all three to join together and. work with us uh to work on this as an. example so that you had and they had the. thing that they were working together on. a kind of object that they wouldn't have. otherwise. and. were part of a bigger team where they. could discover something that. isn't even engineers these are engineers.

that do lasers so and they're part of. our laser physicists and. so could you describe. the. moment. or the period of time. when finally this incredible creation of. human beings. led to a detection of gravitational. waves. it's a long story unfortunately this is. a part that. uh we started failures along the way. kind of thing or all failures that's all. that's built into it.

okay if you're not a uh if you're not. mechanical engineering. you build on your failures that's. expected so we're trying things that no. one's done before so it's technically. not just gravitational waves and so it's. built on failures. but anyway we we did. before me even the the. people did. r d on the concepts. but starting in 1994 we got money from. the national science foundation to build.

this thing. it took about five years to build it so. by 1999 we had. built the basic. unit. it did not have. active seismic isolation at that stage. didn't have some other things that we. have now. what we did at that at at the beginning. was. uh. stick to. technologies that we had. at least enough knowledge that we could.

make work or had tested in our own. laboratories. and so then we put together the. instrument. we made it work. it didn't work very well but it worked. and. we didn't see any gravitational waves. then we figured out what limited us and. we went through this every year for. almost 10 years. never seen gravitational waves we would. run it. looking for gravitational waves for. months.

learn what limited us fix it for months. and then run it again. eventually we. knew we had to take another big step and. that's when we made several changes. including going adding these active. seismic isolation which turned out to be. a key. and we. fortunately got the national science. foundation to give us another. couple hundred. million dollars 100 million more and.

we rebuilt it our fixed. or improved it. and uh. then in ninth uh in. 2015 uh we turned it on. and uh. we um. almost instantly saw uh this first. collision of two black holes. um. and. then then we went through a process of. do we believe what we've seen yeah i.

think i think you're one of the people. that went through that process it sounds. like some people immediately believed it. yeah and and then you were like so as. human beings we all have different. reactions to almost anything and so. quite a few of my colleagues had a. eureka moment immediately i mean it's. that's amazing. the the the figure that we. that we put in our paper. first is just data we didn't have to go. through you know fancy computer programs. to do anything.

and. and we showed next to it uh the. calculations of einstein's equations it. looks just like the what we detected wow. and we did it in two different detectors. halfway across the us so it was pretty. convincing but. but you don't want to. you don't want to fool yourself so we. had a. being a scientist. we had a. for me we had to go through and try to. understand that the instrument itself. which was new i said we had rebuild it.

couldn't somehow generate. things that look like this. that took some tests and then. the second you'll appreciate more. we had to somehow convince ourselves we. weren't hacked in some clever way cyber. security question yeah even though we're. not on the internet the the but yeah. no it can be physical access too yeah. that's that's fascinating it's. fascinating you would think about that i. mean. not not enough.

i mean because it's it's uh it matches. prediction. so the chances of it actually being. manipulated is very very low. but nevertheless. we still could have disgruntled old. graduate students who had worked with us. earlier that who. want you to i don't know how that's. supposed to embarrass you i suppose yeah. i suppose i see but. but about what i think you said within a. month you kind of convinced yourself. something within a month we convinced. ourselves uh we kept a thousand.

collaborators quiet during that time. then we spent another that's funny month. or so uh. trying to understand what we'd seen. so that we could do the science with it. instead of just putting it out to the. world and let somebody else understand. that it was two black holes and what it. was the fact that a thousand. collaborators were quiet. is a really strong indication that this. is a really close-knit team yeah over. and they're around the world. or either strong.

uh either strong knit or tight-knit or. had a strong dictatorship or something. yeah either fear or love you can rule by. fear of love yeah you can go back to. mecca valley yeah. all right well this i mean. this is really exciting that that was. that that's a success story because it. didn't have to be a success story. right. i mean eventually perhaps you could say. it'd be an effect but it could have. taken it over a century to get oh yeah.

yeah it's uh and. and it's only downhill now kind of. [Laughter]. what do you mean it's only uh you mean. with gravitational waves well we're yeah. we've it's we've now we now. uh well now we're off because of the. pandemic but when we turned off we were. seeing. some sort of gravitational wave event. each week. and now we're fixing we're fixing we're. adding features where it'll probably be.

when we turn back on next year it'll. probably every one every couple days. and they're not all the same so it's. learning about what's out there in. gravity instead of just optics and. so it's all. uh great we're only limited by. the fantastic thing other than that this. is uh. a great field and you know it's all new. and so forth is that experimentally the. the great thing is that uh. we're limited by.

technology and technical limitations not. by science. so. the the the. uh. another. a really important discovery that was. made before ours. was what's called the higgs boson made. on the big accelerator at cern you know. this huge accelerator they discovered a. really important thing it's. you know we have einstein's equation e. equals m c squared so energy makes mass.

or mass can make energy and that's the. bomb. but the mechanism by which that happens. not fission but but how do you create. mass from energy. was never. understood. until there was a. a theory of it about. 70 years ago now. and. so they discovered it's named after a. man named higgs it's called the higgs. boson.

and so it was discovered. but since that time and i i worked on. those. experiments since that time they haven't. been able to progress very much further. a little bit but not a lot further and. the difference is that we're really. lucky we're in. in what we're doing in that. there. uh you're you see this higgs boson but. there's tremendous amount of other. physics that goes on and you have to. pick out the needle in the haystack kind. of of physics you can't make the physics. go away it's there.

in our case we have a very weak signal. but once we get good enough to see it. it's weak compared to where we've. reduced the background but the. background is not physics it's just. technology you know it's getting. ourselves better isolated from the earth. or getting a more powerful laser. and so each time each since 2015 when we. saw the first one we continually can. make improvements that are enabling us.

to turn this into a. a real science to do astronomy a new. kind of astronomy it's a little like. astronomy i mean. galileo. started the field i mean he basically. took lenses that were made for classes. and he didn't invent the first telescope. but made a. looked at. neptune. and saw that it had four moons. that was the birth of. not just using your eyes to understand.

what's out there. and since that time we've made better. and better telescopes obviously and. astronomy thrives. and in a similar way we're starting to. be able to. for you know crawl but we're starting to. be able to do that with gravitational. waves it's and it's going to be more and. more that we can. do is we can make better and better. instruments because as i say it's not. limited by. um. picking it out of other yeah it's not.

limited by the physics so you have an. optimism about engineering that event. you know as we. as human progress marches on. engineering will always uh find a way to. uh. to build a large enough device accurate. enough device to detect the size as long. as it's not limited by physics yeah. they'll do it. so. you. two other folks and the entire team.

won the nobel prize. for this yeah big effort. there's a million questions i can ask. for but. looking back. where does the nobel prize fit into all. of this. you know if you think hundreds years. from now. i venture to say that people will not. remember the winners of a prize.

but they'll remember creations like. these maybe i'm romanticizing. engineering. but i guess i want to ask how important. is the nobel prize in all this. well that's a it's a complicated. question it's uh. as a physicist it's something if you're. if you're trying to win a nobel prize. forget it because they give you know. one a year. so there's like there's been. 200 physicists who've won the nobel.

prize since 1900 and. and so that's. you know. and so things just have to fall right so. your goal cannot be to win a nobel prize. it wasn't my dream. uh. it's a. it's. uh tremendous for science i mean why the. nobel prize for a guy that made dynamite. and stuff is you know what it is it's a. long story but. it's the one day a year where actually. the science that people have done is all.

over the world and so forth. forget about the people again you know. it is really good for for science. celebrating science it celebrates. science. for. you know several days different fields. uh you know chemistry. medicine and so forth. and uh. everybody doesn't understand everything. about these they're. generally a fairly abstract but then. it's you know it's. on the front page of newspapers around. the world so it's really good for. science it's not easy to get science on.

the front page of the new york times. it's not there. uh should be but it's not. and uh. so the nobel prize is important in that. way uh. it's otherwise you know. i have a certain celebrity that i didn't. have before and. um and now you get to be a celebrity. that advertises science it's a mechanism. to. uh to remind us how incredible well.

how much credit science deserves and. everything well it has a little bit more. one thing i didn't expect which is good. is that you know. we have a a government. i'm not picking on ours necessarily but. it's true of all governments are not run. by scientists in our case it's run by uh. lawyers and businessmen yep okay. uh and at best they may have an aide or. something that knows a little science so.

so our country is. and all countries are hardly. hardly take into account. science. in. making decisions yes okay. and. having a nobel prize the uh. people in those positions actually. listen. so. you have more influence i don't care. whether it's about global warming or. what the issue is there's some.

influence which is lacking otherwise. and uh i. people pay attention to what i say if i. talk about global warming they wouldn't. have. uh before i had the nobel prize. uh yeah this is very true you're like. the celebrities who talk uh. celebrity has power uh celebrity has. power and that's that's and that's a. good thing that's a good thing yeah uh. singling out people i mean on the other. side of it singling out people. has all kinds of you know whether it's.

for academy awards or for this. have unfairness and arbitrariness and so. forth and so on so. uh. you know that's the other side of the. coin jessica said especially with the. huge experimental projects like this. you know it's a large team. and it does the nature of the nobel. prizes singles out a few individuals to. represent the team yeah. nevertheless is a beautiful thing uh. what are ways to improve ligo in the. future increase the sensitivity.

i've seen a few ideas that are kind of. fascinating. is are you interested in them. sort of looking i'm not speaking about. five years perhaps you could speak to. the next five years but also the next. hundred years. yeah so let me let me talk to both the. instrument and the science okay. so that's they go hand in hand i mean. the thing that i said is if we make it. better. we see more kinds of weaker objects and. we do astronomy okay. we're very motivated to make a new.

instrument. which will be a big step the next step. like making a new kind of telescope or. something. and. the ideas of what that instrument should. be uh. haven't converged yet there's different. ideas in europe they've done more work. to kind of. develop the ideas. but they're different from ours and we. have ideas. so. but i think over the next few years. we'll develop those.

the idea is to make an instrument that's. at least 10 times better than what we. have. what we can do with this instrument 10. times better than that. 10 times better means you can look 10. times further out. 10 times further out is a thousand times. more volume. so you're seeing much much more of the. universe the big change. is. that if you can see far out you far you. see further back in history yeah you're. traveling back in time.

yeah and so. we can start to do what we call. cosmology instead of a astronomy or. astrophysics. cosmology is really the study of the. evolution of the. oh interesting yeah yeah and uh so then. you can start to hope to get to the. important problems having to do with uh. how. the universe began how it evolved and so. forth which we really.

only study now with. optical. instruments or. electromagnetic waves. and early in the universe those were. blocked because. basically it wasn't transparent so the. photons couldn't get out. when everything was too dense what do. you think sorry on this tangent what do. you think an understanding of. gravitational waves from earlier in the. universe can help us understand about. the big bang and all that stuff yeah. that's that's so but it's a non.

it's a it's a. it's another perspective on the thing is. is there some insights you think could. be revealed just to. help a layman understand sure first we. don't understand we use the word big. bang we don't understand the physics of. what the big bang itself was. uh. so i think. my my. and in the early stage there were. particles and there was a huge amount of. gravity and mass being made and so.

uh. the big. the so i'll say two things one is. how did it all start how did it happen. and i'll give you at least one example. that we don't understand what we should. understand. we don't know why we're here. yes. no we do not. i don't mean it philosophically. i mean in terms of physics okay. now what do i mean by that if i go into. my laboratory at cern or somewhere and i.

collide particles together put energy. together i make as much antimatter as. matter right. antimatter then annihilates matter and. makes energy so. in the early universe there. you made somehow. somehow. a lot of matter and anti-matter but. there was an asymmetry somehow there was. more matter and anti-matter. that matter and anti-minor annihilated. each other at least that's what we think. and there was matt only matter left over.

and we live in a universe that we see. that's all matter. we don't have any idea we have an ideas. but we don't have any. we don't have any way to understand that. at the present time with the physics. that we know. can ask a dumb question does. anti-matter. have anything like a gravitational field. to uh send signals. so. how how does this asymmetry of matter. anti-matter.

could be investigated or further. understood by observing gravitational. fields or weirdnesses in gravitational. fields i i think that. in principle if there were you know. anti-neutron stars instead of just. neutron stars we would see. different kinds of signals but. it didn't get to that it's we live in a. universe that we've done enough looking. because we don't see anti-pro matter. anti-protons anywhere no matter what we. look at that it's all made out of matter.

there is no antimatter except we go in. our laboratories. so. but when we go in our laboratories we. make as much antimatter as matter so. there's something about the early. universe that made this. asymmetry so we can't even explain why. we're here that's what i meant yeah. physic physics-wise not you know. uh not in terms of. how we evolved and all that kind of. stuff so uh so there might be. inklings of uh.

of some of the physics. that uh gravitational so so. gravitational waves don't get obstructed. like light so i said light only goes to. 300 000 years so it goes back to the. beginning so if you could study the. early universe with gravitational waves. we can't do that yet. then. it took 400 years to be able to do that. with. optical but. then you can really understand the very. maybe understand the very early universe.

so in terms of uh. questions like. why we're here or what the big bang was. um we should be we can in principle. study that with gravitational waves so. to keep. moving in this direction it's a unique. kind of uh way. to understand our universe do you think. there's more nobel prize level ideas to. be discovered in relation to. i'd be shocked if their gravitational. waves if there isn't uh not even going. to that which is a very long range.

problem but. i think that. we only. see. with electromagnetic waves four percent. of what's out there. there must be we looked for things that. we knew should be there. there should be. i would be shocked if there wasn't. physics objects science. and with gravity that doesn't show up in.

everything we do with telescopes so. i think we're just. limited by not having powerful enough. instruments yet to do this. do you have a preference i keep seeing. this uh. e-lisa idea. yeah. is it. do you have a preference for. earthbound or space-faring. mechanisms for they're complementary. it's a little bit more signal it's a.

it's completely analogous to what's been. done in astronomy right so astronomy. from the time of galileo. was done with uh visible light yeah. a strong the big advances in astronomy. in the last 50 years are because we have. instruments that look at the infrared. microwave. ultraviolet and so forth so. looking at different wavelengths has. been important basically going into. space. means that we'll look at instead of the. audio band which we look at as we said.

on the ear surface we'll look at lower. frequencies it's so it's completely. complementary and it starts to be. looking at different frequencies just. like we do with astronomy isn't it. it seems almost incredible to me. engineering-wise just like on earth to. send something that's kilometers across. into uh into space is that is it harder. to engineer. then it actually is a little different. it's three satellites.

separated by hundreds of thousands of. kilometers. and they send a laser beam from one to. the other. and uh. if they. the distance if the triangle changes. shape a little bit they detect that from. the gravity the passage did you say. hundreds of thousands of kilometers yeah. sending lasers to each other. [Laughter]. okay it's just engineering. [Laughter]. uh is is possible though.

yes. okay. uh that's that's just incredible because. they have to maintain i mean the. precision here is probably there there. might be some more what is it maybe. noise is a smaller problem. i guess there's no vibration to do. to worry about like seismic stuff. so getting away from earth maybe you get. away from yeah those parts are easier. they don't have to measure it as. accurately at low frequencies. uh but they have um a lot of tough.

engineering problems the. the. in order to detect that the. the uh gravitational waves affect things. the. sensors have to be what we call free. masses just like ours are isolated from. the earth they have to isolate it from. the satellite. and that's a hard problem they have to. do that pretty not as well as we have to. do it but. very well and. they've done a test mission and the.

engineering seems to be. at least in principle in hand. this will be in the twenty thirties. twenty thirties yeah. this is incredible this is uh. this is this is incredible uh. let me ask about black holes um yeah so. what we're talking about is observing. uh. orbiting black holes. uh that i get i saw the terminology of. like binary black hole systems. is that's that's when the the one that's.

when they're dancing. okay going around each other just like. the earth around the sun okay is that. weird that there's black holes going. around each other. so the finding binary systems of stars. is similar to finding binary systems of. uh black holes well they were once stars. so. um. so. we haven't. said what what a black hole is. physically yet yeah so what's a black. hole so. black hole is a is first it's a. mathematical concept or a physical.

concept and that is. a region of space. so it's simply a region of space where. the curvature of space-time meaning the. gravitational field is so strong. that nothing can get out yeah. including light. and there's light gets bent. in gravitational if the gravitations if. the space time is warped enough and so. even light gets bent around and stays in. it so that's concept of a black hole so.

it's not a f. and maybe you can make maybe it's a. that's a concept. that didn't say how they come about. and there could be different ways they. come about the ones that we are seeing. there's a we're not sure. it's what we're trying to learn now is. what they but the general. expectation. is that they come. at the bl these black holes happen when.

a star dies. so what does that mean that a star dies. what happens. a star like our sun. basically makes heat and light by fusion. it's made of. and as it burns it burns up the hydrogen. and then the helium and then. and slowly works its way up to the. heavier and heavier elements that are in. the star. and when it gets up to iron the fusion. process doesn't work anymore.

and so the stars die. and that happens to stars and then they. do. what's called a supernova what happens. then. is that a star is a delicate balance. between an outward pressure from fusion. and. light and burning. and an inward pressure of gravity trying. to pull the. masses together once it burns itself out. it goes. and it collapses and that's a supernova. when it collapses all the mass that was.

there is in a very much smaller. space. and if a star if you do the calculations. if a star is big enough. that can create a strong enough. gravitational field to make a black hole. our sun won't. it's too small too small. and we don't know exactly. what it but it's usually thought that a. star has to be at least three times. as big as our sun. to make a black hole but that's the.

physical way there you can make black. holes. that's the first um. explanation that one would give for the. for what we see. but it's not necessarily true we're not. sure yet what we see in terms of for the. origins of black holes no the black. holes that we see. in gravitational waves so the but you're. also looking for the ones who are binary. solar systems like so they're binary. systems but they could have been made. from binary stars so there's binary.

stars around so that's. that's so so that's so this first. explanation is that that's what they are. gotcha um. other. explanati but but what we see. has some puzzles this is kind of the way. science works i guess yeah um. we see. heavier ones. than. up to. we've seen one system that was 140 times. the mass of our own sun.

that's not believed to be possible. with the. parent being a big star because big. stars can only be so big. uh or they uh are unstable it's just the. the fact that they live in an. environment that makes them unstable. so. uh the fact that we see bigger ones they. maybe. come from something else it's possible. that they were. uh made in a different way by.

little ones eating each other up or. maybe they were made. or maybe they came with the big bang the. prime what we call primordial which. means they're really different they came. from that we don't know at this point if. they came with a big bang then maybe. they account for. what we call dark matter or some of it. like there was a lot of them if they. came with them and yeah because there's. a lot of dark matter yeah. but uh will gravitational waves give you. any kind of an um intuition about the.

origin of these oscillators we think. that if we see um the distributions. enough of them the distributions of. their. masses the distributions of their how. they're spinning so we can actually. measure when they're going around each. other. whether they're spinning. you know like this direction of the spin. or no the orientation whether the whole. system has any. wobbles. what. so this is this is now okay.

we're doing that and then you're. constantly kind of crawling back and. back into and we're crawling back in. time and seeing how many there are as we. go back and so do they point back so. you're like uh what is that discipline. called cartography or something you're. like mapping. this the early universe. via the lens of gravitational. waves not yet the early universe but at. least back and forth earlier yeah right. so. um. so black holes are this.

mathematical phenomenon but they come. about in different ways we have a huge. black hole. at the center of our galaxy and other. galaxies. those probably were made some other way. we don't know when the galaxies. themselves. had to do with the formation of galaxies. we we don't really know so the fact that. we use the word black hole. the origin of black holes might be quite. different depending on. how they happen. they just have to in the end have a. gravitational field that will bend. everything in.

how do you feel about black holes as a. human being there's a there's this thing. that's. nearly infinitely dense can. doesn't let like light escape. isn't that kind of terrifying feels like. the stuff in nightmares i think i think. it's it's an opportunity. to to do what exactly. so uh. like the early universe is an. opportunity if i we can study the early. universe we can learn things like i told. you and here again.

we have an embarrassing situation in. physics yes. we have two wonderful theories of. physics. one based on quantum mechanics. quantum field theory and. we can go to a big accelerator like at. cern and smash particles together and. almost explain anything that happens. beautifully using quantum field theory. and quantum mechanics. then we have another theory of physics. called general relativity which is what. we've been talking about most of the. time which is fantastic at describing.

uh things at high velocities long. distances. you know uh and so forth so. that's not the way it's supposed to be. uh we're trying to create a theory of. physics not two theories of physics. so we have an embarrassment that we have. two different theories of physics. people have tried to. make a unified theory what they call a. unified there you've heard those words.

for decades. they still haven't that's been primarily. done theoretically or try they people. actively do that. my personal belief is that the. like. much of physics we need some clues. so we need some experimental evidence so. where is there a place if we go to cern. and do those experiments gravitational. waves or general relativity don't matter. yes if we go to study you know our black.

holes. elementary particle physics doesn't. matter we're studying these huge objects. so where might we have a place where. both phenomena have to be satisfied an. example is black holes inside black. holes yeah. so we can't do that today. but when i think of black hole it's a. potential. treasure chest. of. understanding the fundamental problems. of. physics. and maybe. can give us clues.

to how we bring to the embarrassment of. having two theories of physics together. that's my own. romantic what's the worst that could. happen it's so enticing just go in and. look. do you think um. how far are we away from figuring out. the unified uh. theory of physics the theory of. everything i think what's your sense who. will. solve it like what discipline will solve. it yeah uh. i i think.

uh so little. progress has been made uh. without. more experimental clues as i said that. we're not uh. we're just not able to. say that we're close without some clues. the best the closest. the most. popular theory these days that might. lead to that is called string theory. yeah. the problem with string theory is it.

works. uh it solves a lot of beautiful. mathematical problems we have in physics. and uh. and uh. it's. it's uh. very satisfying theoretically. but it has almost no predictive. maybe no predictive ability because. it is a theory that works in 11. dimensions. we live in a physical world of. three space and one time dimension.

in order to make predictions. in our world with string theory you have. to somehow get rid of these other. seven. dimensions that's done mathematically by. saying they curl up on each other on. scales that are too small to affect. anything here. but how you do that and that's okay. that's an okay argument but how you do. that. is not unique. so that means if i start with that. theory and i go to our world here i.

can't uniquely go to it. and if i can't. it's not predictive and that's that's. actually and that's a killer that's a. killer and string theory is it seems. like from my outsider's perspective has. lost favor over the years perhaps. because of this very it's a lack of. predictive power i mean that science. has to connect to something where you. make predictions as beautiful. as it as it might be so i don't think. we're close i think we need. some.

experimental clues it may be. that information on. something we don't understand presently. at all like dark energy or. probably not dark matter but dark energy. or something might give us some ideas. but. i i don't think we're. i can't envision right now. um in the short term meaning you know. the horizon that we can see. how we're gonna uh bring these two. theories together.

a kind of um. two-part question maybe just asking the. same thing in two different ways. one one question is. do you have hope that humans. will colonize. the uh the galaxy so expand out become a. multi-planetary species another way of. asking that from a gravitational and a. propulsion perspective do you think. we'll come up with ways to travel close. to the speed of light or maybe faster. than the speed of light. which would make it a whole heck of a.

lot easier to to expand out into the. into the universe. yeah. uh. well i think. you know we're not. that's a very futuristic i think we're. not that far from being able to. make a one-way trip to mars. that's a that's then a. question of uh. whether people are willing to send.

somebody on a one-way trip but oh i. think they are i think there's a lot of. exp the explorers burn bright and with. their hearts yeah exactly people wanting. to die so. the opportunity to to explore new. territory yeah so uh. you know with this this recent. landing on mars is pretty impressive. they have a little helicopter that can. fly around you can imagine. you can imagine in the not too distant. future that you could have i don't think. civilizations colonizing i can envision.

but i i can envision something more like. the south pole. we haven't colonized. antarctica because it's. all ice and cold and so forth but we. have. uh stations so we have a station that's. self-sustaining at the south pole that. i've been there. it has oh really yeah. what's that like. uh and. because that there's parallels there. to go to mars it's fantastic it is.

what's the journey like. the journey involves going uh the south. pole station is uh run. in the u.s by. by the national science foundation. i went because i was on the national. science board that runs the national. science foundation. and so you get a vip trip if you're. healthy enough to the south pole to. see it. uh which i took uh. you fly from the u.s to australia to to.

christchurch in australia southern. australia. and. from there you fly to mcmurdo station. which is on the coast and it's the. station with about a thousand people. right on the coast of antarctica. uh it's about a. seven or eight hour flight and they. can't predict the weather so when when i. flew from. christchurch to mcmurdo station they. tell you in advance you do it in a.

military. aircraft they tell you in advance that. they can't predict whether they can land. because they have to land on uh. reassuring. yeah and so about. halfway the pilot got on and said uh. sorry this is uh they call it a. boomerang flight you know boomerang goes. out and goes back. so we had to stay a little while in. christchurch but then we eventually went. to. mcmurdo station and then. flew to the south pole the south pole.

itself. is. when i was there was minus 51 degrees. that was summer. uh. it uh. zero humidity. and uh. and it's about. 11 000 feet altitude. because it's. never warm enough for anything to melt. so it doesn't snow very much but it's. about 11 000 feet.

of snowpack so you land in a place. that's high altitude. um. cold as could be. and dry and incredibly dry. which means you have a physical. adjustment. the. place itself is uh. it's fantastic they have this great. station there they they do astronomy at. the south pole nature wise is it. beautiful. what's the is what's the experience like.

or is it like visiting any town. no it's very small there's only um. less than 100 people there even when i. was there. you know. there were about. 50 or 60 there and in the winter there's. less half of that their winter when yeah. it's real cold it gets really cold yeah. and but it's but it's. it's a station i i think. and that's. i mean we haven't gone beyond that uh.

on the coast of antarctica they have. greenhouses and they're self-sustaining. in mcmurdo station but we haven't really. settled more than. that kind of thing in antarctica which. is a big. uh. a country or you know. a. big plot a big. piece of land so. i don't. i can't envision kind of. colonizing at people living so much as.

much as i can see. the equivalent of the south pole station. well in the computing world there's a. idea of. you know backing up your data and then. you want to do off-site backup. uh you know to make sure that if the. whole thing burn if your whole house. burns down then you can have a backup. offsite of the data i think the. difference between antarctica and. and mars is mars is a off-site backup. that if we have nuclear war whatever the. heck might happen here on earth it'd be.

nice to have a backup elsewhere and uh. be nice to have a large enough colony. where we sent a variety of people except. like. uh a few silly astronauts and suits you. know have an actual vibrant. um get a few get a few musicians and. artists up there get a few uh. maybe like one or two computer. scientists those are essential maybe. even a physicist so. i'm not sure yeah maybe not. so that comes back to something you. talked about earlier which is fermi the.

paradox family's paradox because you. talked about having to escape yeah. but. and so the missing one one number you. don't know how to use in fermi's. calculation or drake who's done it. better is how long do civilizations last. yeah. before they. are we you know we've barely gotten to. where we can communicate with. electricity and magnetism and maybe. we'll wipe ourselves out pretty soon so. are you hopeful in general like you. think we've got another couple hundred.

years at least. or are you worried. well i and no i'm i'm i'm hopeful but i. don't know if i'm hopeful in the long. term. you know if you say. you know. uh. are we able to. to go for another couple thousand years. i'm not sure i you know i think. we have where we where we started the. fact that we can do things that don't. allow us to. kind of keep going or there can be.

whether it you know ends up being a. virus that we create or. ends up being the equivalent of nuclear. war or something else. it's not clear that we can control. things well enough. so speaking of really cold conditions. and uh not being hopeful and eventual. suffering and destruction of the human. species let's let me ask you about. russian literature. you mentioned uh how's that for. transition i'm doing my best here you uh. you mentioned that you used to love.

literature when you were younger and you. were even. or hoping to be. a writer yourself that was the. motivation. and some of the books i've seen that you. listed. that were. inspiring to you was was from russian. literature like uh i think tolstoy. dostoyevsky solzhenitsyn. yeah right um maybe in general you can. speak to your fascination with russian. literature or yeah in general will you. pick up from those all. not surprised you picked up on the.

russian literature i'm sorry your. background but. uh. when i when when i you should be. surprised i didn't make the entire. conversation about this that's that's. the real surprise when when. i didn't really. become a. physicist or. want to go in science until i started. college so when i was younger i. i was good at math and that kind of. stuff but i didn't really i came from a.

family nobody went to college and i. didn't have any mentors. so but i'd like to read when i was. really young and so when i was very. young i i read i always carried around a. pocketbook and read it. and uh. my mother read these mystery stories and. i got bored by those eventually and then. i discovered real literature i don't. know what age but about 12 or 13. and so then i started reading. uh good literature and there's nothing. better than russian literature of course.

and like reading. reading. good literature so i. i. read. quite a bit of russian literature. at that time. and so you asked me about the well. i don't know i say a few words said. dostoevsky so what what about dostoevsky. for me. um. dostoevsky was important.

into i mean i've read a lot of. literature because it's kind of the. other thing i do with my life and. he made two incredible in addition to. his own literature. he influenced literature tremendously by. having. uh. i don't know how to pronounce polyphony. so he's the first real serious author. that had. multiple narrators. and that's a that he absolutely is the. first.

and he also was the first. he began existential literature. so. the most important book that i've read. in the last year when i've been forced. to be isolated. was existential literature it was i. decided to reread. camous the plague. oh yeah that's a great book it's a great. book and it's right now to read it it's. fine i think that book is about love. actually. a love for his humanity it is but it has.

all the men it has all the. you should if you haven't read it in. recent years i had read it before of. course but. to read it during this because it's. about a plague so it's really fantastic. to be done but that reminds me of. you know he was a great existentialist. but the beginning of existential. literature was dostoevsky. yeah so in addition to his own you know. great novels he had a tremendous impact. on on uh. on literature and there's also for.

dostoevsky unlike most of their. existentialists. he was. at least in part religious i mean their. uh religiousity would permeated his. idea i mean one of my favorite books of. his is the idiot and. his which is a christ-like figure in. there well there's prince miskin is that. michigan yeah yeah michigan yeah in. michigan yeah that's that's one uh thing. about there you write it in english i. presume yeah yeah yeah so that's the. names that's what gets a lot of people. is there's so many names so hard to.

pronounce they have to remember all of. them. it's like uh you have the same problem. but he was a great character so that. yeah i kind of uh. i have a. connection with him because i often. then the title of the book. the idiot is. i kind of i often call myself an idiot. because that's how i feel i feel so. naive about this world and i. i'm not sure. i'm not sure why that is maybe it's. genetic or so on but i.

um. i have a of a connection the spiritual. connection to that character to michigan. to michigan yeah that you're just in but. he was far from energy yet. no in some sense in some sense. but in another sense. maybe not of this in another sense he. was yeah i mean he was a bumbler bunker. yeah. but uh you also mentioned soulja nitsan. yeah very interesting yes he did uh and. and he always confused me of course he. was really uh.

really important in uh. writing about the. stalin and. first getting in trouble and then he. later he is. he he wrote about stalin in a way i. forget what it was what the book was in. a way that was very. critical of london. yeah he uh he's evolved through the. years he actually showed support for. putin eventually it was a very.

interesting. uh transition he took no. journey he took through thinking about. russia and the soviet union. but. i think what i get from him is basic um. it's like uh victor franco has a man. search for meaning i have a similar kind. of. sense of um. of the cruelty of human nature yeah. cruelty of indifference. but also the ability to find happiness.

in the small joys of life. that that's something there's nothing. like a prison camp that makes you. realize. you could still be happy with a very. very little well yeah he was he his. description of kind of how to make uh. how to go through a day and actually. enjoy it in a prison camp it's pretty. amazing. yeah oh and some prison camp i mean it's. the worst of the worst of the worst and. also just uh i i you know you do think. about.

the role of authoritarian states and um. in you know like hopeful idealistic. systems somehow leading to the suffering. of millions and i you know. it might be arguable but i think a lot. of people. believe that stalin. i think genuinely believed that he's. doing good for the world. and uh he wasn't. it's a very valuable lesson that. even evil people.

think they're doing good. otherwise it's too difficult to do the. evil. the best way to do evil is to believe. framing in a way like you're doing good. and then this is this is a very clear. picture of that which is the the gulags. and soulja is one of the best people to. reveal that yeah. the most recent thing i read it isn't. actually fiction uh was the. the woman i can't remember her name who. got the nobel prize about.

within the last five years. i don't know whether she's ukrainian or. russian but there are. interviews have you read that interview. of ukrainian survivors of. well i think she may be originally. ukrainian so i'm the book's written in. russian then translated into english and. many of the interviews are in moscow and. places. but she won the nobel prize within the. last five years or so. but what's interesting is that uh. these are people of all different ages.

all different uh uh. occupations and so forth and they're. reflecting on the. their reaction to. basically the present soviet system the. system they lived with before there's a. lot of. uh. looking back by a lot of them with uh. uh. well uh. it being much better before. yeah.

i don't know what i. in america we think we know the right. answer what it means to be um to build a. better world i'm not so sure i think. we're all just trying to figure it out. yeah they're just doing our best i i. think you're right. is there advice you can give to young. people today. besides reading russian literature at a. young age. um about how to find their way in life. how to find success in career or just. life in general.

uh. i i just. my own. belief it may not be very. deep but i believe it i think you should. follow your dreams. and you should have dreams and follow. your dreams if you can to the extent. that you can. and. we spend a lot of our time doing. something with ourselves in my case. physics in your case i don't know. whatever it is. machine learning and this.

uh. we should yeah i should have fun. what was wait wait wait drink follow. your dreams what uh what dream did you. have because. well well originally i was. because you didn't follow your dream. well that's the change along the way i. was gonna be okay but i changed what. happened that was what happened. oh i read i decided to take the most. serious literature course in my high. school which was a mistake i'd probably.

be a second-rate writer now and uh could. be a nobel prize winning writer and uh. uh. the. the book that we read. even though i had read russian novels. i was 15 i think uh cured me. from being a novelist destroyed your. dream yes cured you okay what was the. book moby dick okay. so why moby dick yeah why so i i've read.

it since. and it's a it's a great novel maybe it's. as good as the russian novel i've never. made it through i i thought it was too. boring it's too long okay your words are. gonna. mesh with what i say excellent and you. may have the same problem at uh older. that's why i'm not a writer. it may be. so the problem is. moby dick is. what i remember was there was a chapter. that was maybe 100 pages long. all describing this why there was ahab.

and the white whale and it was the. battle between ahab with his wooden peg. leg and the white whale. and there was a chapter that was 100. pages long in my memory i don't know how. long it really was. that described in detail the great white. whale and what he was doing and what his. fins were like and this and that and it. was so incredibly boring the word you. used. that i thought if this is great. literature. screw it.

okay. now why did i have a problem i know now. in reflection because i i still read a. lot and i i read that uh. novel. um you know after. i was. 30 or 40 years old. and the problem was simple i i diagnosed. what the problem was i that. novel in contrast to. the russian novels which are very. realistic and. you know point of view. is one huge metaphor.

oh yeah. at 15 years old i probably didn't know. the word and i certainly didn't know the. meaning of a metaphor yeah like why do i. care about a fish why are you telling me. all about this exactly is one big. metaphor so reading it later as a. metaphor i could really enjoy it. but the teacher gave me the wrong book. or maybe it was the right book because i. went into physics and so. uh. but it was it was truly i think i may. oversimplify but it was really that i. was too young to read that book because.

not too young to read the russian novels. interestingly but too young to read that. because i i probably didn't even know. the word and i certainly didn't. understand it as a metaphor. well in terms of fish i recommend people. read old man in the sea much shorter. much better it's still a metaphor though. so but you can read it just as a story. about a guy catching a fish and it's. still fun to read. i had the same experience. as you not with moby dick but later in.

college i took a course on james joyce i. don't understand why. i was majoring in computer science i. took a course on james joyce. and i was kept being told that he is. widely considered by many considered to. be the greatest. literary. writer of the 20th century. and i kept reading like i think so his. short stories the dead i think it's. called was very good. well not very good but pretty good. and then you listen he's very good it is. very good only the dead the final story.

is still rings with me today but then. ulysses was i i i got through ulysses. with the help of some cliff notes and so. on but. uh and so i did ulysses and then. finnegan's wake the moment i started. finning his wake. i said this this is stupid. this is that's when i went full into. like. um i don't know that's why i went full. kafka. bukowski like people who just talk about. the darkness of the human condition in. the fewest wars possible.

and without any of the. music of language. um so it was a turning point. uh as well i i wonder i wonder when is. the right time to do the. to appreciate the beauty of language. like even shakespeare i was very much. off put by shakespeare in high school. and only later i started to appreciate. it's its value in the same way. let me ask you a ridiculous question. okay um.

i mean because you've read russian. literature let me ask this one last. question. uh. i might be lying there might be a couple. more but what do you think is the. meaning of this whole thing. you're uh you got a nobel prize for uh. looking out into the trying to reach. back into the beginning of the universe. listening to the gravitational waves. uh. but that still doesn't answer the why. why are we here. beyond just the yeah the matter and.

antimatter. the philosophical question i felt a. philosophical question about the meaning. of life i'm probably not really good at. i think. that. the individual meaning. uh. i i would say rather simplistically is. whether you've made. a difference a positive difference i'd.

say for anything besides yourself. meaning you could. have been important to other people. or you could have discovered. gravitational waves that matters to. other people or something but something. beyond just existing on the earth. as an individual so. your life has meaning if you have. affected. um. either. knowledge or people or something beyond. yourself.

do you it's a simplistic. statement but it's about as good as i. and i have that's that may in all of its. simplicity it may be very true. do you think about uh. does it make you sad that this ride ends. do you think about your mortality. yeah uh. are you afraid of it. i'm not exactly afraid of it but. saddened by it and uh.

uh. you know i'm old enough to know that. i've. lived most of my life. and. i enjoy being alive. i can imagine being sick and not wanting. to be alive but i'm not and. so. um i'm. not getting a good ride. yeah i'm not and i'm not happy to see it. come to an end i'd like to see it. prolonged. but uh. i i don't uh.

i i i don't. fear the dying itself or that kind of. thing it's more i'd like to prolong. uh what. is i think. a good life that i'm. living and still living it's kind of. it's sad to think that the finiteness of. it. is the thing that makes it special. and it.

and also sad to um. you know to me at least it's kind of. i don't think i'm using too strong of a. ward but it's kind of terrifying the. uncertainty of it. the mystery of it you know the mystery. of death the mystery of it yeah of death. when we're talking about the mystery of. black holes that's somehow distant. that's somehow out there and the mystery. of our own but but but even life the. mystery of consciousness i find uh. so hard to deal with too.

i mean it's not as painful i mean we're. conscious but the whole magic of life if. we can understand but consciousness. where we can actually think and. so forth it's pretty it's such it seems. like such a beautiful gift that it. really sucks that uh we get to let go of. it we'll have to let go of it yeah what. do you hope your legacy is. as i'm sure they will uh aliens when. they visit and humans have destroyed all. of uh human civilization aliens read. about you and encyclopedia they will.

leave behind what do you hope it says. well i would i would hope they. if to the extent that they evaluated me. uh felt that i helped move science. forward as a. tangible contribution and that. i served as a good role model for. how humans should live their lives. and we're part of creating one of the. most incredible things. humans have ever created.

so yes there's the science that's the. fermi thing right yeah uh the instrument. i guess and the instrument the. instrument is a magical creation not. just by a human by a collection of. humans the collaboration. is um. that's. that's humanity at his best. i i do hope. i do hope will last quite a bit longer. but if we don't.

this is a good thing to remember humans. by. at least they built that thing. that's pretty impressive. barry this is an amazing conversation. thank you so much for wasting your time. and explaining uh so many things so well. i appreciate your time today thank you. thanks for listening to this. conversation with barry barish to. support this podcast please check out. our sponsors in the description. and now let me leave you some words from. werner heisenberg a theoretical.

physicist and one of the key pioneers of. quantum mechanics. not only is the universe. stranger than we think. it is stranger than we can think. thank you for listening and hope to see. you next time. you.