Latest / From First Principles / AI Supercharges CRISPR & LIGO (Nobel Prize Week Preview) (EP. 10)
Transcript
- 0:00Hello, Internet.
- 0:00This is your captain speaking, Lester Nare, joined as always by my co-host and our resident PhD, Krishna Chowdhury.
- 0:08This is From First Principles.
- 0:11We have an exciting episode.
- 0:12It'll be a little bit of a special episode this week as we gear up for Nobel Prize Week, which is going to be our episode next week.
- 0:19We're going to do full coverage online.
- 0:21all week long, all three days, detailed deep dives.
- 0:25So be sure to subscribe to catch our Nobel Prize Week coverage.
- 0:28But in advance of that, we wanted to cover two of our favorite recent Nobel Prizes in a little bit of a grab bag of coverage that is anchored by two new papers about how AI is being used for these two fundamental discoveries that got the Nobel.
- 0:47The first of which is going to be how
- 0:50AI-powered CRISPR could possibly lead to faster gene therapies.
- 0:54This is out of Stanford Medicine.
- 0:56And they put their paper in Nature.
- 0:58And then the second story is going to be about LIGO.
- 1:01Again, how can we apply new algorithms to hush the noise, which may lead to more black hole discoveries.
- 1:07This is out of our favorite Caltech, The Legends.
- 1:11And it was published in Science.
- 1:12So this is going to be a great prep episode for Nobel Prize Week.
- 1:16You're going to love it.
- 1:17This is From First Principles.
- 1:35my friend how's it going episode 10 we've made it to double digits double digits baby thanks for everyone who's tuned in we're also on double digits on instagram and tiktok it's it's just get us there on youtube though yes yeah we are on youtube so definitely check us out on youtube if you're not watching this on youtube uh we really appreciate all all the support i think people really like science content yeah uh
- 1:59We do have Nobel Prize Week coming up next week.
- 2:02That's going to be huge.
- 2:03You're going to get so much content from us.
- 2:06We know you guys like the history and the current, so we're going to be combining both.
- 2:10But this week, in preparation...
- 2:14We're going to talk about CRISPR and LIGO.
- 2:16Yeah.
- 2:17Two of our favorite recent Nobel Prizes, let's say, in the last 10 years.
- 2:21Yep.
- 2:22And our first story comes out of Stanford Medicine.
- 2:26And this is related to their new CRISPR-GPT, a large language model that is accelerating gene editing processes and increasing accessibility to CRISPR.
- 2:39So we've talked about CRISPR, CRISPR-Cas9 on the podcast quite a bit.
- 2:43Yeah.
- 2:44And... Yeah.
- 2:45And this one is like, it's an AI co-pilot.
- 2:48Yes.
- 2:49For CRISPR.
- 2:50For gene editing.
- 2:51For CRISPR researchers.
- 2:52It's like, you know how like, you know, all the coders out there probably know about co-pilot.
- 2:58Yes.
- 2:59And you can just like verbally tell it what to...
- 3:03code and then it'll just code it.
- 3:05This is our favorite new term, vibe coding.
- 3:08Vibe coding, yeah.
- 3:09Now you can vibe code with CRISPR research.
- 3:12Okay, it sounds funny, but it's actually going to be really, really good for the scientific community and for the medical community in terms of
- 3:20finding new therapies, all sorts of stuff.
- 3:23It's very cool.
- 3:24Vibe gene editing.
- 3:26Yeah.
- 3:28And so we talked in previous episodes, you made this kind of reference to this idea of like a bacterial immune system as a way to think about CRISPR.
- 3:40That's how it started, yeah.
- 3:42And so, help me, can you like re-explain like what you meant by that as we kind of talk about this combination of AI and CRISPR?
- 3:51Yeah, I mean, you know, in preparation for Nobel Prize Week, I think it's fitting that we talk about the Nobel Prize winners and how they got that discovery and how they got there.
- 4:00And it's an incredible story of like...
- 4:05collaboration in science and also in curiosity-driven research, not application-driven research.
- 4:14Right?
- 4:14Because CRISPR now, obviously, it has so many applications, therapeutic, agricultural, all of these other things.
- 4:21But, you know, it really started off as a curiosity-driven scientific research program.
- 4:29So let's briefly start with what the new paper is about, and then we can sort of tell the story about how we got here.
- 4:38Okay.
- 4:38So the new paper is basically taking this pretty mature technology, which is CRISPR-Cas9, which is this ability for us to snipe and cut DNA at wherever we want.
- 4:52And it's taking that technology and it's –
- 4:57it's training in AI to do that technology, and then it's letting all of these researchers who might be novices in the technology but want to use it,
- 5:08Have a helping hand.
- 5:09And that's where this co-pilot thing comes in.
- 5:11It's like I can, as a researcher, speak in my natural language.
- 5:16And it will then convert that natural language into sort of the technical implementation.
- 5:21Yeah, yeah, exactly.
- 5:23And that's what that current paper that came out in Nature Biomedical Engineering is doing.
- 5:30Yes, yes.
- 5:31And so how did we get here?
- 5:33Yeah.
- 5:34The question is, how did we get here?
- 5:35Because this is crazy.
- 5:37We're playing God at this point.
- 5:38We're playing God at this point, and Christopher lets us play God, right?
- 5:41And I think it's nice to see how it gets there and what the human stories are.
- 5:48So we're actually going to start back in 1987.
- 5:50Ooh, good year.
- 5:53Why is that a good year?
- 5:54I don't know.
- 5:55Oh, okay.
- 5:56The 80s, baby.
- 5:57The 80s.
- 5:57Everything was good in the 80s.
- 5:58That's what they say.
- 5:59Everything was good in the 80s.
- 6:00That's what they say.
- 6:01Yeah, we were winning in the Cold War.
- 6:03Yeah, that's true.
- 6:04That's true.
- 6:05Ronald Reagan was president.
- 6:06Look, look.
- 6:07So everyone was like, it was fine.
- 6:10Take one for the Gipper.
- 6:13Even though he had Alzheimer's at the time, whatever.
- 6:16In 1987, he had full-blown Alzheimer's at the time.
- 6:18Well, he shouldn't have used Tylenol because that's probably the reason why he had that.
- 6:21Yeah, yeah, yeah.
- 6:22It's a whole other story.
- 6:23Turns out, turns out.
- 6:26Anyways, 1987.
- 6:27Okay.
- 6:28Okay.
- 6:29Gene editing is not a thing, really.
- 6:32Okay.
- 6:32Right.
- 6:33There are these things called restriction enzymes, restriction endonucleases.
- 6:38And what they do is they target a specific...
- 6:43motif of DNA, so a specific sequence, and whenever you have that specific sequence, it'll go in and cut it.
- 6:51Okay?
- 6:52The problem with that is it requires that specific sequence.
- 6:55Okay?
- 6:56So it was really in its nascent state at the time.
- 7:03And in 1987, some scientists in Japan, led by Yoshizumi Isshoni, okay?
- 7:12I'm going to say that again because that was wrong.
- 7:15It was Yoshizumi Ishinou.
- 7:19I got the vowels mixed up there.
- 7:21But in 1987, he discovered this segment of DNA in E. coli.
- 7:27E. coli is sort of the bread and butter of biomedical research.
- 7:30Yes.
- 7:31At least when it comes to, you know...
- 7:34this sort of researching bacteria as a model organism to try to understand just basic molecular biology.
- 7:42E. coli is like the goat for that kind of stuff.
- 7:46And what he noticed was, he was sequencing parts of the E. coli genome.
- 7:50At that point, you didn't really have the technology to sequence the whole thing.
- 7:54Now, obviously we have the whole E. coli genome.
- 7:56But back then he noticed that there was this part of the genome
- 8:02That had a very weird structure.
- 8:05Okay.
- 8:06What it had was it had these repeating sequences.
- 8:09Okay.
- 8:10And in between these repeating sequences were non-repeating unique sequences.
- 8:17Okay.
- 8:17So it was kind of like there was like A, which is the repeating.
- 8:21And there would be A, B, and then A, C, and then A, D, and then A, E, and so on and so forth.
- 8:28And each of these parts were about 30 base pairs long.
- 8:31It was very weird.
- 8:33Highly structured.
- 8:34The A was always the same.
- 8:37And at this point, this is very new research where we're starting to sequence large parts of genomes of organisms.
- 8:46And whenever you find this kind of nice mathematical repeating structure, it always like raises flags.
- 8:52Right.
- 8:53Right.
- 8:54So this guy, he publishes a paper in 1987 where he's like, you know, I find these consistently repeating segments and then with non-repeating segments.
- 9:04And everyone started focusing on the repeating segment because that's the part that gets highest signal.
- 9:09Whenever you're doing any kind of thingy on the genome, you're going to get some signal on how much of a match you're getting.
- 9:18And the repeating part is getting this higher signal.
- 9:20So the repeating part is kind of crazy because...
- 9:23It's also a palindrome.
- 9:25You know what a palindrome is?
- 9:27Yes.
- 9:27It's like a race car.
- 9:28Yes.
- 9:29Race car is a palindrome because you read it front or from the back.
- 9:33It's the same thing.
- 9:34Yep.
- 9:34Well, the same thing was happening with these repeats.
- 9:37Okay.
- 9:37Interesting.
- 9:37These repeats had...
- 9:40If you, you know, DNA is double-stranded.
- 9:42Yes.
- 9:42So there's a top segment, for example, and then there's a bottom segment.
- 9:46Yes.
- 9:46And the top segment you'll read from left to right.
- 9:49Yes.
- 9:49That's what they call from the three prime to the five prime.
- 9:52And that'll be, you know, some sequence of ACTGs.
- 9:56But if you read the bottom segment from the other way, it'll be the same exact thing.
- 10:02So it's already like, not only is it repeating and has this highly conserved structure.
- 10:07Yes.
- 10:07Yes.
- 10:07But it's also within the repeats, there's this structure.
- 10:11It's this palindromatic structure.
- 10:13Yeah, yeah, yeah.
- 10:14And it's already, so already it's like, you know, E. coli.
- 10:17Yeah, yeah, yeah.
- 10:18E. coli has this.
- 10:19It's like, that's crazy.
- 10:20Yeah, right.
- 10:21And people thought it was interesting, but didn't really think anything of it.
- 10:27Okay.
- 10:29Then came Francisco Mojica from Spain.
- 10:33Mm-hmm.
- 10:34This is back when bioinformatics was just a nascent field and people had, you know, started to sequence not just E. coli, but they were starting to sequence viruses.
- 10:46Specifically, these things called bacteriophages.
- 10:49Have you ever heard of these things?
- 10:50Yes.
- 10:50Yes, I remember from my...
- 10:51They do.
- 10:52They look like alien motherships.
- 10:54Yeah, with these little, like, long, fatty long legs.
- 10:56Exactly.
- 10:57Like, they look like the Martians that come down and try to...
- 11:02But they're at the molecular level.
- 11:04It's just like the aliens in War of the Worlds.
- 11:07Exactly.
- 11:07When they come down, they look very similar to that.
- 11:09Exactly.
- 11:10Bacteriophages look exactly like that.
- 11:12They've got this capsule, which is this really nice polygon, and that has the DNA material, and then it's got the neck or the shaft, and then it's got these prongs, these legs that attach to the bacteria.
- 11:24Yes.
- 11:25And they're viruses that attack bacteria, hence bacteriophage.
- 11:29People started...
- 11:32finding the DNA sequences of the stuff that's inside bacteriophages.
- 11:35And what they noticed, Francisco Mojica specifically, what he noticed was the stuff that people weren't thinking about in CRISPR, which are, you've got the repeats, the A, A, A, A, but you also have these B, C, D, which has low signal.
- 11:52Those interspaced unique parts were exactly the same DNA that,
- 12:00as the stuff that we were finding in bacteriophages.
- 12:04Okay?
- 12:04So now it's like, and he comes up with this really cool hypothesis, which is that CRISPR, which, okay, I'm not going to say CRISPR because right now we don't have the acronym yet, historically.
- 12:17Sure.
- 12:18But what he comes up with is he says this segment of DNA, of this A, B, A, C, A, D,
- 12:24This is some type of bacterial immune system.
- 12:27Okay.
- 12:27Because how does our immune system work?
- 12:29Okay.
- 12:31We get struck with a virus.
- 12:32Let's say the flu or the COVID or whatever.
- 12:34Right?
- 12:35The COVID.
- 12:35The COVID.
- 12:36Yeah.
- 12:37What ends up happening is you've got these T cells, which create antigens.
- 12:44No, they create antibodies that try to bind to the antigens of whatever pathogen that comes in.
- 12:51And the way that our adaptive immune system works is the T cells create these...
- 12:58sort of antibodies that try to match with the antigens.
- 13:03This is the lock and key.
- 13:04Exactly.
- 13:05It's the lock and key where the antigen has a specific key or specific lock.
- 13:10We try to make the key that fits and the ones that get the right fit, those are the ones that actually proliferate and create more of themselves.
- 13:17You have the sort of mini evolution that goes on within your body to try and remember the
- 13:24the stuff that came in so the next time it comes in you can be ready and you don't have to have a fever it can immediately recognize that pathogen and kill it yes right it can tag it and then other stuff comes in and kills it yes okay so that's this adaptive immune system that we have as humans yes so mojica had this crazy idea of what if we had an adaptive immune system for bacteria where this is a way because obviously you've got these dna segments right that are
- 13:54natively found in viruses but now you're you you've got a memory mechanism yes where you're keeping track of the stuff that you maybe saw in the past in your own dna and maybe maybe that serves as a kind of template where you can compare it to stuff that comes in and be like that's bad yes i'm gonna get rid of that yes okay so so he had this idea that it's a bacterial immune system
- 14:19This A-B-A-C-A-B.
- 14:20This repeating pattern that we are seeing that has repeating components interspersed with non-repeating components.
- 14:28Yes, exactly.
- 14:29And he was like, you know, the fact that they match means that this is some kind of adaptive immune system.
- 14:35Funny story, though.
- 14:36He found this thing in 2001, and he tried to get it published.
- 14:40All the big ones, nature, science.
- 14:42We always talk about nature and science papers.
- 14:44All rejected him.
- 14:45Oh, my goodness.
- 14:45Because it was either like you're wrong or like bioinformatics was so new.
- 14:50It's like you're probably – I don't care.
- 14:52We don't have enough of you.
- 14:53Yeah, so he finally published in 2005 in a journal that's way lower tier than Nature and Science.
- 14:59But it's a fundamental discovery because –
- 15:02That's what led to all of this CRISPR research.
- 15:04With this little insight.
- 15:06Yeah, it's a little insight into, okay, the fact that this matches and the fact that the bacteria keeps track of this, like why would it keep track of this unless it was for remembering the stuff in the past, right?
- 15:19And making sure that it doesn't get duped again, right?
- 15:23And now we know actually that it is a bacterial immune system.
- 15:27What ends up happening is,
- 15:28You know, you have a pathogen, let's say, that comes in and it infects a population of E. coli.
- 15:3499% of them are going to die.
- 15:37In fact, only one in a million are going to survive.
- 15:40But that one in a million that's going to survive is going to be like, that was awful.
- 15:45I don't want that again.
- 15:47So it's going to take – it's going to take – like after it survives, it's going to take whatever part of the viral genome that is left and it's going to integrate it into this A, B, A, C, A, D. Now it's going to make it A, E or A, F. It's A.
- 16:00Adding to this chain of history of next time you see, we've added this new component part so we know what to do.
- 16:07We have that lock and key mechanism in order to, it's like the self-defense piece.
- 16:10Yeah, it's like now I can be like, oh, this matches with you.
- 16:13That means you are not me.
- 16:16Bad guy.
- 16:17Which means you're a bad guy, right?
- 16:18Where's your citizenship?
- 16:20You don't belong here.
- 16:21Exactly.
- 16:22And you have to remember, like, in biology, especially with E. coli, right, they don't have eyes.
- 16:27They don't have, like, reading mechanisms, right?
- 16:30So the way that, you know, at a molecular level, you can actually sense whether something is different and whether something requires...
- 16:42intervention is to actually have a template of DNA that matches the thing that you're trying to get rid of.
- 16:51Yes.
- 16:52Yes.
- 16:52Right?
- 16:53The idea is the lack of a sensory system.
- 16:55Yeah.
- 16:56This is their sensory system.
- 16:57This is their – it's memorializing in the DNA layer because they don't have sight, smell, hearing, touch.
- 17:05This is what they got.
- 17:06Yes.
- 17:06Right?
- 17:07It's like if I recognize, then it can create a cascade of other –
- 17:11processes that then takes care of that 100% right which is which is kind of which is kind of cool to even think about so now francisco mojica establishes that this thing is a bacterial immune system and this is around where we start getting the acronym crispar okay okay um or crisper sorry guys um someone's gonna yeah we've got enough comments about it someone's gonna say something but crisper stands for clustered
- 17:38Because it's clustered.
- 17:39It's all in the same genetic locus.
- 17:41Okay.
- 17:42Regularly interspaced.
- 17:44Yeah, because of that spacing.
- 17:45Because of the regular interspacing.
- 17:46Yes.
- 17:48Short palindromic repeats.
- 17:51Which is literally what you just described.
- 17:52Yes.
- 17:53Which is the idea that the A, which is the part that's repeating, is palindromic.
- 17:57Yes.
- 17:57So it's regularly interspaced and it's interspaced with these viral genomes.
- 18:02And it's short.
- 18:03Yeah, it's short.
- 18:04It's only about 30 base pairs.
- 18:06Yep.
- 18:06Right?
- 18:07Yep.
- 18:07Yep.
- 18:07So...
- 18:08That's sort of how CRISPR is established.
- 18:11And CRISPR is really this bacterial part.
- 18:13Conceptually, this is the birth, this is the origin of the idea.
- 18:18Yeah, and when people say CRISPR, what they really mean is CRISPR-Cas9 or Cas13 or Cas any of these other...
- 18:26Yes.
- 18:27technologies.
- 18:28And the CAS9, the CAS13 part, that's where our two heroes come in.
- 18:33Got it.
- 18:35Emmanuel Charpentier and Jennifer Doudna.
- 18:39Doudna.
- 18:41So this is interesting.
- 18:43Does that make sense?
- 18:44It does make sense.
- 18:47There's a whole... We'll get to it in a moment, but yes, I'm tracking.
- 18:51Yeah, you're tracking so far.
- 18:52So...
- 18:54Now let's talk about our two Nobel Prize winners.
- 18:58Yes.
- 18:59So we got Emmanuel Charpentier.
- 19:01Yes.
- 19:01So she did her PhD at the Louis Pasteur Institute in Paris, founded in the late 1800s by Louis Pasteur himself.
- 19:11You know, one of the foremost...
- 19:14Yeah.
- 19:36So it must just be like, you know, it just sprouts.
- 19:40And now we're like, like, it's like, it's like, that's so stupid.
- 19:43But like back then, I mean, you know, the observation is I let out rotting food and now there's randomly there's flies.
- 19:49Right.
- 19:50Right.
- 19:50Right.
- 19:51The amount of experiments that he had to do to actually convince people that it's not that is actually insane.
- 19:59And I think we should do a separate episode on that.
- 20:01This is people forget that it takes a very long time for new ideas that come from sort of scientific research to actually permeate and settle in the zeitgeist.
- 20:12And in most cases, it is...
- 20:15very aggressively pushed back.
- 20:18Yeah, yeah, yeah.
- 20:20Exactly.
- 20:21And so Louis Pasteur Institute, she gets her PhD.
- 20:25She starts a lab at University of Vienna.
- 20:29And that's where she gets really into studying the Streptococcus pyogenes bacteria, which is a pathogenic bacteria in...
- 20:37It causes tonsillitis, and it's known as a flesh-eating disease because it causes strep throat and it actually starts damaging the soft tissue.
- 20:49And she was really interested in trying to find some way to circumnavigate this pathogen.
- 20:56And while she's working, she actually discovers that there are small RNA molecules that are part of this streptococcus bacterium,
- 21:08that are doing something very close to what the CRISPR sequence is doing.
- 21:13Okay.
- 21:14Okay?
- 21:14They match very closely.
- 21:17And the function, because they match very closely, right, the function should be about the same.
- 21:24Because in biology, the structure means that your three-dimensional structure is about the same, which means you're probably doing the same thing.
- 21:32So she's trying to do this research, right?
- 21:38Doudna.
- 21:39Yes.
- 21:40She actually grew up in Hawaii, did her college in Pomona College, which is... Oh, yeah, it's Sun Street.
- 21:48In Southern California.
- 21:50And, you know, thank goodness for her French professor.
- 21:53Okay.
- 21:53Because...
- 21:55She was majoring in chemistry, and it was getting hard, as science gets hard.
- 22:00It does sometimes.
- 22:01Science gets hard.
- 22:03And she went to a French professor, and she was talking about, you know, maybe switching her major from chemistry to French.
- 22:09And her French professor was like, no, no, no, no.
- 22:14Which is pretty awesome.
- 22:15Shout out to Jean-Brun Doudna's French professor.
- 22:18Thank you.
- 22:19Yeah, shout out to the humanities French professor at Pomona College to be like, no, stick with chemistry.
- 22:24Chemistry is dope.
- 22:25Because that's how we get the Nobel Prize.
- 22:27Yes.
- 22:28And so she stuck with chemistry.
- 22:31She did her PhD with...
- 22:34the Harvard Medical School professor, Jack Sostak, who also won a Nobel Prize in 2009 for his research in telomeres, which is the stuff that...
- 22:49It's at the end of chromosomes.
- 22:50Yes.
- 22:51It's at the end of your DNA, basically.
- 22:53There's a bunch of repeating AT-AT-AT-AT-AT-AT that just goes on forever.
- 22:58And that's basically a way to...
- 23:01circumnavigate the fact that when you age, your DNA gets shorter and shorter.
- 23:05It's a little buffer.
- 23:06Yeah, it's a little buffer.
- 23:07It's a bunch of nonsense DNA.
- 23:09Not really nonsense because obviously it's got functions, but it's a bunch of stuff that doesn't really code for anything to secure the stuff in the middle, right?
- 23:17It's like when you're copying stuff, the stuff at the very ends is going to get wrecked.
- 23:21Right.
- 23:22So you want to have a giant buffer.
- 23:23Yes.
- 23:24So he was really instrumental in that kind of research.
- 23:28She did her...
- 23:30research, PhD research under this guy.
- 23:34Yes.
- 23:35And she was really interested in RNA interference.
- 23:39Okay.
- 23:39Which is this idea of like small types of RNA actually interfering with DNA and influencing gene expression, shutting stuff down, things like that.
- 23:50So she's already in this sort of...
- 23:52molecular biology mindset.
- 23:53The idea is that there's these cases where this RNA is almost acting like a mechanic of some kind.
- 23:59It's coming in, house cleaning, moving stuff around.
- 24:04Yeah, and this was brand new research back in the day.
- 24:06They'd all been...
- 24:10grown up in the days of the central dogma.
- 24:13Right.
- 24:14Right.
- 24:14DNA makes RNA makes protein.
- 24:16Yes.
- 24:17And the RNA is just a messenger.
- 24:19Yes.
- 24:19That is an intermediate between the DNA that's inside the nucleus and the part that makes the protein, which is the ribosome, which is outside the nucleus.
- 24:26So this RNA becomes a messenger.
- 24:29But she was sort of growing up in her academic career at the time when RNA was finding all of these new uses that people had...
- 24:38Not really tried to figure out before.
- 24:40It's not simply that RNA is a translator and a transporter.
- 24:45It has active function within the cell.
- 24:48So she's researching RNA interference at the time.
- 24:53She's at Yale at the time.
- 24:54Boo.
- 24:55Yeah, Boo Yale.
- 24:57She ditched Yale.
- 24:58Good.
- 24:59She ditched Yale for Cal Berkeley because Berkeley solved the two-body problem.
- 25:04Yeah.
- 25:04Do you know about the famous two-body problem in academics?
- 25:07Yes.
- 25:07It's basically you're married, your spouse is an academic, and it's one of the toughest problems to solve in academia, the two-body problem.
- 25:17But Berkeley solved it by hiring both her husband and her.
- 25:21And good for them.
- 25:22Yeah.
- 25:23You know?
- 25:24They are winning.
- 25:26So they switched to Cal Berkeley in the, I think, early 2000s.
- 25:32Very good choice.
- 25:33Good choice.
- 25:34I think they also liked the fact that, you know, Berkeley compared to the Eastern institutions, which we went to one of them.
- 25:40Yes.
- 25:41The Eastern institutions are very formal, if I may say, right?
- 25:45They're very...
- 25:46You know, formal.
- 25:49Upright and straight.
- 25:51Yes, upright.
- 25:51They've got something in there.
- 25:55But, you know, in California, we're a little bit laid back.
- 25:58Yeah.
- 25:59And they liked that.
- 26:00And so they came to California.
- 26:03And that's where...
- 26:06Jennifer Dodna first encountered CRISPR.
- 26:09Okay.
- 26:09Okay.
- 26:10She had a brief sojourn into actually private tech.
- 26:15So she worked for Genentech, which is this company.
- 26:18It's a big company.
- 26:19She worked for Genentech.
- 26:20She wanted to see what private industry research would be like.
- 26:25She lasted two months.
- 26:27She wrote this article about her, and it was just like, no.
- 26:30No.
- 26:31this thing for me.
- 26:32But because she had left, right?
- 26:34She had sort of left all of her teaching and administrative obligations behind.
- 26:41So when she came back, she could just focus fully on her research.
- 26:44Freedom!
- 26:45Right?
- 26:45Freedom.
- 26:45Freedom.
- 26:46And this is when one of her colleagues, Jillian Banfield, contacted her.
- 26:51Jillian Banfield was a professor at Berkeley.
- 26:54Mm-hmm.
- 26:55She was working with trying to sequence sort of the metagenomes of samples.
- 27:01So she'd go to like mines and try to collect bacteria there, or like thermophils and try to collect bacteria there, soil samples, and try to do a metagenomic analysis where you sequence a bunch of genomes and you try to find, you know, stuff in the genome.
- 27:19Okay.
- 27:20And what she had noticed was, and this is something that was in the literature as well,
- 27:25You kept coming up with this CRISPR sequence.
- 27:28Okay?
- 27:28She found it in bacteria in the mines.
- 27:31She found it in bacteria here, there.
- 27:33Not only did she find it in bacteria, she also found it in archaea, which is kind of like bacteria.
- 27:39They're, you know, sort of indistinguishable from bacteria if you look at it.
- 27:44in a microscope.
- 27:44They kind of look like bacteria, single-celled organisms.
- 27:47But if you look at the phylogenetic tree of life, you know, where you have some primordial first-life ancestor and then that fans out, one of the first two things that fanned out was actually bacteria and archaea.
- 28:02And then from bacteria outcrop the eukarya, which is us.
- 28:07Eukaryotes are the multicellular organisms that have mitochondria living in them and chloroplasts living in them and a nucleus living in them.
- 28:15The powerhouse of the cell.
- 28:16Yes.
- 28:17And all of these.
- 28:17So the higher complex organisms came out of the bacteria.
- 28:21But very early on.
- 28:23In the evolution of life came out bacteria and archaea.
- 28:27And the fact that the CRISPR sequence exists in both bacteria and archaea is very, very interesting.
- 28:35Because this means this happened very, very early evolutionarily.
- 28:38Very, very, very early.
- 28:39It says two things.
- 28:40One is viruses were around like...
- 28:43Even back then, viruses were like, ooh, I got to get in on that.
- 28:47Yeah, yeah, yeah.
- 28:48And the other thing is this thing is preserved, which means it really might have this immune capability.
- 28:54And it might be nice to figure out how it works.
- 28:57Yes.
- 28:57Yes.
- 28:58Now, Jillian Banfield at Berkeley, she thought it was something to do with RNA interference.
- 29:03Okay.
- 29:03It's some kind of interference mechanism where it creates an RNA and then that RNA interferes with these viral DNA to sort of stop it from happening.
- 29:13Yes.
- 29:13So what she literally did was she Googled RNAi Berkeley.
- 29:18Okay.
- 29:19And out pops Jennifer Doudna's DNA.
- 29:23Yeah.
- 29:24Right?
- 29:24Yeah.
- 29:24She's like, okay, this is someone who works in R&AI.
- 29:27It's at Berkeley.
- 29:28So, gives them a call.
- 29:30Yes.
- 29:32And they set up a meet cute at the cafe, which is the free speech movement cafe in Berkeley.
- 29:39Yes.
- 29:39Yes.
- 29:39Very famous.
- 29:40It's a cafe in one of the libraries in Berkeley.
- 29:44It commemorates the free speech movement back in the 1960s and 70s.
- 29:48A movement we are trying to reinvigorate here in the United States.
- 29:51Yeah, it's probably like...
- 29:55On its high tails right now, right?
- 29:57We really need that.
- 29:58But they met at this free speech movement cafe.
- 30:01Yes.
- 30:01They have a little bit of banter.
- 30:02And then Jillian Banfield gets right into CRISPR.
- 30:05It's like, this is what CRISPR is.
- 30:07It's kind of crazy.
- 30:08Jennifer Doudna is like immediately hooked.
- 30:11Yes.
- 30:12Like, this is crazy.
- 30:13Yeah.
- 30:13Right?
- 30:13Yes.
- 30:13Palindromic.
- 30:15Yeah.
- 30:15Regularly interspaced.
- 30:16Because people had seen these sort of regular structures before or these palindromic structures before, but not in this sort of nice...
- 30:26like organized form.
- 30:28It was too perfect.
- 30:29It was too perfect for it to be just some random thing.
- 30:32Yes.
- 30:33Okay?
- 30:33Yes.
- 30:33So that's when Jennifer Doudna starts thinking about CRISPR.
- 30:38Okay?
- 30:39And she starts investigating the CRISPR system.
- 30:41She starts mapping it.
- 30:43And what, at the time, people end up finding is...
- 30:46There's the CRISPR part of the genome, which is this A, B, A, C, A, D. And then there's another part of the genome that's always there right next to it.
- 30:55Okay?
- 30:55We talked about how promoters are right next to the part of the genome.
- 30:58Yes.
- 30:59So this is kind of like that.
- 31:00It's not a promoter, but it was an associated region because it would always be there right next to the CRISPR system.
- 31:08It was a crony.
- 31:09It always hung out.
- 31:09It would always be hanging out right before.
- 31:12They started calling it CRISPR-associated.
- 31:16And it became Cas.
- 31:17So now we're getting CRISPR-Cas.
- 31:21So the CRISPR is that regularly repeating interspace sequence.
- 31:27And then the crony that's always with the little mob boss.
- 31:32That's the Cas.
- 31:33That's the CRISPR associate.
- 31:35Yes, and it becomes the Cas.
- 31:37Yes, that becomes where Cas and CRISPR-Cas9 sort of...
- 31:42Okay, I'm trying.
- 31:43So now we've got to get to the 9.
- 31:44Yes.
- 31:44Because we've already fixed the puzzle with CRISPR.
- 31:47Yes.
- 31:47We fixed Cas.
- 31:48Yes.
- 31:49Now we've got to get to the 9.
- 31:50Right.
- 31:51This bacterial immune system and this associate of that sort of immune system structure.
- 31:59Okay, yes.
- 32:01So she starts researching these Cas systems.
- 32:06It turns out there's two types.
- 32:07There's a class one system, and that requires many different proteins to function.
- 32:12They'd figure that out.
- 32:13And then there's a class two system that was sort of simpler.
- 32:16Okay.
- 32:17Now let's get back to Emmanuel Charpentier.
- 32:19Yes.
- 32:20Okay.
- 32:20So meanwhile, while Doudna is doing this in her lab...
- 32:24Sharpeian TA starts looking at the streptococcus genome.
- 32:27Yes, the soft tissue eating.
- 32:30And she starts... Yeah, the soft tissue streptococcus tensilitis causing bacteria.
- 32:36And she starts discovering a previously unknown RNA molecule that was very closely associated with CRISPR.
- 32:44Okay?
- 32:44And she called it the tracker RNA for trans-activating CRISPR RNA.
- 32:49It's something that was required for...
- 32:53the CRISPR RNA, which is the RNA that is made from transcribing the CRISPR DNA, right?
- 32:59CRISPR, remember this ABA, ACAD thing.
- 33:03Yes.
- 33:03This is in the DNA.
- 33:04Yes.
- 33:05But that gets transcribed by RNA polymerase to become an RNA molecule.
- 33:09Yes.
- 33:09Right.
- 33:09And then that RNA molecule, presumably for all the other gene stuff, that RNA molecule goes outside and makes a protein.
- 33:15But in this case, what it was doing was it's mediating this immune system.
- 33:19Okay.
- 33:20And what she realized was there's this other,
- 33:23RNA molecule called tracker RNA that is required to make that bigger CRISPR RNA work.
- 33:29Got it.
- 33:30And do its thing.
- 33:31Okay.
- 33:32Okay.
- 33:32So she starts looking at this tracker RNA and she's like, okay, this thing is essential for making whatever CRISPR is doing work.
- 33:42She publishes that in 2011.
- 33:43Okay.
- 33:44Got it.
- 33:44Okay.
- 33:46And then we have the chance meeting in Puerto Rico.
- 33:49Ah, look.
- 33:49Great, great.
- 33:50In San Juan, Puerto Rico.
- 33:51In the U.S.
- 33:53In the U.S.
- 33:56They meet at a conference, and they get introduced to each other with one of Doudna's colleagues.
- 34:04They have a short meet-cute, and then they decide to...
- 34:10explore the city together, the old San Juan city together the next day.
- 34:15And on this walk in the old San Juan city, they talk about what they've been working on.
- 34:21And Sharpen TA says, okay, why don't we collaborate?
- 34:24Because you're a biochemist.
- 34:25I'm sort of the structural person who does bacterial research.
- 34:29Perhaps we can help each other.
- 34:33They agree.
- 34:35And so Jennifer Doudna now, they start like...
- 34:38collaborating via Skype and their postdocs start collaborating.
- 34:42RIP Skype recently shut down.
- 34:44Yeah, yeah.
- 34:44Now it's called Zoom, but I guess I still use Skype.
- 34:46That just shows how old I am.
- 34:49But they start collaborating on the interweb.
- 34:52Yes.
- 34:53And –
- 34:56They start focusing on a class 2 system.
- 34:59Remember, Doudna was focused on class 1.
- 35:01The more complex.
- 35:02Charpentier is like, no, no, I got a class 2.
- 35:04Yeah, yeah.
- 35:04It's quite nice.
- 35:05Yes.
- 35:07It's this thing in the streptococcus, and it requires only a single protein, not the multiple that you need.
- 35:13And the single protein, they're calling it Cas9.
- 35:16Mm-hmm.
- 35:17I see.
- 35:19So now we're getting to Cas9.
- 35:20It's the ninth associate.
- 35:21It's the ninth associate.
- 35:23It's sort of named on the...
- 35:26the order in which it was discovered.
- 35:28Which makes sense.
- 35:29So it's CRISPR-Cas9.
- 35:31She's like the single protein that's required.
- 35:33And they suspected that Cas9 was a scissor that cut viral DNA.
- 35:39So what CRISPR would do is CRISPR would be this record of all the viral DNA that the bacteria had seen in its past.
- 35:47It would be like a historical map.
- 35:48Yes.
- 35:49Or in its ancestors' past that had been passed down genetically.
- 35:53And...
- 35:54The Cas9 system would take this, match it to a viral protein, and then cleave it.
- 36:00Yes.
- 36:01Okay?
- 36:01So they did an experiment where they combined the Cas9 protein, they combined the CRISPR RNA, which is the thing that gets transcribed from the ABA-CAD.
- 36:10Yes.
- 36:11And then they combined the target DNA, and they're like, okay, it should work.
- 36:15Didn't work.
- 36:16Okay.
- 36:17Okay?
- 36:17They're like, what the hell?
- 36:18Yes.
- 36:18Okay.
- 36:20And then after a lot of soul searching and everything, Charpentier is like, well, you know, the tracker RNA that I had earlier, I thought it was just doing this job of like preparing the CRISPR RNA for this task.
- 36:35But what if it's like needed for something else?
- 36:37So they put in the tracker RNA.
- 36:39This other thing you were talking about.
- 36:40This other thing that I was talking about.
- 36:41That was sort of just like in the sidelines.
- 36:44Right?
- 36:44In the sidelines.
- 36:45They put in the tracker RNA and all of a sudden,
- 36:48We're getting scissors.
- 36:50Yes.
- 36:51We're getting scissors that are like actually cutting stuff.
- 36:55Yes.
- 36:56They're like, oh, okay.
- 36:58So we got something that cuts.
- 37:00And this is meaningful because still in and around this time, this idea that RNA has this active...
- 37:09like aspect to it is, is in its nature.
- 37:13Like it's still kind of being worked out.
- 37:15Yeah.
- 37:16Like it's not quite obvious.
- 37:18It's not quite obvious that like, that like RNA would be such a huge part.
- 37:23Right.
- 37:23Of the activity of an enzyme.
- 37:25Right.
- 37:25Like Cas9 is a protein.
- 37:27Right.
- 37:27But like it needs this tracker RNA to actually do its job.
- 37:30Yes.
- 37:31Right.
- 37:31And now it gets interesting.
- 37:34Mm-hmm.
- 37:35Because,
- 37:37The way that this Cas9 system is identifying the thing that it needs to cut is through the CRISPR RNA.
- 37:45Right.
- 37:47But the next question is, what if I just make the CRISPR RNA whatever I want?
- 37:53So, okay.
- 37:54And now that is the key insight.
- 37:57We've discovered that CRISPR is this repeating pattern that's kind of this historical map of past interactions that bacteria were having that helped it to remember how to fight back.
- 38:09We have these associates, these cronies, the bag men that go out and kind of do stuff, one of which is Cas9.
- 38:17Yeah.
- 38:17Right?
- 38:18Right?
- 38:19And Cas9 had one job.
- 38:22And that one job was to cut people.
- 38:23Actually cut people.
- 38:24Yeah.
- 38:25Cut them.
- 38:25But how did it know what to cut?
- 38:27Right.
- 38:27Right.
- 38:28And...
- 38:29Could you change its instructions of what to cut?
- 38:33Yeah, because it's almost like, as you say, okay, let's go with the cronies thing, right?
- 38:37Yes, yes.
- 38:37Like the cronies got a photo.
- 38:39Yeah, right, right.
- 38:40Of like who he needs to cut.
- 38:42Yeah, this is who you got to go after.
- 38:44And then he looks around, right?
- 38:46What if I just replace the photo with whatever I want?
- 38:48Yes, put a little deep fake.
- 38:49Yeah, right?
- 38:50Exactly.
- 38:51And that's what they figured, right?
- 38:52That is so fascinating.
- 38:54The first insight was, okay, maybe we can give it.
- 38:59Our own version.
- 39:00We can repeal and replace the initial CRISPR sequence with something else so that Cas9 goes after what we tell it to go after.
- 39:08Yeah.
- 39:09Not what it was maybe historically X, Y, and Z. Yeah.
- 39:11The other thing that they did that was, again, huge and part of the discovery.
- 39:15Because already, this would be a crazy discovery.
- 39:18Yeah.
- 39:19Okay, already the fact that a Cas9 system, what it's doing is it's matching this DNA with whatever DNA that comes in and then it's cutting it out that place.
- 39:26Already that's insane.
- 39:28Yes.
- 39:28Okay.
- 39:29The next thing they did was they noticed that we'll track her RNA.
- 39:32which is the sort of helper that comes in.
- 39:35Yes.
- 39:36Let's say in the crony example, it's the driver.
- 39:38It's the driver, yeah.
- 39:39Which gets, like, just as a loose analogy.
- 39:41Exactly, yeah.
- 39:42It's the driver, right, that comes in.
- 39:45And then you've got the photo.
- 39:47Yes.
- 39:49Which is the thing that lets it recognize, right?
- 39:52These are two separate components.
- 39:53Right, right, which are important.
- 39:55Yeah, which are important.
- 39:57So what they figured was, what if we made them a single component...
- 40:01Oh, okay.
- 40:01Called guide RNA.
- 40:03Okay.
- 40:04This was a big one.
- 40:05Okay.
- 40:05Because what they did, because now it's just way simpler.
- 40:08Anyone in a lab can just make a single piece of guide RNA.
- 40:12It's a single piece of RNA.
- 40:13Yes.
- 40:13That I can just make.
- 40:14Yes.
- 40:15I know how to make RNA.
- 40:16Yes.
- 40:17And I can just make that and be like, this part of the RNA is the thing that I want to cleave.
- 40:20Yes.
- 40:21That's what they did.
- 40:23They combined, they added a nucleotide sequence that sort of stitched these two together.
- 40:28The CRISPR RNA, which is the part that's recognizing what I want to cleave.
- 40:33Yes.
- 40:33And the tracker RNA, which is what's sort of preparing the Cas9 protein to do the cleaving.
- 40:40They combine these into a single thing.
- 40:42And it's not as trivial as just like, oh, I just like staple them together.
- 40:46Because if I staple them together, that's going to change the morphology of them.
- 40:49Yes.
- 40:49And then the Cas9 protein, your crony is not going to be happy.
- 40:52Right.
- 40:52He's going to be like, I don't know what to do with this.
- 40:54I can't recognize this photo.
- 40:55Yes.
- 40:55Right?
- 40:56Yes.
- 40:57They did it in such a way that the tracker RNA part of the structure was intact, and the CRISPR RNA part of the structure was intact, but they were connected together in a way that didn't get in the way of the Cas9.
- 41:11Yes.
- 41:11Yes.
- 41:12That's what they did.
- 41:13They created a guide RNA.
- 41:15So, and again, to continue this really bad analogy, whenever you're trying to commit crimes, you want to minimize the amount of people who are your co-conspirators.
- 41:24Exactly.
- 41:24And so instead of having a driver and then the crony who's doing the cutting... Yeah.
- 41:29You just have the driver and the crony be the same person as one more or less point of failure.
- 41:34And it's hard to find that person that can do both things.
- 41:38And it's hard to make that person and train him.
- 41:41But you got it.
- 41:43That's exactly right.
- 41:44And so that is what became the CRISPR-Cas9 system.
- 41:48Okay.
- 41:48Okay.
- 41:49It's really the guide RNA.
- 41:51That was the sort of key aspect that made it move from an observation of something that's happening naturally to a programmable platform or concept or system that could then effectuate specific instructions dictated by...
- 42:09Yes, very good point.
- 42:10And to that point, in 2012, they published in Science.
- 42:13Yes.
- 42:13And in their abstract, they could already tell this was going to be big.
- 42:16Right.
- 42:16Because they wrote in their abstract that this is an RNA programmable genome editing technology.
- 42:22It's so funny because, I mean, that's immediately what I think of.
- 42:24It's just like, well... You can now...
- 42:27Because before we used to have these things called zinc finger nucleases.
- 42:32Okay.
- 42:32Right?
- 42:32That was the best we could do where you have these like zinc fingered domains of proteins.
- 42:38Yes.
- 42:38That would recognize three nucleotides at a time and then actually like try and cleave stuff.
- 42:44And that was the best we could do with programmable stuff.
- 42:46It was really hard to make, dude.
- 42:48It's really hard.
- 42:50Like, for each zinc finger is, like, attached to three.
- 42:54You got to make, if you want to do a much larger recognition, you got to do three times three times three.
- 42:58And they've got to be the right structure.
- 43:00And, like, making these proteins is really hard.
- 43:02Making RNA is super easy now.
- 43:05Right?
- 43:05Even back then, it was, like, way easier.
- 43:07Which goes to show, like, right after they published this, right?
- 43:10Then there was an MIT group from Feng Zhang who published how to do this with mammalian cells and human cells.
- 43:18And then since then, I mean, the technology has just completely blown up.
- 43:21Yes, 100%.
- 43:23Now we're making crops that can withstand drought.
- 43:27Yes.
- 43:27We've got... Shout out David Freeberg and the All In Boys.
- 43:30Exactly.
- 43:31We've got CRISPR technologies that do...
- 43:37Genome editing in humans.
- 43:40But it's happening.
- 43:42I mean, it's curing sickle cell disease, which is really nice.
- 43:45Big for black people.
- 43:46Yeah.
- 43:46It's also being used by the Chinese.
- 43:51In one instance.
- 43:51I'll give them that.
- 43:52It was one instance.
- 43:53That we know of.
- 43:54That we know of.
- 43:55Yeah.
- 43:55But they literally said they took out a genome that gives...
- 44:02HIV a leg up in trying to infect someone.
- 44:06But no, at the end of the day, you like, you edited the genome of like a human being.
- 44:12And now that human being is out there.
- 44:15You know, like reproducing and stuff.
- 44:16That's kind of crazy.
- 44:17It gets very – Like I did not sign up for that.
- 44:19It gets very messy.
- 44:20But like in any case, like CRISPR – I hope you now see the sort of – 100%.
- 44:24The thread of discovery, right?
- 44:26Where it starts from just curiosity-driven.
- 44:29Yes.
- 44:29What is A, B, A, C, A, D doing in E. coli?
- 44:33Why is it in Archaea?
- 44:34Yes.
- 44:35To now we've got a technology that lets us play God.
- 44:40What's so important about this story, there's so many important aspects of this story, but I think the thing that sticks out for me is a lot of times folks don't understand how a scientist in a lab with an electron microscope or looking at really tiny stuff –
- 44:58They don't get the through line for how that ends up creating something that is going to be one of the most profound scientific discovery terms of impact on medical outcomes for people that we've ever made.
- 45:13I mean, this is like having a programming language with infinite idea space.
- 45:19space yeah yeah yeah for the fundamentals of like what makes us yeah and like it's it is the blueprint we can now edit blueprints of buildings right the buildings are us and the buildings are us it's insane it's it's it's it's insane there's an interesting before we get to
- 45:38The paper.
- 45:39The paper.
- 45:39Because now we've created the base of understanding how did we get to this new paper that's coming out of Stanford Medical.
- 45:48That's right.
- 45:48About creating CRISPR-GPT, which just feels like yoga babble of new thing CRISPR, new thing chat-GPT.
- 45:56Just smash it together.
- 45:57It doesn't actually mean anything.
- 45:58Yeah.
- 45:58But now that we have that background, there's an interesting side story to these characters that you just talked about and touched on at the end.
- 46:08The president of the United States and his good friend Jeffrey Epstein are not the only ones who have suffered from years of long legal battles over who came first.
- 46:19Two of America's most elite research universities have been locked in a legal dispute over who was first to file.
- 46:27Yes.
- 46:27That's file.
- 46:28F-I-L-E.
- 46:30File.
- 46:30And we're talking about patents.
- 46:32Yes.
- 46:32The other P word.
- 46:33We're talking about patents.
- 46:34Yeah.
- 46:34Because whenever you make something big like this.
- 46:37The immediate reaction from people who are capitalistic is like, that's multi-trillion dollar market.
- 46:43Yeah.
- 46:44In terms of personalized medicine, gene editing.
- 46:46I mean, we're talking, it's like at least one or two NVIDIAs.
- 46:50And so just as a brief kind of sidecar to the background you just gave, we talked about this.
- 46:57Let's start at the beginning, which is the discovery.
- 46:59So Doudna and Charpentier, they make this discovery in 2012.
- 47:04Publish it in science.
- 47:05Publish it in science.
- 47:05And then months later in early 2013, Fang Zhang at the Broad Institute at MIT is the one who made the leap to show that CRISPR worked in eukaryotes.
- 47:17Yes.
- 47:17This is the mammalian cells, animal cells, which matters because that's how you can create a product.
- 47:22Right.
- 47:22Yes.
- 47:22Now it becomes something that the health people want.
- 47:26Right.
- 47:26It's not just this observation about our natural environment.
- 47:28You can actually productize it.
- 47:30Yeah.
- 47:30So the idea here is that, you know, Berkeley proved that the tool worked and then the Broads showed that it can work in cells that matter for medicine.
- 47:38Yeah.
- 47:38Yeah.
- 47:38that's when the patent race begins.
- 47:40So it gets a little bit messy.
- 47:42So Berkeley filed their patent application first in May of 2012, covering CRISPR broadly, no pun intended.
- 47:50And then the Broad filed later in December of 2012, so just a couple months apart.
- 47:55But MIT fast-tracked their application with the patent office, which meant they actually got the first CRISPR patent in 2014 covering use in human and animal cells while Berkeley's application was still making its way through.
- 48:11Oh, my gosh.
- 48:11Which is like, okay, okay, okay.
- 48:13So now the first legal challenge, Berkeley challenged that, obviously.
- 48:17So now in 2016, fast-forward two years after MIT got that initial patent for human and animal cells.
- 48:25The patent office held this special interference trial, not to be confused with RNA interference, to decide if the Broad's patent overlapped with Berkeley's patent.
- 48:34And then in 2017, the ruling was a little bit of a surprise where the patent board said both can stand.
- 48:43Both patents can stand.
- 48:45And it was because –
- 48:47They argued that CRISPR moving from a test tube to human cells was not obvious.
- 48:52Like, this is sort of the term I use with patents.
- 48:54Like, is it obvious?
- 48:55Yeah, yeah, yeah.
- 48:55I see.
- 48:56So they were arguing that it's not obvious, and it counted as a separate invention.
- 48:59Okay.
- 49:00So this obviously gave MIT the upper hand for commercial applications.
- 49:05Yeah, yeah, because, like, that's where the big money is.
- 49:07That's where the money is.
- 49:07I mean, sure, you can use it for agricultural stuff, but, like... You know, which is important.
- 49:12Yeah, which is important, yeah.
- 49:14But it didn't end there, not satisfied, right?
- 49:16So round two.
- 49:17Round two.
- 49:18So Berkeley came out with new filings aimed at this eukaryotic cells issue.
- 49:23Right.
- 49:24And they got a second interference case.
- 49:26Now, in 2022...
- 49:30Berkeley lost the claim outright because they were arguing that the Broad hadn't in fact shown that they were able to make it work in human cells, but they were.
- 49:37So it was kind of like, eh, it didn't really...
- 49:40So the loss then had this big financial and reputational hit, because it's like, you're begging now.
- 49:46Right, right.
- 49:47Like, you lost, take your L, take your toys and go home.
- 49:51But, obviously, this is worth hundreds of millions, billions of dollars, licensing fees.
- 49:55So like, you know.
- 49:56Okay.
- 49:58Here's what's interesting, and this goes back to our Nobel Prize discussion.
- 50:01Yeah.
- 50:03In 2020, right, the Nobel Prize ultimately went to... Jennifer Doudman, Emmanuel Chagbite.
- 50:08Chagbite at Berkeley, despite not getting the patent.
- 50:12So the credit for the discovery went to the original founders.
- 50:16That's right.
- 50:17And they didn't, you know, the Nobel Prize Committee could have easily done it for three people.
- 50:22Because the three is the limit, according to Alfred Nobel's will, of how many people can win a Nobel Prize.
- 50:29But they chose to give it to Charpentier and Doudna, right?
- 50:33Which is like, look, the OGs, you were first.
- 50:36I mean, as I was saying, right?
- 50:37It's like patents are, I think, local in time, but Nobel Prizes are forever.
- 50:42Yes.
- 50:42You know?
- 50:43Yes.
- 50:43Unlike diamonds.
- 50:44No, I'm kidding.
- 50:45So there was a split between who got the glory, like the prestige, right, to be immortalized forever.
- 50:51Yeah.
- 50:52And who's going to make their shareholders hundreds of millions of dollars.
- 50:54Exactly.
- 50:54Yeah.
- 50:55So this kind of has shaped the biotech startup playing field in terms of developing CRISPR therapies because you likely had to license it with the Broad Institute.
- 51:06And all of Berkeley's allies were kind of boxed in at least commercially.
- 51:10Yeah.
- 51:10Yeah.
- 51:11Now, just this year, in 2025, this is still ongoing.
- 51:16It is.
- 51:17Because a federal appeals court actually reopened the case.
- 51:22Oh, my God.
- 51:23Saying that the Patent Office may have applied the wrong legal standard back in the 2022 case.
- 51:30So this is not entirely over.
- 51:32Wow, it's not even over.
- 51:33In terms of, you know, who owns CRISPR itself.
- 51:38in human cells.
- 51:39It's still being litigated.
- 51:40And again, I think hundreds of millions and billions is underestimating the total addressable market impact when these gene therapies get to scale, not only in the US and other Western, but globally.
- 51:56So it was just this... Dude, that's crazy.
- 51:59I mean...
- 51:59To think – I don't even know – so all of these people who have been using CRISPR, there's so many companies that have been using CRISPR on the MIT license, right?
- 52:09Let's say for sake of argument that Berkeley wins this appeal in 2025, what's going to – This is – we're going to start our new From First Legal Principles sideshow.
- 52:18Yeah, yeah.
- 52:19No, there's a really interesting point there.
- 52:21Right?
- 52:21It's like – Is it – what are the retroactive remedies for Berkeley saying, look, we've lost out on –
- 52:28existing revenues, it could potentially be a very big landmark case if ultimately Berkeley ends up winning this reopening of the case, which is...
- 52:40I'd love to see MIT just pay Berkeley out of pocket because I just hate MIT.
- 52:46Yeah.
- 52:47Look, we are the best university on the East Coast.
- 52:50They're always chasing us.
- 52:51We get it.
- 52:52We get it.
- 52:52It's hard to be the best all the time.
- 52:54But I mean, to Doudna's credit, though, I saw a...
- 53:00interview of her with dan rather yes back in 2017 back when you know this was at the height of it and um dan rather in his journalistic voice is like i wouldn't be doing my job if it weren't if i wasn't asking about the legal dispute and and she said very very calmly and quite nicely that you know that legal dispute is between the two institutions right mit and berkeley right and
- 53:26Her opinion was that science shouldn't slow down because of a legal dispute.
- 53:31So she was totally for all of these companies using the existing MIT patent to go and forge ahead.
- 53:38You know?
- 53:38Yeah, yeah.
- 53:39Which is how it should be.
- 53:40Which is, I think that was really cool to see that.
- 53:43And in good spirit of it.
- 53:44I think what we all mean when those of us who are passionate about science and research, experimental design and growth of this understanding of the fundamental knowledge of the world around us and applying it in a way that impacts people's lives every day.
- 53:59Yeah.
- 54:00Not to poo-poo on the theorists.
- 54:02We love you too.
- 54:03Yeah.
- 54:04You guys are important.
- 54:05Important.
- 54:05We get it.
- 54:06Practical applications are nice.
- 54:07Yeah.
- 54:07Yeah.
- 54:08And yeah, I thought it was a really cool answer.
- 54:12That's good.
- 54:12No, that's good.
- 54:13Institutions are always going to battle over the dead carcasses.
- 54:16Yeah.
- 54:16So that's kind of how it goes.
- 54:18I mean, to me personally, I think Berkeley won because they got the Nobel.
- 54:22Yeah.
- 54:22you know what what really matters all the now and now she gets a you know at berkeley the tradition is every nobel prize winner gets a really nice parking spot right next to their building look like everybody else has to park in the parking structure and walk yeah but like there's a it says reserved for nobel prize winner oh it's so great just like that she's just like roll up and park right next to it there's a whole studio episode about a parking spot like just this exact same story that's right
- 54:48Yeah, yeah, yeah.
- 54:49But I love that in academic institutions, they're like, no, she wants to know.
- 54:54Yeah, no, she's not going to the garage.
- 54:57What?
- 54:57She's not a peon.
- 54:58Yeah.
- 54:59That's for you PhDs and lab rats.
- 55:03Okay, so we've now, we have a really strong foundational understanding from first principles about what it is, what are we talking about when we say CRISPR-Cas9?
- 55:13Yeah.
- 55:14And kind of the history of how this osmosis and collaborative nature brings us to a point of actual application.
- 55:20So now Stanford Medicine put out this new paper about CRISPR-GPT.
- 55:24Yes.
- 55:24Which is now taking all of this decades, all the way back to 1987 where we started the story of understanding.
- 55:32Yeah.
- 55:32To now applying something that's relatively new in the zeitgeist, large language models, and applying it to this Cas9 use case.
- 55:40So what does that look like?
- 55:41Yeah, so now it's been about 13 years since the discovery of CRISPR-Cas9, and it's been used in a variety of different applications.
- 55:50But at the end of the day, it's actually quite intricate.
- 55:54The whole technology requires intricate decisions.
- 55:58By now we have Cas9, we also have Cas13, we have all of these different associated proteins that you can use in these different use cases.
- 56:06And it's hard for a novice to know which one to use.
- 56:10There's a high failure rate.
- 56:12There's safety concerns.
- 56:14You can get bottlenecked in all sorts of little tiny things that happen in the scientific process.
- 56:20And to actually...
- 56:22Make that better for researchers.
- 56:26Stanford, along with Princeton and Google DeepMind, they actually developed this co-pilot, which is CRISPR-GPT.
- 56:35That's what they're calling it.
- 56:36It's a co-pilot for gene editing experiments where researchers can literally talk to the CRISPR-GPT and be like, you know, I want to use CRISPR on this...
- 56:50human lung cancer cell line, and I want to target these locations.
- 56:55How should I do my experiment?
- 56:56And the GPT will output all of the steps that you should do, how you should design your experiments, what to look out for, how you should analyze the data.
- 57:08All of that, right?
- 57:09It becomes like this sort of lab mate.
- 57:11Yes.
- 57:12That, you know, you wish you had.
- 57:14I wish I had.
- 57:15I was going to say.
- 57:16Back in my PhD days, right?
- 57:18And it can really expedite and democratize the use of CRISPR.
- 57:24Yes.
- 57:25In all of these systems by researchers who might not be totally versed in how to do it in the first place, right?
- 57:33And I think that's really cool.
- 57:35Yes.
- 57:36It was trained – so the training is pretty interesting.
- 57:39It was trained on 4,000 real-world discussion threads.
- 57:43So there was this thing called a CRISPR-focused Google group, which is around 3,000 question and answer sessions with really –
- 57:52Talented CRISPR scientists.
- 57:54And what this GPT did, it was actually a CRISPR Lama 3.
- 57:58So it's based on the Lama 3 from Meta, I believe.
- 58:02And it was a specialized model that was trained on these discussion threads, along with a lot of scientific papers that were out about CRISPR.
- 58:10Lama 3 is old.
- 58:11They could have used... That might have been...
- 58:12Anyway.
- 58:12Yeah, I mean, it was probably like something that they started way back.
- 58:16100%.
- 58:17It's probably something that required, you know, less compute resources and all this other kind of stuff.
- 58:21100%.
- 58:22It's kind of interesting that DeepMind was involved in this, but they still use Lama 3.
- 58:29But the AI was trained on these nuances of scientific discourse.
- 58:34That you don't really get with reading papers.
- 58:38Like you don't get troubleshooting.
- 58:40Right.
- 58:40You don't get problem solving.
- 58:41You don't get like, this is what I tried and it didn't work.
- 58:45That's something that you get in these discussion threads.
- 58:48Yes.
- 58:48Right?
- 58:48So similar to how the normal chat GPT that everyone uses is trained on all of the internet, including all these Reddit threads.
- 58:54Yeah.
- 58:55All we're saying is the training data for this specialized model used a version of a Reddit thread with only very high-level experts that are talking about this outside of the explicitly data-driven or experimental context.
- 59:09It's sort of this gray area, that human element.
- 59:14Yes.
- 59:14And then you get an AI that sort of talks and thinks like a human scientist.
- 59:20It approximates that context.
- 59:22Exactly.
- 59:22Yeah.
- 59:23And they compared it against just, you know, GPT-3.5, GPT-4.0.
- 59:27Because obviously, I mean, I can ask GPT-4.0 about CRISPR and it'll be pretty good.
- 59:33Yes.
- 59:33Is this any better?
- 59:34It's a lot better.
- 59:35Which makes sense.
- 59:36Like when it comes to experiment planning, this was near perfect.
- 59:40Okay.
- 59:41And I've actually tried experiment planning with GPT-40, and it's very, very bad.
- 59:47It's not good.
- 59:48It's a lot of noise in there.
- 59:49Yeah.
- 59:50It's a lot of, like, it's stuff that an undergraduate would, like, come up with.
- 59:54That's like, oh, that's cute.
- 59:56But, like, no.
- 59:58There's, like, five reasons why that experiment won't work.
- 1:00:02But this one was very good at it.
- 1:00:04It was also really good at guide RNA design.
- 1:00:07You know, the guide RNA that we were talking about.
- 1:00:09Yes.
- 1:00:09Yes.
- 1:00:10It's not as simple as just, oh, this is the sequence that I want, right?
- 1:00:13You want to design a sequence that will only go to your specific location in the genome and not get misidentified with other parts of the genome, right?
- 1:00:22Because at the end of the day, it's a lock and key.
- 1:00:24Right.
- 1:00:24But if the lock and key closely matches elsewhere, then you're going to start cutting other parts of the genome.
- 1:00:29Right.
- 1:00:29And then your whole experiment fails.
- 1:00:31So it's really good at guide RNA design.
- 1:00:34And it's also really good at scientific question and answer.
- 1:00:36Like if you want to learn more about how this stuff works or what is the logic behind a certain experimental step, you can ask it and it actually gives it back to you.
- 1:00:45So the Stanford lab that developed this is actually already using it with its PhD students.
- 1:00:50And now it's out like in the open.
- 1:00:52And I think it's going to be really cool for expanding the broader impact of CRISPR, Cas9, and these CRISPR technologies.
- 1:01:02There's something like 7,000 to 10,000 single gene disorders out there.
- 1:01:08And in order to work on them, if you can make it easier for the researcher, that's a huge win.
- 1:01:16There's going to be, and again, obviously, we will be remiss and get escoriated in the comments if we don't talk about the obvious third rail related to all of this stuff, which is you're combining these two extremely powerful but also extremely dangerous frontier technologies.
- 1:01:36And they have this accelerant effect when they're now combined and also open sourced.
- 1:01:42And so the obvious kind of the safety, you know, this is why people talk so much about AI safety.
- 1:01:50It's not always the most obvious, like, oh, it's just going to be in a robot and then we're going to have drones with computer vision killing everybody.
- 1:01:59It is more so if you have, you know...
- 1:02:03in some place, a group of expert scientists who are in this arena, but maybe are under a repressive regime that wants to do crazy stuff.
- 1:02:13And now they have accessibility to better tools of discovery.
- 1:02:18Yeah.
- 1:02:19There's a whole like human piece to it.
- 1:02:22There is this technology piece in its entirety.
- 1:02:25Like how do you decide how to Stanford decide to release it or not release it?
- 1:02:29That's right.
- 1:02:30I mean, they did.
- 1:02:31So to be fair, they did have like guardrails in place.
- 1:02:35One of the guardrails was like, you know, if you're trying to like do CRISPR on like COVID or HIV, it'll just be like, no.
- 1:02:42What are you doing?
- 1:02:43Why are you doing that?
- 1:02:45If you give it an identifiable DNA sequence, so like something that's more than like 30 base pairs long, which is something that you can maybe identify with individuals.
- 1:02:54If you want patient confidentiality, again, it'll lock down.
- 1:02:58I mean...
- 1:03:00Obviously, there's ways to get around this, right?
- 1:03:03And it is concerning.
- 1:03:05I just want to make sure we at least touch on that.
- 1:03:07And I agree with you.
- 1:03:08Like, I think it's a very important point.
- 1:03:11It's not the focus of this discussion.
- 1:03:13Yeah.
- 1:03:13But, you know, as we talk about all these things, everything has sort of this double-edged sword.
- 1:03:20And it goes back to the whole kind of quote where every technology is agnostic.
- 1:03:24It's about how ultimately we as humans choose to implement it.
- 1:03:28So it's a human...
- 1:03:30CRISPR doesn't kill people.
- 1:03:31People kill people.
- 1:03:35Sure, bro.
- 1:03:35But it is a worthwhile discussion point.
- 1:03:38And if there's interest in this topic of CRISPR and us kind of continuing on the sort of safety conversation, just let us know in the comments.
- 1:03:45And we'll definitely come back to touch on this.
- 1:03:47This is, I think, the fourth or fifth time.
- 1:03:49And we talk about safety every single time.
- 1:03:50Yeah, every time.
- 1:03:51Maybe not as in depth.
- 1:03:52But these are things that, again, folks at the Frontier do have to start thinking about.
- 1:03:59Because, you know, we already seen what happened with nukes.
- 1:04:03And so it's the same story.
- 1:04:05Yeah.
- 1:04:06History doesn't repeat, but it rhymes.
- 1:04:07Yes, exactly.
- 1:04:08But this is really, really fascinating.
- 1:04:10Yeah.
- 1:04:10And I'm, you know, 2020.
- 1:04:13So five years ago, the Nobel Prize went to them.
- 1:04:16One of my favorite Nobel Prizes over the past 10 years, definitely, is Christopher.
- 1:04:20I actually remember, you know, in 2012 at Princeton as an undergrad,
- 1:04:26I was just having a conversation at a dinner table with a friend of mine who was in molecular biology and she was talking about this paper that had just come out in science about programmable DNA.
- 1:04:41And that's where I... At the dinner table is when I first heard the word CRISPR.
- 1:04:45I was like, like CRISPR, like crispier, like food.
- 1:04:50And then she was like, no.
- 1:04:51And then she described it to me and I was like, oh.
- 1:04:55Oh, shit.
- 1:04:56Yeah.
- 1:04:56Yeah.
- 1:04:57This is insane.
- 1:04:59We're going to start referring to people like KFC Chicken.
- 1:05:01Are you original or crisper?
- 1:05:02Yeah.
- 1:05:03Because people, it's going to start being a thing with everyone.
- 1:05:05And I still remember that day when it was like, it was sophomore year, 2012.
- 1:05:08Yes.
- 1:05:08And I was like, whoa.
- 1:05:10Yeah.
- 1:05:10No, big deal.
- 1:05:11Whoa.
- 1:05:11This is a big deal.
- 1:05:12Big deal.
- 1:05:13Yeah.
- 1:05:13Very, very big deal.
- 1:05:14This is our first Nobel Prize reference story of the day.
- 1:05:18Again, Nobel Prize week.
- 1:05:20It's next week.
- 1:05:21Be sure to tune in.
- 1:05:22We're going to be doing crazy coverage.
- 1:05:24The best coverage from First Principles.
- 1:05:27Nowhere is going to be better.
- 1:05:28The best is going to be the greatest.
- 1:05:31It is the best coverage.
- 1:05:32They say it's the best.
- 1:05:35Okay, so we just finished talking about CRISPR, which was our first favorite Nobel Prize.
- 1:05:41We're going to talk about our second one, a great achievement for American science.
- 1:05:46This was all America.
- 1:05:47This is us.
- 1:05:48Yeah.
- 1:05:49America.
- 1:05:50And which is the sort of LIGO.
- 1:05:51And again, we're tying it from the AI story.
- 1:05:54that just came out this year, to the history of this project and how AI is making this initial tool and kind of area of research even better.
- 1:06:04So the headline on this LIGO story, new algorithm hushes unwanted noise in LIGO may lead to more black hole discoveries.
- 1:06:13So this is from researchers at Caltech.
- 1:06:15And their idea was we want to make it easier for LIGO to find black holes with eccentric or oblong orbits, as well as catch mergers earlier in the coalescing process.
- 1:06:25Yes.
- 1:06:25They published their paper in Science, which is this AI kind of context.
- 1:06:30But we've talked about LIGO on the podcast before.
- 1:06:33And I remember you talking about how this is sort of this, like, long tail of this initial contribution of what Einstein predicted.
- 1:06:44100 years 100 years ago yeah and so we're gonna do the same thing again which is kind of look at this story of the scientific curiosity journey from that initial prediction now to how all these new ai things are actually making ligo better better yeah it's kind of crazy 100 years ago
- 1:07:08Actually, more than 100 years ago.
- 1:07:10So, 1915.
- 1:07:10Okay.
- 1:07:12Einstein publishes his General Relativity.
- 1:07:15Yes.
- 1:07:15Which is a new way of thinking about gravitation, not as a force in the sense of Newton, where there's a force between two bodies, but actually as a disturbance in the actual fabric of space and time, where...
- 1:07:31Now you have this unified quantity called space and time, which he had sort of already unified in 1905 with special relativity.
- 1:07:39But special relativity dealt with inertial reference frames, which means a reference frame here, let's say us sitting stationary, and then a frame of someone in a car that's moving in a straight line.
- 1:07:53with constant velocity.
- 1:07:55The idea is any experiment that he does in there is the same as any experiment that we do stationary.
- 1:08:01This is kind of, he's taking Galilean relativity from Galileo's time and taking it very, very seriously.
- 1:08:08Right?
- 1:08:08And he's combining that with the fact that the speed of light is constant to get special relativity.
- 1:08:13All these consequences about how time is really relative, space is really relative, and there's this metric that is a combination of the two that is the thing that is invariant.
- 1:08:24So now we get special relativity.
- 1:08:25General relativity is where he generalizes it to say, what about accelerating reference frames?
- 1:08:30What if that train was not moving in a constant velocity, but was moving around?
- 1:08:37Was turning, was speeding up or slowing down?
- 1:08:42How would that affect...
- 1:08:44these calculations that I've been making.
- 1:08:45And he comes up with general relativity, which is this idea that gravity and acceleration, gravity and this change in space and time are actually the same thing.
- 1:08:54We don't have to get into the whole details, but at the end of the day, it created this sort of nice...
- 1:09:03mathematical framework for how we identify and understand space and time in a very nitty-gritty, precise way.
- 1:09:11Which impacts us, you know, every day.
- 1:09:13Every day.
- 1:09:14And I mean, you know, GPS, for example, is impacted by general relativity.
- 1:09:18The fact that GPS satellites are so far up means that they have a smaller gravitational field due to the Earth compared to us down here, which means that their clocks...
- 1:09:31actually run a little bit faster than ours do.
- 1:09:35Right.
- 1:09:35You would think because of special relativity that their clocks would run slower.
- 1:09:39Yes.
- 1:09:40Right?
- 1:09:40Because they're moving so fast.
- 1:09:42Yes.
- 1:09:42But actually the general relativistic effect is something like four times...
- 1:09:47The effect from special relativity.
- 1:09:49So special relativity, the fact that they're moving so fast means that the clock is slowing down.
- 1:09:54But the fact that they're in such a smaller gravitational environment, right, where the gravity is so less, means that they're actually moving faster.
- 1:10:02Which is why there's a correlation.
- 1:10:03These things matter.
- 1:10:04Yeah, and actually measuring that and accounting for that is essential to how GPS works.
- 1:10:11How we get precision.
- 1:10:12Yeah, because at the end, GPS can...
- 1:10:15localized me to within a few meters of where I actually am, right?
- 1:10:20That few meters, if you think about it, the way they actually do it is from the light traveling between us and the satellite and the time delay between us and several different satellites, right?
- 1:10:31And then triangulating from those several different satellites to where we are.
- 1:10:35Well, in order to actually measure that time difference, you need to have extremely precise clocks on that clock.
- 1:10:42GPS satellite.
- 1:10:43Yes.
- 1:10:44That precise clock is going to be so precise that it is going to feel these relativistic effects.
- 1:10:50And so you need to have an active mechanism that accounts for the fact that that clock is going faster than this clock by exactly the amount that Einstein's field equations say that they will go faster by.
- 1:11:01And then you do the math and then you like, oh, you're here, you know, and you need to go over there and so on and so forth.
- 1:11:06That's actually
- 1:11:06a really good example.
- 1:11:07So it's very much involved in...
- 1:11:10Right, right.
- 1:11:10It's a good example of how GR relates to a very everyday use case that everyone can understand.
- 1:11:17Everyone, yeah.
- 1:11:19Everyone's used GPS.
- 1:11:20Yes.
- 1:11:20Okay, so now we're getting to the fact that Einstein publishes these field equations.
- 1:11:26People start trying to find solutions to the field equations, okay?
- 1:11:30Which means to say...
- 1:11:32The field equations give us a way to understand what matter does to space and what space does to matter.
- 1:11:39The great saying by John Wheeler, who we'll get to later on, is that...
- 1:11:46Space tells matter how to move and matter tells space how to curve.
- 1:11:52Okay.
- 1:11:52That's effectively what Einstein's field equations are.
- 1:11:56They're a way for us to mathematically describe the stretching and turning of space time.
- 1:12:02Okay.
- 1:12:03So space time becomes this sort of.
- 1:12:07like field in some sense.
- 1:12:09Okay?
- 1:12:10It's like everywhere and it's got a way to stretch and stuff.
- 1:12:13And one can imagine people start asking, can I make waves?
- 1:12:16Okay?
- 1:12:18In this field.
- 1:12:20In this sort of field of space-time.
- 1:12:22You can imagine, right, like if I've got ropes or if I've got a rubber band, right, I can create waves in my rubber band.
- 1:12:29If I have a bunch of rubber bands lined up together and I stretch one and then that sort of propagates on the rest, you can create these waves in rubber bands.
- 1:12:37And if space-time is this sort of elastic thing, then I should be able to create waves in space-time.
- 1:12:43The thought, my initial thought on that is...
- 1:12:48You must need an immense amount of energy.
- 1:12:53Energy, yes.
- 1:12:54An insane amount of energy.
- 1:12:55In order to disrupt the fabric of space-time.
- 1:12:59Yeah, yeah.
- 1:13:00I mean, and you're exactly right.
- 1:13:01You do need an insane amount of energy to disrupt the fabric of space and time.
- 1:13:05But before we even try to think about what could cause waves in space and time, you've got to first show that the Einstein field equations...
- 1:13:18Admit a solution that looks like the wave equation.
- 1:13:22Okay.
- 1:13:23Okay?
- 1:13:23The wave equation is something that's been around for hundreds of years.
- 1:13:26And it's very well defined, you know, sines and cosines, traveling.
- 1:13:31The wave equation is a very simple second order differential equation that's basically saying that the amount of curvature that I have in space tells me how much acceleration I have in time.
- 1:13:42And that's...
- 1:13:43Basically how the wave equation works, right?
- 1:13:45There's a second derivative in space.
- 1:13:47There's a second derivative in time.
- 1:13:49And they're related by the velocity of propagation.
- 1:13:52So Einstein sets out to see if this works in his...
- 1:13:58in his equations of special relativity, in his field equations.
- 1:14:02So at this point, it's in the 1930s.
- 1:14:04Einstein's already at Princeton, New Jersey.
- 1:14:08He's already at the Institute for Advanced Study.
- 1:14:12At this point, I don't think the institute had actually been made, and so he had an office in Frist Campus Center, which used to be the old physics building and the math building on campus.
- 1:14:23Spent a lot of 2 a.m. nights.
- 1:14:24Yeah, yeah, yeah, yeah, with the late meal.
- 1:14:26Yeah, late meal was classic.
- 1:14:28So he's sitting there and he tries to find a solution to the wave equation in his field equations.
- 1:14:40He does the math, and he actually comes up with the fact that what he notices are these things called singularities, which he can't quite get rid of when he's trying to do this analysis.
- 1:14:54And so he writes a paper saying that the field equations do not admit wave solutions.
- 1:15:02He writes this up, and he sends it over to the physical review.
- 1:15:06The physical review at this point was...
- 1:15:11The editor was John Tate, and he is kind of a stickler for the peer review process.
- 1:15:19At this point, Einstein had already sent in a bunch of papers to the peer review.
- 1:15:22There was the very famous EPR paper, Einstein, Podolsky, Rosen, which is the one that was talking about local variables solving quantum mechanics.
- 1:15:31He was saying that, you know, this whole quantum stuff is weird.
- 1:15:34Maybe there's some like...
- 1:15:36hidden variable that explains quantum mechanics.
- 1:15:39That was the famous EPR paper.
- 1:15:41There was also the Einstein Rosen bridge paper that he had published in the physical review.
- 1:15:48So he's had a pretty good relationship with the physical review.
- 1:15:51So he sends this one in.
- 1:15:53And he says that, you know, my equations do not allow for wave-like solutions.
- 1:15:59John Tate sends it over to his buddy H.P.
- 1:16:03Robertson, who's also in the Princeton physics department.
- 1:16:09So, you know, Einstein sends it to John Tate.
- 1:16:11John Tate sends it back to Princeton.
- 1:16:13And Robertson finds an error in the paper, okay?
- 1:16:17He finds that the singularities that Einstein is so worried about and...
- 1:16:23the reason why he thinks that wave equations won't exist, are actually just coordinate singularities.
- 1:16:28They're not actually real physical singularities.
- 1:16:31Coordinate singularities are something like, you know, trying to find the longitude of the North Pole, something like that.
- 1:16:36It's an artifact of, like, our...
- 1:16:39version of how we're keeping track of latitude and longitude, right?
- 1:16:43But the North Pole could be anywhere, right?
- 1:16:45It's just we like the North Pole at the top because that's how it's spinning.
- 1:16:49But you can easily imagine a coordinate system where the North Pole and the South Pole are on the opposite sides of the equator, and we just have really convoluted equations of mechanics for how physics on the Earth works, right?
- 1:17:01But at the end of the day, it's a choice that we've made as humans.
- 1:17:05on where to put the zero of our coordinate system, right?
- 1:17:08It's an artifact of the coordinate system.
- 1:17:10So Robertson actually looks at Einstein's paper, and he's like, actually, these singularities are coordinate singularities.
- 1:17:16They're not physical singularities.
- 1:17:19So he writes back to Tate.
- 1:17:20Tate then...
- 1:17:21pushes back on Einstein and he's like, hey, I got these peer reviews.
- 1:17:26I was wondering if...
- 1:17:27Very nicely.
- 1:17:28The letters are still there.
- 1:17:29Not like reviewer number one.
- 1:17:31No, not like reviewer number one from the Mars paper.
- 1:17:33Yes.
- 1:17:33Where it's like, you need to...
- 1:17:35This needs to get rejected.
- 1:17:36It's like, this is Einstein we're talking about.
- 1:17:38So obviously you have to be like, you know, they have these comments.
- 1:17:42Can you take a look?
- 1:17:45And Einstein is just livid.
- 1:17:47Yeah.
- 1:17:49He's like, I can't believe you showed my paper to someone without my consent.
- 1:17:56Given this, I'm just going to publish somewhere else.
- 1:17:59He retracts his paper.
- 1:18:01The goat.
- 1:18:02He never publishes in physical review again.
- 1:18:05And John Tate goes down as the guy who editorialized Einstein.
- 1:18:11But he was a man true to his word.
- 1:18:14He was like, I don't care if you're Einstein or God, you're going to go through the same peer review.
- 1:18:18And hey, if Robertson, who's a great mathematical physicist in his own right, says something is wrong, maybe you need to pay attention, right?
- 1:18:26Seems reasonable.
- 1:18:27Seems reasonable.
- 1:18:29Einstein retracts his paper.
- 1:18:31He gets word from his assistant elsewhere about Robertson, because Robertson goes to his assistant.
- 1:18:37It's like, you know, you guys are having trouble with these singularities.
- 1:18:40Like, you know, there's one way that you can just like do this and then blah, blah, blah.
- 1:18:44And then the math trick works out.
- 1:18:46And so Einstein gets word from his assistant that, you know, there's a way to counteract it.
- 1:18:53He goes back to the drawing board.
- 1:18:54And Einstein, true to his physics side, right, he sets aside his ego and he's like, okay, that was bad.
- 1:19:01And he corrects his paper and he publishes it in a Philadelphia journal.
- 1:19:06I think of the Benjamin Franklin Society or something, some random journal.
- 1:19:10You know, not the physical review.
- 1:19:12Right, right.
- 1:19:13Right.
- 1:19:13And it's a totally new paper.
- 1:19:15Okay.
- 1:19:16And it's a new paper that admits that gravitational waves can, in fact...
- 1:19:21be allowed in the space-time of Einstein's field equations.
- 1:19:25It's so funny, right?
- 1:19:26Because it's like this guy, like he, you should have just read the peer review.
- 1:19:33right he could have just read the peer review and like but but he had to go through all this he chose violence he chose violence and like at the end of the day he even admitted to himself that he was wrong and like corrected his paper but he never went back to the peer review that's a level of petty i aspire to be yeah yeah it's like i know i'm wrong but how dare you that's einstein dude you don't yeah anyways he never published in the peer review the the physical review ever again but that paper sort of established this idea that okay
- 1:20:04We can have gravitational waves.
- 1:20:05You can have waves in this system of space-time where space-time is this fabric.
- 1:20:11Yeah, that governs the dynamics of all things.
- 1:20:14Okay.
- 1:20:15So, all right, fine.
- 1:20:16Now we've got a paper that says gravitational waves do exist.
- 1:20:20Right.
- 1:20:21Okay?
- 1:20:21Just like electromagnetic waves.
- 1:20:23Yes.
- 1:20:24Okay.
- 1:20:24And just like electromagnetic waves, in order to create gravitational waves, you need accelerating bodies.
- 1:20:30So you can't have a thing that's just moving at constant velocity.
- 1:20:34Because it's not going to disturb the space.
- 1:20:35Because it's not going to disturb space in the way that it propagates out.
- 1:20:39Yes.
- 1:20:39Okay.
- 1:20:39It's going to create a disturbance, but that disturbance is just going to like sort of be local to it.
- 1:20:45Yes.
- 1:20:45Okay.
- 1:20:46And you're not going to get this like radiating effect.
- 1:20:48It's like if you're in a boat and you're stationary, you don't create a wake.
- 1:20:51Yes.
- 1:20:53But if you're moving...
- 1:20:54But in a boat, even a moving boat creates...
- 1:20:57This is a big...
- 1:20:58Okay.
- 1:20:59This is a fine detail.
- 1:21:01A boat that's moving at constant velocity is still going to create waves.
- 1:21:05Yes, that's fair.
- 1:21:05That's fair.
- 1:21:07A charged particle that moves at a constant velocity will not create a light wave.
- 1:21:12Light is only created from accelerating particles.
- 1:21:15So something that's moving in a circle means that it's changing velocity.
- 1:21:19That is going to create a radiating effect.
- 1:21:22Something that's speeding up or slowing down is going to create a radiating effect.
- 1:21:26But something that is moving at a constant velocity is not.
- 1:21:30There's actually a very simple argument for why this is the case.
- 1:21:34It's one of my fundamental...
- 1:21:35It's one of my favorite arguments from Einstein's special relativity.
- 1:21:40Okay?
- 1:21:40So, suppose...
- 1:21:44Not, right?
- 1:21:45We're going to do this by a proof of contradiction.
- 1:21:47Suppose not.
- 1:21:47Suppose that a charged particle that moves at a constant speed does create light.
- 1:21:54What if I were to boost myself into a reference frame that I'm moving with the charged particle at a constant speed?
- 1:22:01In my reference frame, that charged particle is stationary.
- 1:22:03Yes.
- 1:22:04So I'm not going to see any light.
- 1:22:07But now there's a contradiction.
- 1:22:08Yeah, right.
- 1:22:08Immediately, got it.
- 1:22:09Immediately, there's a contradiction.
- 1:22:11Because a stationary observer observed light, but me moving with this particle does not observe light.
- 1:22:18It would be something if the stationary observer observed a particle with some light, and I observed it at a different energy, right?
- 1:22:26Yes.
- 1:22:26Maybe it was like boosted in ultraviolet or down in infrared or something like that.
- 1:22:30But the fact that I observed no light...
- 1:22:31Yes.
- 1:22:32...is unphysical.
- 1:22:33Yes.
- 1:22:33Because both me and the stationary observer should observe the same physics.
- 1:22:38Yes.
- 1:22:39Right?
- 1:22:39Yes.
- 1:22:40So...
- 1:22:41It's a consequence of relativity.
- 1:22:42The constant velocity motion does not radiate.
- 1:22:46The same thing happens with gravity, right?
- 1:22:48Suppose there's a gravitational object that's moving at a constant velocity.
- 1:22:52If I boost myself into that reference frame, that object is now stationary, and I shouldn't observe any gravitational waves.
- 1:22:59Well, if I don't observe any gravitational waves in my...
- 1:23:03in my frame of reference with the body, then a stationary observer should also not observe gravitational waves.
- 1:23:09On the other hand, if it's accelerating, if it's moving, if it's accelerating and it's speeding up or it's slowing down, then no matter what inertial frame I choose, it's also going to be either speeding up or slowing down.
- 1:23:20So I am going to observe some form of gravitational radiation, or in the case of charged particles, some form of electrical radiation, light.
- 1:23:28Yes.
- 1:23:29You know, that's kind of interesting.
- 1:23:30No, that's a great...
- 1:23:31It's such a great, like, simple argument you can make using just the symmetries of physics.
- 1:23:35Yes.
- 1:23:36So anyways, we need something that's accelerating, okay?
- 1:23:42So for the longest time, gravitational radiation was just this thing that, you know, it's hypothesized.
- 1:23:47But even Einstein said, you're never going to find it.
- 1:23:49Yeah.
- 1:23:50Never.
- 1:23:51Because you can do a back of the envelope calculation about how much stuff would stretch and squeeze by.
- 1:23:59Right.
- 1:24:00And it's on the factor of like 10 to the minus 20.
- 1:24:03Meaning like the actual fabric that would be measurable by us would be so... Any length would be corrected by 10 to the minus 20.
- 1:24:12Right?
- 1:24:12Like, if you take a meter stick, an atom is 10 to the minus 10 of that meter stick.
- 1:24:18Right?
- 1:24:18So it's an atom of an atom.
- 1:24:19It's just like...
- 1:24:21Even Einstein's like, yeah, okay.
- 1:24:22Right.
- 1:24:23Like, this is a cool, like, you know, theoretical exercise, but...
- 1:24:26So the point being that his view was like, we won't be able to get to a level of experimental verification because of the...
- 1:24:35The scope is just so outside.
- 1:24:37Like it was an engineering problem for detection.
- 1:24:40But the engineering problem required physics that was like stupid.
- 1:24:45Yeah, yeah, yeah.
- 1:24:46Right?
- 1:24:46Yeah, yeah.
- 1:24:47You know what I mean?
- 1:24:48It's like a cool thing.
- 1:24:49Yeah.
- 1:24:50But it's a cool thing.
- 1:24:50Yes.
- 1:24:51Okay.
- 1:24:531970s actually is when we first got a confirmation that gravitational waves exist.
- 1:24:58Okay.
- 1:24:58It was by Taylor and Holtz.
- 1:25:01Actually, one of their plaques is on the Princeton University physics thing because he won the Nobel Prize for it.
- 1:25:10I think he was a postdoc at the time at Princeton or maybe a PhD student.
- 1:25:16So they used the Arecibo.
- 1:25:20radio telescope.
- 1:25:21Have you seen this thing in Puerto Rico?
- 1:25:23It's a giant radio telescope that's like in a bowl created by the geography of the mountain.
- 1:25:30Wasn't it recently kind of had like a hurricane came through or something, had a little damage to it?
- 1:25:34Yes, it did.
- 1:25:35And then they had to...
- 1:25:36And they had to fix it and everything.
- 1:25:38But it's a bowl created by the earth that we then put concrete over.
- 1:25:43And then it basically just scans the sky with the earth and tries to find radio sources.
- 1:25:49So they were trying to look for pulsars at the time with that radio source.
- 1:25:53And what they found was a pulsar.
- 1:25:57And they were very happy because back in the day, pulsars were very new, so they found a new pulsar.
- 1:26:02But this was a very weird pulsar.
- 1:26:04It was a pulsar that had a cycle of 60 milliseconds.
- 1:26:09So 17 times a second it would go down.
- 1:26:15And a pulsar is basically a neutron star that kind of acts like a lighthouse.
- 1:26:19It's got these strong magnetic fields, so it's got these jets of radio light that are coming out.
- 1:26:24And it's a lighthouse in the sense that as it rotates...
- 1:26:28Right?
- 1:26:28Yes.
- 1:26:29The part of the beam, the radio beam, is going to just like go through the earth.
- 1:26:33Yes.
- 1:26:34Every 60 milliseconds.
- 1:26:36Yes.
- 1:26:36Right?
- 1:26:36Which is quite fast.
- 1:26:37It's quite fast.
- 1:26:38And it's a really precise clock.
- 1:26:41Okay?
- 1:26:41It's one of the...
- 1:26:42These pulsars are some of the most precise clocks...
- 1:26:45ever made in the universe right because it's really hard to slow down a neutron star that's the size of several suns that just because of the conservation of angular momentum it's just going to keep going okay so most pulsars they're very reliable they'll just be like clockwork this pulsar was different okay okay because this pulsar every once in a while it would the the pulses would arrive
- 1:27:13three seconds too late or three seconds too early.
- 1:27:16Remember, it's going at 60 milliseconds, but you can plot the trajectory of how their delay is.
- 1:27:23Yes.
- 1:27:24And that delay was happening three seconds too late or three seconds too early.
- 1:27:30And what they figured was this pulsar is actually rotating
- 1:27:36with another neutron star.
- 1:27:38That other second neutron star is also a pulsar, but we're not seeing it because the lighthouse isn't crossing our line of sight.
- 1:27:46So it's maybe doing one of these and we're missing that lighthouse effect.
- 1:27:49But this one is coming right at us and it's revolving in this binary pulsar system.
- 1:27:54Got it.
- 1:27:55This became a really nice test bed for general relativity.
- 1:28:00Because now all of a sudden you had
- 1:28:03rotating objects that were massive that were accelerating right yes because they're they're revolving around each other which means they're constantly correcting their motion because of the gravity between them which means if they're close to each other right three seconds in light distance like the moon is about one and a half seconds away so this is imagine like it's the earth and like
- 1:28:24Another two moons away.
- 1:28:26Yes.
- 1:28:26Two stars that are like the size of the sun and more.
- 1:28:30Yes.
- 1:28:31That are revolving around each other, right?
- 1:28:32So the point is they're quite close.
- 1:28:34They're quite close.
- 1:28:35So their gravitational impact, their gravity independently is going to have a high impact on each other because of proximity.
- 1:28:41Exactly.
- 1:28:42Yeah.
- 1:28:42Which means that according to Einstein's GR...
- 1:28:46these should be radiating gravitational waves.
- 1:28:50If they're radiating gravitational waves, then they should be losing energy because it takes energy to deform space and time.
- 1:28:57Yes.
- 1:28:57And if they're losing energy, they should be falling into each other and they should be rotating faster.
- 1:29:03So you can do all of the math.
- 1:29:04I was going to say you can do the math.
- 1:29:05You can do the math, and you can figure out, according to GR, how fast should that decay be, right, of their total energy.
- 1:29:13Yes.
- 1:29:14And it's a beautiful plot that they have in their paper, where it shows a line that shows the theoretical prediction, and then it shows dots of the experimental.
- 1:29:23And the dots are lining up exactly exactly.
- 1:29:26To Einstein's GR.
- 1:29:27Which means the math in the GR paper is now, which was theoretical at the time, there's now an experimental observation that was verifiable to what the underlying sort of statement of work is around GR.
- 1:29:41Yeah, exactly.
- 1:29:42And it's like, where could this energy be going?
- 1:29:44It has to be going in the gravitational waves, which is what's...
- 1:29:48predicted by this equation.
- 1:29:50And the equation also predicts exactly the decay, and that's exactly what we see.
- 1:29:54And now we've been watching this pulsar for the past 40 years now.
- 1:29:57Which makes sense.
- 1:29:58And it just continues down.
- 1:29:59It's like the perfect experiment in the sky.
- 1:30:01Yeah.
- 1:30:01For any number of different types of observational research, this being just won.
- 1:30:06Yeah.
- 1:30:07And they won the Nobel Prize in 1993 in physics for this discovery.
- 1:30:10It was a very big one, right?
- 1:30:11It established the reality, the experimental reality of gravitational waves.
- 1:30:16Okay.
- 1:30:17Now, I just want to make a note that what's interesting is it required no specialized measurement equipment at the time.
- 1:30:25It was just...
- 1:30:27What we already had, radio telescopes?
- 1:30:29Yeah, it was just a radio telescope.
- 1:30:30Radio telescope and math.
- 1:30:30Arecibo, yeah.
- 1:30:31Arecibo and math, right?
- 1:30:33And so this established at least the existence of gravitational waves, of the fact that space and time undulate in this wave-like manner, and it carries energy, the same exact amount of energy that Einstein's equations predict.
- 1:30:48Okay?
- 1:30:48Now, it's something to go from these things exist to...
- 1:30:53to let's actively try and sense them.
- 1:30:56Right.
- 1:30:57Right.
- 1:30:57Right.
- 1:30:57Because that's what Einstein was going at.
- 1:30:59He was like, this is going to be impossible to sense these.
- 1:31:01This was an indirect confirmation.
- 1:31:04Yeah.
- 1:31:04It's an indirect observation.
- 1:31:05But it was not a direct observation.
- 1:31:07It's not like, oh, that was, I just saw one.
- 1:31:10Yeah.
- 1:31:10Right.
- 1:31:11It's just like, oh, this thing is just,
- 1:31:13putting it out into the sky, and we're seeing it because it's losing energy.
- 1:31:18Right.
- 1:31:19So that's the indirect observation.
- 1:31:20By the conservation of energy, that energy has to go somewhere.
- 1:31:23Where does it go?
- 1:31:24Into these gravitational waves.
- 1:31:25Yep.
- 1:31:25Okay.
- 1:31:26So now we're getting to...
- 1:31:29So this is the 1970s.
- 1:31:30They find this thing.
- 1:31:33Also in the 1970s,
- 1:31:35people start thinking about how do we actually make direct detection of gravitational waves.
- 1:31:41So that's where we start getting into people like Feynman, actually.
- 1:31:44Feynman starts...
- 1:31:46He gave this talk about sort of a thought experiment of how to actually detect gravitational waves.
- 1:31:52And he showed that, you know, if you had like...
- 1:31:55a sort of rod attached to springs and stuff.
- 1:31:58And if a gravitational wave of insanely high capacity went through, then the rod would actually undulate, because the springs would be attached to that space and time.
- 1:32:10So this thing would move, and then part of the energy of the gravitational wave would actually go into the spring, and then if you measured the spring, you could actually measure the gravitational wave.
- 1:32:20So he showed that mathematics of something like this,
- 1:32:24A system that could do the direct observation and what the structure of that system would be and why it can work.
- 1:32:30Exactly.
- 1:32:30And so given that sort of theoretical work of showing that a system like that would work, this guy Joseph Weber from the University of Maryland in the 1960s and 70s, he created a gravitational wave detector, which was sort of something that he could fit inside a laboratory.
- 1:32:46And he said that he found some.
- 1:32:49Now we know that he probably didn't because people couldn't replicate it as his experiment.
- 1:32:53And science is all about replication, right?
- 1:32:55And probably he didn't find any.
- 1:32:58And it sort of marred the field because, you know, you've got this guy who's saying, I found him, but he didn't.
- 1:33:05And he was an honest scientist.
- 1:33:06But, you know, even honest scientists can get sort of hung up and not see the sources of their errors, right?
- 1:33:15So it was kind of lacking, let's say, the field.
- 1:33:19Okay, so this is where the two heroes of our story come in.
- 1:33:26Kip Thorne and Rainer Weiss.
- 1:33:28Okay?
- 1:33:30And to really understand where they come in in the 1970s and 80s, we got to go back to their roots.
- 1:33:36Okay?
- 1:33:38Kip Thorne gets his PhD at Princeton under John Wheeler.
- 1:33:44Okay?
- 1:33:44John Wheeler is a...
- 1:33:50seminal figure in the field of physics.
- 1:33:54He's kind of like, I would say, the American Arnold Sommerfeld.
- 1:33:57Remember Sommerfeld that we talked about?
- 1:33:59Sommerfeld being this guy who tutored amazing physicists in their own right, but never won the Nobel Prize himself.
- 1:34:07John Wheeler is one of those guys.
- 1:34:09He tutored Kip Thorne, won the Nobel Prize.
- 1:34:11He tutored Richard Feynman, also got his PhD under John Wheeler.
- 1:34:15He tutored Hugh Everett,
- 1:34:18who is the guy behind the many worlds interpretation of quantum mechanics, this idea of multiverses and all the, you know, Marvel stuff.
- 1:34:25He also tutored Jacob Bekenstein, which is a guy who did seminal contributions to black hole thermodynamics, the idea of, like, entropy in black holes and information in black holes.
- 1:34:38He sort of revamped...
- 1:34:41He made general relativity cool again after the war.
- 1:34:45Yeah, okay.
- 1:34:46Yeah, because...
- 1:34:48General relativity was sort of this field that was not cool, okay?
- 1:34:52It wasn't something that you could do direct detection on.
- 1:34:55Einstein had sort of closed the book by finding the Einstein field equations.
- 1:35:00And then people thought it was sort of just, oh, like, you know...
- 1:35:04It's just book work at that point of like trying to find new directions with GR.
- 1:35:08Is it similar to how when people say string theory is cool on paper, but we can't do anything experimentally to really see the things that are being argued?
- 1:35:17Yeah.
- 1:35:17Like a parallel.
- 1:35:19It's kind of parallel.
- 1:35:20GR, I wouldn't compare to string theory, obviously, because GR actually has insane experimental, even back then.
- 1:35:28Okay, fair.
- 1:35:28Right, even like Mercury's orbit was explained by GR.
- 1:35:31Fair.
- 1:35:32One had done the detection of bending of light around a solar eclipse.
- 1:35:36That was Arthur Eddington.
- 1:35:38So GR had its confirmation.
- 1:35:40So you're saying string theory is trash.
- 1:35:41I'm kidding.
- 1:35:41I'm kidding.
- 1:35:41Well, okay.
- 1:35:42Actually, speaking of string theory, string theory actually started with John Wheeler.
- 1:35:49John Wheeler...
- 1:35:52came up with this idea of the S matrix, which was, I don't understand much about it, but it's some way of like defining a new way of dealing with quantum mechanics that, that had to do with combining gravity and quantum mechanics.
- 1:36:07S matrix was then taken by Werner Heisenberg and developed into a theory.
- 1:36:10And then that sort of.
- 1:36:12form in the string theory later on.
- 1:36:14So John Wheeler is even, in fact, responsible for the genesis, the very, very embryonic genesis of string theory.
- 1:36:24He did a lot of really crazy stuff, dude.
- 1:36:27He did S-matrix theory.
- 1:36:28He coined the term wormhole.
- 1:36:31He did the one electron universe.
- 1:36:33I don't know if you've heard about that, where it's like every electron is just one electron in many different... Like, people love trying to go into, like...
- 1:36:41the science fiction of this kind of stuff.
- 1:36:44He popularized the term black hole.
- 1:36:47He also actually was one of the first people to foray into quantum gravity, of trying to combine quantum mechanics with gravity.
- 1:36:54So this incredible, incredible physicist sort of became the, you know...
- 1:37:02this godhead status at Princeton physics, attracted the talent, created talent with Kip Thorne and with Feynman, but he never himself won the Nobel Prize.
- 1:37:12He was the prince who never became king.
- 1:37:14Yeah, but I mean, to those who know physics, like John Wheeler is a very big deal, right?
- 1:37:22Yeah, he was one of the few people who...
- 1:37:24He defended Freeman Dyson when Freeman Dyson was going up against Oppenheimer.
- 1:37:30And yeah, it was like...
- 1:37:32He's one of the few guys that can go against the bigwigs, even go up against Einstein and be like, Nah, that doesn't make sense.
- 1:37:37And Einstein would actually listen instead of being like, I'm never going to publish here ever again.
- 1:37:42You know?
- 1:37:42Yeah.
- 1:37:44And Kip Thorne was Wheeler's PhD student.
- 1:37:49And Wheeler sort of started this idea of revamping general relativity.
- 1:37:55Okay.
- 1:37:56Kip Thorne grew into that.
- 1:37:58They wrote textbooks together.
- 1:38:00And Wheeler was the sort of theoretical part of the wing.
- 1:38:03Mm-hmm.
- 1:38:04And then there was this experimental part that was Robert Dickey.
- 1:38:08Robert Dickey is another one of these guys, great prince and greats.
- 1:38:12He's responsible for the invention of the lock-in amplifier, which is an electrical way of finding small electrical signals that are of some characteristic frequency in a bastion of noise.
- 1:38:27He also...
- 1:38:29was the discoverer of the cosmic microwave background.
- 1:38:32Okay, the CMB, the radiation from the Big Bang.
- 1:38:36He was one of these first sort of...
- 1:38:39Applying general relativity to cosmology problems.
- 1:38:42And him and his student Wilkinson and Peebles published the paper right after the experimental discovery.
- 1:38:50They were actually planning to make a dish to observe the cosmic microwave background.
- 1:38:56And then meanwhile, unbeknownst to them...
- 1:38:59Penzias and Wilson were neighboring in Bell Labs, which is right down the street from Princeton.
- 1:39:05They were stuck with a microwave antenna.
- 1:39:08They're trying to do research with microwave antenna, and they keep getting this noise.
- 1:39:11Yep.
- 1:39:12Yep.
- 1:39:12And they're like, what the hell is this noise?
- 1:39:14And they're trying to find where the noise is coming from.
- 1:39:16One of them actually crawled in and started scraping the pigeon poop.
- 1:39:21That was in the antenna.
- 1:39:22Because they're like, I don't know, maybe it's the pigeon poop.
- 1:39:24And they're like scraping.
- 1:39:25They got rid of the pigeon poop.
- 1:39:26The pigeon, the noise was still there.
- 1:39:29And they're like, dude, what is this noise that we're getting?
- 1:39:32And they called up Robert Dickey.
- 1:39:37And they're like, we're getting this noise.
- 1:39:39You guys are physicists at Princeton.
- 1:39:42And Dickie's like, he hangs up the phone and he tells his collaborators, boys, I think we got scoop.
- 1:39:48Because they're trying to make a thing.
- 1:39:51And these guys have done it.
- 1:39:52Penzias and Wilson immediately recognize what it is.
- 1:39:55They immediately publish.
- 1:39:57Dickie, Peebles, and Wilkinson published their paper on the CMB, the theoretical background, right after theirs.
- 1:40:04So you can see when they published, actually, it's like back to back in the same issue of the journal they're publishing, right?
- 1:40:12And Penzies and Wilson go on to win the Nobel Prize for the discovery.
- 1:40:16It really should have been a three-person with Dickey.
- 1:40:19But actually, years later, I think in the last two or three years, Jim Peebles, who was the guy who published the theoretical paper, he actually won the Nobel Prize.
- 1:40:30And it was kind of a validation.
- 1:40:31It was kind of a posthumous...
- 1:40:35Nobel Prize for Robert Dickey, who had already died.
- 1:40:39Yeah, yeah, yeah.
- 1:40:40But it was kind of cool that, like, you know, that collaboration finally won the Nobel.
- 1:40:46It got recognition.
- 1:40:47Yeah, it got recognition.
- 1:40:48Peoples won it for all of the other stuff that he did with cosmology later on.
- 1:40:51He actually showed that, you know, the CMB should look like this with this bumpy, wavy nature when you look at the power spectrum.
- 1:40:58And then when people did the power spectrum, they found the bumpy, wavy nature.
- 1:41:02Wilkinson, who was the other guy who did the...
- 1:41:05paper with them.
- 1:41:07The WMAP satellite, which is the Wilkinson anisotropy probe that was sent into space to actually capture the cosmic microwave background in excruciating detail, that was named after Wilkinson.
- 1:41:19So, you know, they got their credit in their own right, but it's unfortunate that Dickey didn't get his...
- 1:41:25recognition with the Nobel Prize.
- 1:41:26But one of Dickey's postdocs was Rainer Weiss.
- 1:41:29And Rainer Weiss still, to this day, says that, you know, one of his biggest influences in terms of physical thinking was Robert Dickey at Princeton.
- 1:41:38There's a beautiful photo of Kip Thorne and Robert Dickey standing right next to a plaque that commemorates...
- 1:41:45Sorry, there's a beautiful photo of Kip Thorne and Rainer Weiss, the two Nobel Prizes that were awarded for LIGO.
- 1:41:51They're standing next to the...
- 1:41:55plaque that commemorates Robert Dickey at Frisk Campus Center, right?
- 1:42:00There was a big celebration of his work, and both of them were in attendance, along with Wilkinson, who was in attendance.
- 1:42:09So, you know, it's this big tradition that sort of started at Princeton of, like, let's take GR seriously.
- 1:42:14Yeah, yeah.
- 1:42:15Okay?
- 1:42:17They move on to their different things.
- 1:42:18Kip Thorne goes to Caltech.
- 1:42:20Rainer Weiss goes to MIT.
- 1:42:21And they start thinking more earnestly about gravitational research in the experimental domain.
- 1:42:28Okay.
- 1:42:28And they're like, can we actually do this?
- 1:42:31Can we actually...
- 1:42:32The thing that Einstein said we couldn't do.
- 1:42:34Like, say that Einstein couldn't do.
- 1:42:36Can we actually do this?
- 1:42:37Okay.
- 1:42:39Reiner Weiss starts thinking about it.
- 1:42:41He's more on the experimentalist side.
- 1:42:43So he's from Dickey's group, right?
- 1:42:45So he's trying to actually think about the experiment.
- 1:42:47And he comes up with this idea of the interferometer, which is really what LIGO's design is today.
- 1:42:55The idea is you've got an L-shaped instrument.
- 1:43:01where I have light moving in this direction and light moving perpendicular.
- 1:43:05It's the same setup that Michelson-Morley used back in the late 1800s to show that light was moving in the same speed in both directions, regardless of an ether and all this other stuff.
- 1:43:16That same thing, what if we just made it big?
- 1:43:19Okay?
- 1:43:19Okay.
- 1:43:20What his main contribution, what Rainer Weiss's main contribution was with that paper in the 1970s and 80s was to figure out what are the types of noise that I'm going to run into when I make an instrument of this scale and I want to measure something this precisely.
- 1:43:40Okay?
- 1:43:41And he came up with a list of all of the noise sources that they're going to have to deal with.
- 1:43:46There's going to be seismic noise.
- 1:43:48Right.
- 1:43:48Earthquakes.
- 1:43:49Yes.
- 1:43:49Even an earthquake that's on the other side of the world is going to create low frequency vibrations on the earth.
- 1:43:54At the level that we're trying to measure.
- 1:43:56And that's going to create stuff.
- 1:43:58The waves from the ocean.
- 1:44:02That's going to create noise.
- 1:44:04Cars and trucks, people walking by, that's going to create noise.
- 1:44:08Elephants in the Sahara.
- 1:44:09Yeah.
- 1:44:10Like all the stuff that you could think of.
- 1:44:12He created a list of all the stuff that we would have to come up with.
- 1:44:16And at the end, he had something called quantum noise.
- 1:44:19Okay.
- 1:44:19Which is literally the Heisenberg uncertainty principle.
- 1:44:22Yes.
- 1:44:22Okay?
- 1:44:23Yes.
- 1:44:23It's like there's noise that we're not going to get rid of ever.
- 1:44:27Yes.
- 1:44:28Because that's just how it is.
- 1:44:29Yes.
- 1:44:30And we'll get back to that later because the AI story actually ties into that.
- 1:44:33So he made a list of all of these noise sources and he came up with sort of the ways in which we can make this happen.
- 1:44:43Kip Thorne, on the other hand, he starts doing theoretical calculations of what are the sources in astronomy that could create...
- 1:44:51these gravitational waves, right?
- 1:44:53That we would be able to see.
- 1:44:54How often would these go off?
- 1:44:56Right.
- 1:44:57Given our assumptions about the universe.
- 1:44:59Right.
- 1:45:00And theoretically, is it possible, like that Heisenberg uncertainty limit, what is that limit?
- 1:45:06Right?
- 1:45:06Are we hopeless?
- 1:45:08Or is the Heisenberg uncertainty limit just below the sensitivity that we need to actually find these things?
- 1:45:16Right.
- 1:45:16Okay?
- 1:45:17So you've got these two, Rainer Weiss is spearheading the...
- 1:45:21Approach from the experimental side, and Kip Thorne is spearheading the approach from the theoretical side.
- 1:45:26Yes.
- 1:45:27Okay?
- 1:45:29They think that, you know, maybe this could actually work.
- 1:45:32Okay?
- 1:45:33They're like...
- 1:45:33It's just so crazy.
- 1:45:34They're like, maybe this could actually work.
- 1:45:36The audacity.
- 1:45:36Yeah, dude.
- 1:45:37And in the 70s, they decide to pitch it.
- 1:45:46to the nsf okay national science foundation that's the national science foundation they pitch it to the nsf and the nsf is like this is this we have this amount of money yeah we have this amount of money and what you're saying is something that einstein said wouldn't work
- 1:46:03So they're like, all right, we're going to give you a little bit of funding.
- 1:46:06Why don't you try to get down to these sources of error?
- 1:46:10We're going to give you enough funding where you're not going to find gravitational waves.
- 1:46:13But you can at least start making a prototype to figure out if you can mitigate these sources of error.
- 1:46:20Right, right, right.
- 1:46:21Right, right, right.
- 1:46:22Before we even get down to that 10 to the minus 20, let's get down to 10 to the minus 10.
- 1:46:27All right.
- 1:46:27Where it's like, can you even theoretically like and experimentally make such a...
- 1:46:33instrument.
- 1:46:34Yes.
- 1:46:34Okay?
- 1:46:35So they start going into it...
- 1:46:38Caltech gets a telescope that's about like 90 meters, which is pretty big even then.
- 1:46:45MIT also gets an instrument and they start experimenting with this kind of stuff.
- 1:46:52And it seems promising.
- 1:46:53It seems like they're actually working.
- 1:46:55So then Kip Thorne recruits Ron Draver, who's from Scotland, who had also worked on the early parts of this gravitational wave research.
- 1:47:04And he gets them together and he's like, all right, we're going to pitch this thing.
- 1:47:07This is going to be big.
- 1:47:08It's going to be a big deal.
- 1:47:09All right, boys, we ready?
- 1:47:11So, they start doing it.
- 1:47:13Upper management has turmoil.
- 1:47:16Personal reasons, Ron Draver doesn't get along with this guy Voight, who's also part of the experimental corroboration.
- 1:47:26They just really don't get along.
- 1:47:27You hate to see it.
- 1:47:28You hate to see it, but the two of them are like, I'm out.
- 1:47:31I'm out.
- 1:47:32So now Kip Thorne and Rainer Weiss are just like, okay.
- 1:47:34Okay.
- 1:47:35It's just us again.
- 1:47:35So it's just us again.
- 1:47:36NSF halts funding.
- 1:47:39Oh, God.
- 1:47:40Because they're like, you guys are like headless chickens.
- 1:47:43You have no idea what's going on.
- 1:47:45Um...
- 1:47:46We're going to halt funding and we're going to, if you guys come up with a strategy that actually makes sense and that isn't like petty, then maybe we can talk.
- 1:47:57So that's when Kip Thorne invites Barry Barish, who was at Caltech.
- 1:48:04Okay.
- 1:48:04Barry Barish is, in 1994, he's brought on as the new director of the project.
- 1:48:12And Barry Barish is the reason why producers get the best picture award in the Oscars.
- 1:48:21Okay?
- 1:48:22The Oscars give the best picture award not to the directors or the writers.
- 1:48:27It goes to the producer.
- 1:48:28It's the guy who's, like, putting it all together.
- 1:48:31Barry Barish is that guy.
- 1:48:33This is so random.
- 1:48:35It's so random.
- 1:48:36But he's really an experimental physicist who...
- 1:48:40who does particle physics research.
- 1:48:42He was involved with the superconducting supercollider, which had failed in Texas.
- 1:48:48So he had already learned his lessons there.
- 1:48:51He knew how to deal with people.
- 1:48:52He knew...
- 1:48:54how to figure out what he wanted.
- 1:48:56He knew how to talk to people to get what he wanted.
- 1:48:59And he knew how to get people on board.
- 1:49:01He was the politician of the group.
- 1:49:02He was the guy.
- 1:49:03Yeah, he was the guy who saw the big picture.
- 1:49:06Yes.
- 1:49:06And he's the guy who, when he was brought on...
- 1:49:10He transformed LIGO from a 40-man operation to this thousands of people.
- 1:49:15That is what is required to make that detection.
- 1:49:17He became the wartime CEO.
- 1:49:20Dude, and actually you say that, but somebody actually said to him, like when they were advertising, like who Barry Barish is, at the time, you know, the war in Iraq wasn't very popular.
- 1:49:29Yes.
- 1:49:30And they said, you know, if Barry Barish was in charge of the war in Iraq, it would have been over by now.
- 1:49:36That's how they advertise him.
- 1:49:37He really was the wartime CEO.
- 1:49:39Yeah.
- 1:49:40He was the guy who was like, okay, we're going to build this thing.
- 1:49:43Yes.
- 1:49:44We're going to require two detectors.
- 1:49:46Right.
- 1:49:46We're going to have one in Hanford.
- 1:49:48Yes.
- 1:49:48In Washington State.
- 1:49:49Yes.
- 1:49:49This is actually the original site where we enriched plutonium for the Manhattan Project.
- 1:49:55Now it's being used for this.
- 1:49:56There's going to be another one in Livingston, Louisiana.
- 1:49:59Yes.
- 1:50:00Okay.
- 1:50:00We're going to build them two.
- 1:50:03And he really started this collaboration and it started taking a life of its own.
- 1:50:07And even Kip Thorne and Rainer Weiss were like, thank God for Barry Bearish.
- 1:50:13You know?
- 1:50:13Because he just full steam ahead.
- 1:50:17Like, we're going to build this thing.
- 1:50:19I'm not going to have another failure like the SSC on my hands.
- 1:50:25All credit to him.
- 1:50:26He created that collaboration that built this.
- 1:50:29Every project always needs the operations guy.
- 1:50:32It's funny.
- 1:50:33My dad works in stage one drug discovery.
- 1:50:36And he was over in Scotland.
- 1:50:38And there was a researcher at one of the Scotland universities that had a really interesting fundamental discovery.
- 1:50:43He went to go to VCs to say, hey, give me millions of dollars to make this a thing.
- 1:50:48And they were like, OK, great.
- 1:50:49And he wanted to be CEO.
- 1:50:50And they were like, we need a...
- 1:50:52very bearish we don't need uh you and my dad came in as that operations person who like understands the fundamentals yes but understands the way in which the business world and all these things that are not about the science yes necessarily yeah do matter a lot exactly about these huge large-scale projects yeah yeah when you're talking about that this is something that requires something beyond like knowing how the einstein field equations were right
- 1:51:17Which obviously Barry Barish does.
- 1:51:19He's a trained physicist.
- 1:51:20Right.
- 1:51:20But his real expertise is in this ability to manage.
- 1:51:25Yes.
- 1:51:26A thousand people towards one goal.
- 1:51:29Which is not trivial.
- 1:51:30It's not trivial.
- 1:51:31No.
- 1:51:32And this is the guy who did it, right?
- 1:51:34So fascinating.
- 1:51:35And he, you know, so he started construction.
- 1:51:38Yes.
- 1:51:38He got the money from NSF.
- 1:51:39Yes.
- 1:51:40He convinced NSF this is going to work, guys.
- 1:51:42He got the money from NSF.
- 1:51:44It took five years to build the buildings.
- 1:51:47in Livingston and Hanford in Washington and Louisiana, where, you know, you've got these three kilometer long tunnels, right?
- 1:51:55And the tunnels are so long, they have to be kept completely straight that they're accounting for the curvature of the earth, right?
- 1:52:01Where they have to actually go under a little bit and then get over, right?
- 1:52:05Yes.
- 1:52:06Um,
- 1:52:07In the entire tunnel, you've got to create a vacuum that's better than outer space in the entire three kilometer tunnel.
- 1:52:14And it's like the stupid stuff was actually hard, like creating a tunnel that's better than anything we've ever had.
- 1:52:19Yes.
- 1:52:19Right.
- 1:52:20All of the stuff was completely brand new.
- 1:52:22Right.
- 1:52:22You had to create the best mirror of all time.
- 1:52:26To have these laser interferometers where the laser is going down both and then bouncing back.
- 1:52:31That mirror needs to be near perfect.
- 1:52:33And it is near perfect.
- 1:52:34It's near perfect glass.
- 1:52:35It's the best mirror that we've ever made.
- 1:52:37This mirror, if you left it ringing, right?
- 1:52:39Not that you would want to do this.
- 1:52:40But if you rang it and had it vibrate, that thing would vibrate for 100 million times.
- 1:52:46Before actually stopping.
- 1:52:48Because there's nowhere for the energy to go in this vacuum.
- 1:52:51It just keeps self-propagating.
- 1:52:52Yeah.
- 1:52:53So it just stays within itself and becomes this like perfect spring pendulum thing that just vibrates, right?
- 1:52:59So you've got to create all of these new technologies, right?
- 1:53:03Just to create the environment.
- 1:53:04Just to create the environment.
- 1:53:05And finally, in like 2001, you had LIGO in its first iteration.
- 1:53:12This is when the technology is there to find if you're lucky...
- 1:53:17gravitational waves.
- 1:53:18And this was just a proof of concept to say that, okay, we've reached this far where we've reached the sensitivity level where if we get really lucky and there's like some massive merger that's like right next to us in the galactic neighborhood, we're going to find it.
- 1:53:31They didn't find anything.
- 1:53:32But that's science, right?
- 1:53:34The probability was very low.
- 1:53:36They solved a lot of the engineering problems and this was the crawl, walk, run approach and we're like in between the crawl and walk stage.
- 1:53:42Yeah, they were in the walk stage at this point.
- 1:53:44Got it.
- 1:53:44Okay.
- 1:53:45And then they upgraded LIGO.
- 1:53:48To this LIGO 2.0, to this higher sensitivity.
- 1:53:52And this is right around the 2010s.
- 1:53:55Okay.
- 1:53:55They're upgrading.
- 1:53:58And this is now the run.
- 1:54:00Now we're getting to a point where it is likely that we will catch gravitational waves.
- 1:54:06If it were to pass the Earth, we are now able to detect at a sufficiently small level...
- 1:54:13That it will detect it if it is there.
- 1:54:16That's right.
- 1:54:17Yeah.
- 1:54:18And so then comes the detection.
- 1:54:21Okay.
- 1:54:21This is September 14th, 2015.
- 1:54:23It's at 4.
- 1:54:24Yeah.
- 1:54:25It's at 4.50 a.m.
- 1:54:30Louisiana time, the LIGO computers at both Louisiana and Hanford detect something.
- 1:54:38Okay?
- 1:54:39They detect something and they've got an automated email system that sends it out to like a core group
- 1:54:44of people.
- 1:54:45It's like that scene in movies when they detect aliens for the first time.
- 1:54:48Exactly.
- 1:54:49All the sirens go off, everyone gets an email.
- 1:54:51Wait, wait, wait.
- 1:54:52Is it?
- 1:54:52Is it?
- 1:54:53Yeah.
- 1:54:53In this case, so this was still, they were still in the middle of their run phase, where they were still testing stuff.
- 1:54:59They were like ramping up.
- 1:55:00So the PA system in the actual control room had not been like configured yet.
- 1:55:06So funny.
- 1:55:07So it just, the email went out.
- 1:55:09Right.
- 1:55:09Okay.
- 1:55:09And the people in the control room had no idea.
- 1:55:11That's so funny.
- 1:55:11Okay.
- 1:55:12So
- 1:55:15LIGO had just had this $200 million upgrade, right?
- 1:55:18It was called Advanced LIGO at the time.
- 1:55:20But they were still getting the bells and whistles of this upgrade together.
- 1:55:25And there was a likelihood, but people weren't thinking it was going to happen so soon, right?
- 1:55:29And so the alert goes out, and it's only a handful of data analysts.
- 1:55:35They see this thing.
- 1:55:36There's a guy in Germany.
- 1:55:38There's a guy in University of Florida.
- 1:55:39There's obviously guys at Caltech and MIT.
- 1:55:42They look at this.
- 1:55:45They're like, yeah, right.
- 1:55:46Yeah, right, right, right.
- 1:55:48Yeah.
- 1:55:48Yeah, right.
- 1:55:49Because it's so beautiful.
- 1:55:51Oh, no.
- 1:55:52The signal is like something, you know, like you do simulations and you're like, this is what it should look like.
- 1:55:58And then out comes an email saying, hey, this is what I found.
- 1:56:01It's like, okay.
- 1:56:02It's exactly like the signal.
- 1:56:03It's like exactly like what you're saying.
- 1:56:05So it's like, no, right?
- 1:56:06And all of the big scientists are like, no, this is too good to be true.
- 1:56:09The guy at Caltech actually was just like, I don't have time for this.
- 1:56:14He looked at the email.
- 1:56:15He's like, and then he just went on about because he's got other stuff to do.
- 1:56:19It's advanced LIGO.
- 1:56:20And, you know, his grad students and postdocs are like, did you see the email?
- 1:56:24And he's just like, dude, it's you young people.
- 1:56:26This is not how it works, okay?
- 1:56:29The world is not idealistic.
- 1:56:30Yeah, yeah.
- 1:56:31This is not how it works.
- 1:56:32And it just wouldn't go away.
- 1:56:34Because usually, you know...
- 1:56:37They used to have these things called, they would inject noise, blind injections to see if the system works.
- 1:56:45Yes.
- 1:56:46So maybe there's a guy who's injecting the fake data in there to see if the email alert works.
- 1:56:52Right.
- 1:56:52So they call everybody who's in charge of that.
- 1:56:54And he's like, no, dude, I didn't do that.
- 1:56:55Yeah.
- 1:56:56They go back into the nitty gritty of the data, of the raw data.
- 1:57:00They're like, it's in the raw data.
- 1:57:02Yeah, yeah, yeah.
- 1:57:03And they're like, okay, so now they just start getting real paranoid.
- 1:57:07Yeah, yeah, yeah.
- 1:57:08They're like, who is doing this?
- 1:57:09Yeah, right, right, right, right.
- 1:57:10Okay, who is the evil genius that like went into the Rod?
- 1:57:13And it turns out there's only a handful of people that know the instrument at such a level where they can, they've covered all their tracks.
- 1:57:21Right, right, right, right, right.
- 1:57:22Right?
- 1:57:23And pretty soon they start thinking like, actually, it can't be a single person.
- 1:57:26Yeah.
- 1:57:27Because it happened at both Washington and Washington.
- 1:57:30Louisiana.
- 1:57:31So it must be a bunch of people.
- 1:57:33So now it's like there's a giant conspiracy and everyone's looking at each other like, okay, what's going on?
- 1:57:39Then it turns out, it turns out, so this happened at 4.50 a.m., right?
- 1:57:43That night on September 14th, there were two postdocs outside of the Livingston facility that were trying to test the system.
- 1:57:51With local noise.
- 1:57:53And what they were doing was they got in their car and they were just driving down the arms.
- 1:57:58Oh, yeah, yeah, yeah.
- 1:57:59And just like accelerating and then braking.
- 1:58:02And accelerating and then braking.
- 1:58:03They were trying to see if this would inject noise into the Livingston facility.
- 1:58:08Yes.
- 1:58:09But they had stopped at 4 o'clock because the guy had to catch a flight at 6 a.m.
- 1:58:14He's like, I need to get to the airport.
- 1:58:15Yes.
- 1:58:16So...
- 1:58:17So they call up these postdocs and they're like, what were you doing at 4.50?
- 1:58:21It's like, 4.50?
- 1:58:22Actually, no.
- 1:58:23I know for a fact that I was driving to the airport.
- 1:58:25Yes.
- 1:58:25So it definitely wasn't me.
- 1:58:26I was nowhere near.
- 1:58:28And also, like, why would that happen at the Washington facility?
- 1:58:31But at this point, everyone's, like, real paranoid, right?
- 1:58:34So they're trying to be their own worst enemy, trying to see who faked the signal.
- 1:58:39Because this signal is just too good.
- 1:58:41Yes.
- 1:58:41Right?
- 1:58:41Like, God isn't this kind.
- 1:58:43Yes.
- 1:58:45And at the end of the day, it's like, okay, is this a prank?
- 1:58:49All of the dudes that could have done this get in a room.
- 1:58:52And they're just like, all right.
- 1:58:54Did you do it?
- 1:58:54Did you do it?
- 1:58:55What about you?
- 1:58:55What about, did you do it?
- 1:58:57And everyone's like, no, we didn't do it.
- 1:58:59And it's like, shit.
- 1:59:01Silas descends across the room.
- 1:59:02Yeah, it's like, dude, what?
- 1:59:04Okay, so then...
- 1:59:06You say, okay, so nobody did this.
- 1:59:09And it's kind of like that Sherlock Holmes quote, right?
- 1:59:11Where it's like, when you eliminate the impossible, what remains, however improbable is the truth, right?
- 1:59:18Is the reality.
- 1:59:20They're like, dude, this is crazy.
- 1:59:21So now they start having, they have a blind data augmentation technique where they have a blind team that tries to decipher...
- 1:59:37How likely is this to be chance that the detectors just like randomly, maybe there was an earthquake that was right in the middle that like arrived at the same time or something, you know, or like the detectors themselves like did this like fluctuation randomly.
- 1:59:54How likely is that?
- 1:59:55So they start going down this rabbit hole of like, okay, what if, how much of this is a fluke?
- 2:00:00Because you got to figure out a confidence, right?
- 2:00:02Remember the confidence is five sigma.
- 2:00:05So these guys are in charge of that.
- 2:00:08And they go through and there's this big unblinding party where they open the box.
- 2:00:15It's like a gender reveal.
- 2:00:17So what happens is they do all of their analysis without actually looking at the real data.
- 2:00:22Got it.
- 2:00:22And then they open the box and now they take the real data and say, okay, given our analysis, where does the – given our distribution, where is the real data?
- 2:00:30Okay.
- 2:00:31They don't even know.
- 2:00:33with the real data.
- 2:00:34It is, right, right.
- 2:00:34Okay?
- 2:00:35They've been doing this blind.
- 2:00:36So they have this unblinding party where they open the box, and everyone knows when this is going to happen.
- 2:00:43And the party happens, you know, their Zoom meetings are only set up for, like, 50 people, but, like, everybody in the collaboration shows up.
- 2:00:55So it crashes.
- 2:00:56Right, right.
- 2:00:57And so then they're scrambling, they're like, okay, we've got to get the Zoom meeting up, finally get it up.
- 2:01:02They unblind.
- 2:01:02And this is well above Five Sigma.
- 2:01:04Oh, my God.
- 2:01:05And everyone is like, that's when the champagne comes out.
- 2:01:08Yeah, yeah, yeah.
- 2:01:09That's when they're like, wow, we got him.
- 2:01:10We got him.
- 2:01:11We got him.
- 2:01:11We got him.
- 2:01:12We got him.
- 2:01:13We got him.
- 2:01:14a single gravitational wave that was like so ridiculous, right?
- 2:01:19Because had those, had those two postdocs been going on their thing for like through four 50, we wouldn't have, we wouldn't have caught this thing.
- 2:01:29It's such a, it's, it's now become like part of like the LIGO lore of like, and those two postdocs are now like famous because like, like they decided to like call it early at like four o'clock in the morning, you know, it's so cool to think about that.
- 2:01:44Like,
- 2:01:45Yeah, like we were listening to...
- 2:01:49You know, gravitational radiation from billions of light years away from two black holes that merged.
- 2:01:55And to think about the incredible, like, sensitivity of this instrument.
- 2:02:00We really haven't gotten into just how incredible this is.
- 2:02:03I threw around a number like 10 to the minus 20.
- 2:02:05Yes.
- 2:02:06Right?
- 2:02:07To give you a sense of how small that is, that's like measuring the distance from the Earth to the sun.
- 2:02:16And then you add an extra atom.
- 2:02:19Ah, yeah, yeah.
- 2:02:20To that distance.
- 2:02:20To that distance.
- 2:02:21Yeah, yeah, yeah.
- 2:02:22That's stupid.
- 2:02:23Yeah, no, I don't...
- 2:02:24This is where...
- 2:02:25This is why Einstein was like, no.
- 2:02:26Yeah, no.
- 2:02:27Because it's so outrageously arrogant for us to think... To think that we could measure that.
- 2:02:34We could measure a disturbance at a degree that is so small...
- 2:02:43And be able to make it verifiable.
- 2:02:45Yeah, yeah.
- 2:02:4610 to the minus 19 meters is what we actually did, which 10 to the minus 15 is a proton.
- 2:02:52So this is 10,000th the distance of the diameter of a proton, the size of a proton.
- 2:02:58So we have these two 3-kilometer tunnels on different sides of the country.
- 2:03:02And we're measuring a difference.
- 2:03:03Of a tenth of a proton.
- 2:03:05No, a 10,000th.
- 2:03:05A 10,000th.
- 2:03:06Of a proton.
- 2:03:07Yeah.
- 2:03:09Right?
- 2:03:10Like the detectors themselves are made out of atoms that are made out of
- 2:03:15Protons.
- 2:03:16And the protons are like a ten thousandth the size of the atom.
- 2:03:18And now you've got...
- 2:03:20So it's an incredible achievement, right?
- 2:03:23It took a thousand people.
- 2:03:25Experimentalists, theorists, NSF bet big on this.
- 2:03:30The National Science Foundation really like bet the farm on this thing working.
- 2:03:35And it worked, right?
- 2:03:36It took decades.
- 2:03:37Yeah.
- 2:03:37And we got them.
- 2:03:38And we got them.
- 2:03:41It's a new way to look at the universe, right?
- 2:03:46Before we were limited to electromagnetic radiation.
- 2:03:49We had pulled all the stops when it comes to electromagnetic radiation.
- 2:03:52We'd gone all the way from radio, which is long wavelength, all the way from radio to infrared, microwave, infrared, visible, the optical spectrum, ultraviolet, X-ray, gamma ray.
- 2:04:04We've got gamma ray telescopes that are looking at gamma ray bursts.
- 2:04:09We've done particle detectors, right?
- 2:04:11We've had neutrino detectors, cosmic ray detectors.
- 2:04:15Many of which we've talked about previously on this podcast.
- 2:04:17On this podcast.
- 2:04:18And now we were listening to the universe, not just looking at it, right?
- 2:04:22We were listening to the space-time ripples.
- 2:04:25And what's crazy is like the ripples that come in –
- 2:04:29especially for this first discovery, was in the human audible range.
- 2:04:33And so you could actually just hook up an amplifier and hear it.
- 2:04:36And hear these black holes coming in.
- 2:04:38It would be a chirp because the frequency would increase with time.
- 2:04:42So it would go, like that.
- 2:04:46Because the black holes are coming together and as they get together, conservation of angular momentum, they're going to speed up.
- 2:04:53And as they speed up, they're going to release higher frequency gravitational waves.
- 2:04:57And so the...
- 2:04:59the signal that we were seeing.
- 2:05:01And that's why these guys were like, there's no way this is real.
- 2:05:03Right.
- 2:05:04Because if you look at the spectrogram, the frequency versus time, you see this characteristic thing.
- 2:05:11It's like exactly like in the simulations.
- 2:05:13You're just going, come on.
- 2:05:14There's no...
- 2:05:15There's no way this is real.
- 2:05:18Right?
- 2:05:18And so it took them five months from detection to, like, being confident enough where they were like, all right, let's announce it.
- 2:05:26Because as we've talked about, you don't want to put something out that, you know, is not prepared for – because everyone's going to come at you and not.
- 2:05:34Yes.
- 2:05:34Yeah.
- 2:05:35And especially because in the past, like with Weber and his gravitational wave detector, right, those were fake.
- 2:05:41But like this, at this point, it's like they had done all of the work and the International Corral Collaboration had done all the work.
- 2:05:47They really weren't very confident until they saw the second one.
- 2:05:51They saw a second one and they're like, oh, okay, this is real.
- 2:05:54We're like literally listening to the universe.
- 2:05:56Then the Italian crab collaboration, Virgo, came online.
- 2:06:00Virgo is a detector very similar to LIGO.
- 2:06:03It came online and the three of them, so the two LIGOs and Virgo, detected a neutron star merger.
- 2:06:10And that was a big deal because now that you've got...
- 2:06:12Three, you can actually do triangulation.
- 2:06:15Triangulation, right.
- 2:06:15Okay?
- 2:06:16With only two detectors, the only signal you really have is the time difference between the arrival here and the arrival here.
- 2:06:24Now, gravitational waves propagate at the speed of light.
- 2:06:27So, for example, if they both arrived at the same time, then you know that it's on this plane.
- 2:06:33Yes.
- 2:06:33Right?
- 2:06:34And it came from this angle.
- 2:06:35Yes.
- 2:06:36But if it arrived here before and then here later, then it came from this angle.
- 2:06:41Yes.
- 2:06:41Right?
- 2:06:41And you get this sort of arc in the sky of where it could have come from.
- 2:06:46Right, right.
- 2:06:46But that's a giant arc.
- 2:06:48Arc, right.
- 2:06:48Okay?
- 2:06:49If you've got three, then you've got...
- 2:06:52Three arcs.
- 2:06:52You've got an arc here, an arc here, and an arc here.
- 2:06:55And wherever those three arcs intersect has got to be the spot that it came from.
- 2:07:00So then once we had the signal from all three, we could point our telescopes to it and actually see what is generating it.
- 2:07:07The gravitation.
- 2:07:08And that was crazy because what would end up happening is the gravitational wave comes in first because there's nothing that's impeding gravitational waves.
- 2:07:16It's just going.
- 2:07:17Neutrinos actually came in right after because neutrinos also, they're very, they don't interact with anything.
- 2:07:23So they're just coming through.
- 2:07:25Yes.
- 2:07:25Light was actually later because light was interacting with all the stuff.
- 2:07:30The stuff.
- 2:07:31And then there was a tiny delay.
- 2:07:32Yes.
- 2:07:33And so we had just enough time to point our telescopes to this thing and see the neutron stars colliding.
- 2:07:39And that's where we got our first sense of where these heavy elements, the precious metals, like platinum, gold.
- 2:07:47These guys, they actually come from these neutron star mergers.
- 2:07:51More than like supernovae and things like that.
- 2:07:53It's from these neutron star mergers where we get the gold that's in my wedding ring and things like that, right?
- 2:07:58You know what's so... And so it opened up on...
- 2:08:01It's just so cool.
- 2:08:03A great story to look back and listen to is our story covering Ice Cube, the neutrino detector in Antarctica, because it kind of explains this neutrino travel time and light travel time and why there's a difference between those two, which the implications of which...
- 2:08:18dovetail with this gravitational wave detection first neutrino right after light then shortly after why is that happening go back and listen to our ice cube story because we kind of touch on the mechanics exactly of light traveling and neutrinos traveling yeah i just it's funny because all these things again these are just they're all connected
- 2:08:38Yeah, they're all connected.
- 2:08:39And now we've got a fourth one, Kagura, in Japan.
- 2:08:43We did a story on how all four found the largest black hole merger.
- 2:08:48That was another story on the podcast.
- 2:08:50So now we've got four, so we can triangulate even better.
- 2:08:53I think India and Australia are in plans to make their own gravitational wave detectors.
- 2:08:59So now we're going to have this entire collaboration.
- 2:09:03And now...
- 2:09:04The trick is, so we've discovered gravitational waves.
- 2:09:08We can now listen in on gravitational waves.
- 2:09:10We're getting signals at about the rate of like tops like five a year.
- 2:09:14Yes.
- 2:09:16In the volume of the universe that we can listen to.
- 2:09:18Yes.
- 2:09:18Right before it gets like so small that we can't listen to it.
- 2:09:21Yes.
- 2:09:22Yes.
- 2:09:23So they're at some proximally close location.
- 2:09:26Yeah, yeah, yeah.
- 2:09:27They're close enough where the gravitational wave hasn't dissipated so much that we're not sensitive.
- 2:09:33Now, if we make it more sensitive, then we can expand that volume, right?
- 2:09:38We can actually expand the radius, and the volume goes up by r cubed.
- 2:09:43Yes, yes.
- 2:09:43So just even 10% to 15%.
- 2:09:46Difference in the radius amounts to twice the volume, right?
- 2:09:50Because you're going to cube that.
- 2:09:51Yes.
- 2:09:52So now the challenge is, how do we make LIGO better?
- 2:09:56Where we're not only seeing a larger volume, but the stuff that we're seeing, we're starting to notice all of the overtones and all of the stuff that makes a musical note great, right?
- 2:10:09If you've heard like, you know, the...
- 2:10:12The note that comes out of your phone when you're trying to tune your guitar, that's a pure note.
- 2:10:18It's a C or an A.
- 2:10:19Not very interesting.
- 2:10:21Right?
- 2:10:21But a piano, why is a piano note interesting?
- 2:10:24It's because there's all of these overtones and nice characteristics from the piano itself.
- 2:10:33that give it that beauty.
- 2:10:35Would a way to frame it, like the texture that the physical piano adds to the tone itself, which is a manifestation of its physical construct, like how it physically exists on all of that.
- 2:10:48Yes, yeah, exactly.
- 2:10:49Like a guitar string playing the C is different from a piano string playing the C, is different from a violin resonating at C. And it's all because of that texture of the note.
- 2:11:03characteristics of that musical note.
- 2:11:06The overarching note, if you were to do a physics...
- 2:11:11breakdown of it, the overarching node is still going to be that base C. Yes.
- 2:11:15But all that stuff on top is what gives it the beauty.
- 2:11:18So the question is, how do we make LIGO see that beauty?
- 2:11:23That piercing.
- 2:11:23In the gravitational wave.
- 2:11:25Without any of that extra texture.
- 2:11:26Instead of seeing just the C. Oh, seeing it in its...
- 2:11:29I got it.
- 2:11:30You know what I'm saying?
- 2:11:30I understand what you're saying.
- 2:11:31Instead of seeing just the node, which is what it's good for right now, we're seeing I would do it rip, but now there could be stuff on top that would give us characteristics about...
- 2:11:41the environment that the black holes were in, where the neutron stars were in, right?
- 2:11:46How long they've been going at it.
- 2:11:48All of this other stuff.
- 2:11:50All of the other characteristics.
- 2:11:51And that's where the recent paper that's out of Caltech and DeepMind comes in.
- 2:11:57Got it.
- 2:11:57Okay?
- 2:11:58What they're trying to do is push the sensitivity of LIGO to levels...
- 2:12:04that were unimaginable before.
- 2:12:07I mean, LIGO itself is unimaginable.
- 2:12:08Unimaginable.
- 2:12:09Right?
- 2:12:10But now they're taking it a step further with the use of AI.
- 2:12:14Okay.
- 2:12:16Okay.
- 2:12:16So why do we need AI, right?
- 2:12:20LIGO has this problem that's called a wall of noise.
- 2:12:23Okay?
- 2:12:24There's a wall of noise right at 10 to 30 Hertz.
- 2:12:27Okay?
- 2:12:28Above 30 Hertz, they're pretty good.
- 2:12:31Okay?
- 2:12:33But below 30 hertz at these low frequencies, they're having a real issue.
- 2:12:37There's too much noise?
- 2:12:38There's too much noise.
- 2:12:39Okay.
- 2:12:40The noise is coming from seismic effects.
- 2:12:45Like whenever you have a giant earthquake, the earth rings.
- 2:12:50in these low frequencies and it rings for a while.
- 2:12:53Okay.
- 2:12:54On the other, also the moon tugging on the oceans creates these tides and the wave action itself is ringing around the earth creating, so we're pushing that level.
- 2:13:05Got it.
- 2:13:06And we're trying to get rid of that.
- 2:13:08Now, what they've tried so far is something called feedback control.
- 2:13:15and you've actually used feedback control in your own life, you have AirPods, right?
- 2:13:20Yes.
- 2:13:20The new AirPods, they've got noise cancelling.
- 2:13:22You've probably used noise cancelling headphones.
- 2:13:25The way noise cancelling headphones work is they've got a feedback loop that senses low frequency noise, and then that sensor then counteracts that noise and destructively interferes with it to cancel it out.
- 2:13:41Mm-hmm.
- 2:13:42Is this creating an interference pattern so it cancels it out?
- 2:13:46Yes, exactly.
- 2:13:47It's creating an interference pattern so that it cancels it out.
- 2:13:50This works really well on the airplane because the airplane is a low frequency hum, right?
- 2:13:54Yep.
- 2:13:55That's the ambient noise.
- 2:13:56That makes sense because I just was on a flight and I was like, these are really good.
- 2:14:01Yeah, the reason why is because the airplane is low frequency and you can do that with low frequency because with low frequency you have enough time to respond with your control system.
- 2:14:10Right.
- 2:14:10Right?
- 2:14:11The time scale of that vibration is slow enough where you can actually like counteract.
- 2:14:15Yep.
- 2:14:15But now comes a tradeoff.
- 2:14:18Right?
- 2:14:18There's a tradeoff because aggressive control at these low frequencies means you're going to introduce noise from the control system itself.
- 2:14:27Yes.
- 2:14:28At higher frequencies.
- 2:14:29That makes sense.
- 2:14:30Right?
- 2:14:30Now, for noise-canceling headphones, it's fine.
- 2:14:33You might sometimes, if you're really careful, you'll hear a really high-pitched tone in your noise-canceling.
- 2:14:39Yeah, yeah, yeah.
- 2:14:39If you're, like, really trying to find it.
- 2:14:42Right, right.
- 2:14:43But what you're really worried about is the loud, low frequency.
- 2:14:47Right.
- 2:14:47And so you're getting rid of that, you're happy on an airplane.
- 2:14:49The level of precision we need at headphones is a very different scale than what we're trying to do when we talk about detection at this level.
- 2:14:55Yes.
- 2:14:56At this LIGO's level...
- 2:14:58Right, right.
- 2:14:59Now even that is annoying.
- 2:15:01Yeah.
- 2:15:02Right?
- 2:15:03It was not annoying because that's what allowed us...
- 2:15:05The feedback control on the mirrors themselves, you've got these actuators on the mirrors because the mirrors themselves have noise, right?
- 2:15:12Yes.
- 2:15:12They can be tilted in a certain way.
- 2:15:14They can be up and down.
- 2:15:16If there's some seismic effect, then the mirrors can wobble.
- 2:15:20And then the wobble is going to be greater than the...
- 2:15:23you know, 10 to the minus 19 meters that you're trying to do.
- 2:15:27It's incredibly ridiculous, right?
- 2:15:29How still you're trying to make these mirrors.
- 2:15:31Yes.
- 2:15:31Okay.
- 2:15:32So in order to actually get that,
- 2:15:37We use these feedback control mechanisms, right?
- 2:15:40But the feedback control mechanisms inject high-frequency noise.
- 2:15:44The target would be to get rid of that high-frequency noise and be limited by only quantum noise by the Heisenberg-Uncernib principle.
- 2:15:51From that list that we talked about earlier.
- 2:15:54Yes.
- 2:15:54We want to be limited by the universe itself, right?
- 2:15:57And the laws of quantum mechanics.
- 2:15:58Yes.
- 2:15:59The quantum mechanics noise comes in two forms.
- 2:16:02There's shot noise, which is, you know, the laser itself...
- 2:16:06I mean, at this rate, we're talking about photons hitting the mirror.
- 2:16:10And the photons are going to hit the mirror at random arrival times.
- 2:16:14So that's called shot noise.
- 2:16:16Because the difference in arrival time is noise.
- 2:16:18The difference in arrival time in the photon is enough to cause the shot noise.
- 2:16:22Oh, my God.
- 2:16:23That's the level that we're working at with these mirrors.
- 2:16:26These mirrors are like kilograms big.
- 2:16:28And they're worried about tiny photons hitting it at random times.
- 2:16:32That's what we're complaining about.
- 2:16:33Yes.
- 2:16:33About.
- 2:16:34The other limit is quantum back action, which is not only is the photon coming at random times, but when it hits and goes back, it's going to transfer momentum.
- 2:16:45Yeah, to the mirror.
- 2:16:46And the mirror is going to wobble because the photon has a reaction force.
- 2:16:51Right.
- 2:16:51And because there's multiple points, the reaction force is happening everywhere.
- 2:16:54Yeah.
- 2:16:54And it's like, it's like, it's like, so...
- 2:16:56So that we can't control because the universe is like, you're doing too much.
- 2:17:00Yeah, yeah, yeah.
- 2:17:00You know, this is admin privileges only.
- 2:17:03Yeah, yeah, yeah, exactly.
- 2:17:05The fact that you're getting this far already, I'm like, wow.
- 2:17:09But yeah, let's slow down.
- 2:17:11But that's where we're trying to get to.
- 2:17:13Makes sense.
- 2:17:14To having that being the only remaining noise in the data set.
- 2:17:17It's like, then it's like, okay.
- 2:17:19And so that's where this scientific AI comes in.
- 2:17:23Okay.
- 2:17:24Okay.
- 2:17:24What these guys are trying to do at DeepMind and at Caltech is they're trying to quiet LIGO's control systems using a radically new AI approach.
- 2:17:34Okay.
- 2:17:34Okay.
- 2:17:34And this isn't the first time that AI has been sort of used to, you know, help scientific collaboration.
- 2:17:41Yes.
- 2:17:41But most of the time AI...
- 2:17:43has sort of played the role of a data analyst.
- 2:17:45Right.
- 2:17:45Right?
- 2:17:46After the data has been collected.
- 2:17:48Like we've talked about the Vera Rubin telescope, right?
- 2:17:51Once the Vera Rubin takes all of these pictures, AI can go through and sift through and find asteroids that move around or new transient effects from supernovas and things like that.
- 2:18:00AI can also be used in cosmology for running simulations faster for the universe's evolution and things like that.
- 2:18:07But this...
- 2:18:08idea of using AI actively in the data acquisition and in the experiment itself is kind of new.
- 2:18:14It's not without precedent.
- 2:18:16CERN uses it at the Large Hadron Collider.
- 2:18:19They actually use AI algorithms and machine learning systems to actually trigger whether to keep...
- 2:18:27a certain particle scatter data or whether to discard it.
- 2:18:31So there's a machine learning algorithm that basically makes this split second decision on whether a particle collision and the shower that came afterwards is interesting or whether it's something that you don't want to save.
- 2:18:44The amount of particle collisions that are happening are astronomical.
- 2:18:49I mean, even though CERN's data storage capabilities are insane, it's not going to be able to save everything, right?
- 2:18:55So you need some way to sift through that, and machine learning is doing that.
- 2:18:59It's also accelerating simulations on these particle systems.
- 2:19:02But this approach from LIGO is another thing in that vein of using AI actively in the experiment itself.
- 2:19:09Yep.
- 2:19:10So what they figured was, okay, we're trying to keep the mirror as still as possible.
- 2:19:13Yes.
- 2:19:14Okay?
- 2:19:15Why don't we use a reinforcement learning agent to train and devise its own strategy on how to keep the mirror stationary?
- 2:19:24And it's great that we just did an episode on reinforcement learning.
- 2:19:27Yes.
- 2:19:27Because it goes very deep into the structure of why.
- 2:19:30This was in our DeepSeek coverage.
- 2:19:33Yeah.
- 2:19:33Just did these two papers on how they went from human feedback to...
- 2:19:38Yeah, to just pure reinforcement learning.
- 2:19:40And so the point about pure reinforcement learning here is that you as the human who is designing the AI system are not giving it feedback about whether the answer that it's going down is correct or incorrect, which enables – I think the point here is like novel ideas about how to solve the problem.
- 2:19:58That's not limited by our perspective or our perceptions.
- 2:20:00Exactly.
- 2:20:01Yeah, exactly.
- 2:20:02In this case, the reinforcement learning agent is going to just try all these different strategies, see what worked, and then go down that path and make that strategy better.
- 2:20:12And that's exactly what they did.
- 2:20:13They created a reinforcement learning agent.
- 2:20:15They gave it an environment, which is this highly accurate computer simulation of LIGO.
- 2:20:21I mean, they can't give it LIGO.
- 2:20:22LIGO is busy trying to listen.
- 2:20:25So they made a computer simulation of LIGO, and that's the environment that this agent is now playing around with.
- 2:20:31Yes.
- 2:20:32The current mirror was the state, like whatever the mirror was.
- 2:20:35And then the action it could take was, you know, moving it with all the actuators.
- 2:20:39Yes.
- 2:20:40And it could play around and figure out how to keep this mirror as still as possible.
- 2:20:44Yes.
- 2:20:44And you can inject noise into it and see how it would do.
- 2:20:46And you can do it...
- 2:20:47Hundreds of thousands, millions of times and different parameters.
- 2:20:51Yes, different parameters.
- 2:20:52And you can see and you can give it a reward every time it does a good job.
- 2:20:56And you can penalize it every time it does a bad job.
- 2:20:59In this case, the process of actually rewarding it was actually kind of cool.
- 2:21:04Because you can't just be like, keep it still.
- 2:21:06Yeah.
- 2:21:07That's a little too much.
- 2:21:09Freedom.
- 2:21:10So what they did was they created three distinct bands in the frequency space.
- 2:21:15They called this approach the DLS approach, which is deep loop...
- 2:21:20Shaping.
- 2:21:21Loop shaping, meaning this kind of control paradigm where you're worrying about the frequency response of your system and deep from deep learning.
- 2:21:28Yes.
- 2:21:29Okay, so deep loop shaping.
- 2:21:30What they did was they got that frequency band of all of the noise and they split it up into three different categories.
- 2:21:37So there's a low pass filter for stuff that's below three hertz.
- 2:21:41Three hertz, meaning three cycles per second.
- 2:21:44And that's where all of the seismic disturbances, your sort of...
- 2:21:54the tides and all of this stuff comes up at low frequency.
- 2:21:56For people who work in music, this is like all the bass stuff.
- 2:22:00All the bass, yes.
- 2:22:01This is the bass.
- 2:22:02Right, okay.
- 2:22:03Yeah.
- 2:22:04And with that bass stuff, it basically said, you're going to get aggressive stabilization.
- 2:22:10We want to teach you aggressive stabilization.
- 2:22:13You get a high reward.
- 2:22:14If you eliminate the bass noise.
- 2:22:16Okay, great.
- 2:22:18Then there's the bandpass filter of 8 to 30 hertz.
- 2:22:20That's the part that we're trying to really optimize.
- 2:22:22Okay.
- 2:22:25That's where the control noise comes in from these guys.
- 2:22:28And so what they gave was a penalty, a negative reward.
- 2:22:33If it got any noise in that 8 to 30.
- 2:22:37In that 8 to 30 hertz.
- 2:22:39Okay.
- 2:22:39The low part was just reward.
- 2:22:42Yes.
- 2:22:42This has a negative reward.
- 2:22:44Okay.
- 2:22:45It's like penalizing heavily.
- 2:22:47And the high pass filter also penalizing.
- 2:22:49Okay.
- 2:22:50But different weights.
- 2:22:51Yes.
- 2:22:51And then the crucial thing what they did was they multiplied the rewards at the end.
- 2:22:55Mm-hmm.
- 2:22:57to give a final reward instead of adding.
- 2:23:00A lot of reinforcement learning techniques have added with additive reward.
- 2:23:05Nowadays, people are slowly foraying into this idea of multiplicative.
- 2:23:09The problem with multiplication of reward is it can easily blow up.
- 2:23:13Right.
- 2:23:14And like be very dangerous.
- 2:23:15Right.
- 2:23:16But there's come mitigation strategies against that.
- 2:23:18Got it.
- 2:23:19And so now with multiplicative reward, you force the agent to perform well on all three tasks.
- 2:23:26Right.
- 2:23:26Not just one.
- 2:23:27Right.
- 2:23:27Because you could have one in the summation model.
- 2:23:30You can have one that's super, super high.
- 2:23:32Yeah.
- 2:23:32That kind of drowns out.
- 2:23:34Yeah.
- 2:23:35And it's just like zero noise in the base.
- 2:23:36Right.
- 2:23:37But then you're just like...
- 2:23:38Completely wrecked in the other ones.
- 2:23:39That's actually interesting.
- 2:23:40Through the math, it sort of forces equal distribution of optimization.
- 2:23:45Exactly.
- 2:23:45Yeah.
- 2:23:46Yeah, that's exactly right.
- 2:23:47Interesting.
- 2:23:47And so they tested it on this digital twin that they had made of LIGO, and it worked really well.
- 2:23:53And they're like, okay, this is pretty cool.
- 2:23:55They injected noise, and it was still able to do it.
- 2:24:00And then for one hour, they were given...
- 2:24:03time time oh yeah you know ligo's real busy you gotta check the schedule i think we can get you one hour yeah they got so they got one hour on ligo um and they installed this this device on ligo and it was a great success the ai controller stably managed
- 2:24:21these mirrors for an hour and the amount of noise on the actual thing the physical physical livingston observatory they they they got the controls for the actuators yes they attached it to this agent they're like that was the driver of the bus and now now you you take the wheel let's see what you do and for over an hour in real world conditions yes and the noise was like shot like it it like saying it's
- 2:24:49Like an insane amount.
- 2:24:52Right?
- 2:24:53And it's like, oh.
- 2:24:54Yeah.
- 2:24:55This is the future.
- 2:24:55This is the future.
- 2:24:56Yeah.
- 2:24:57There's so many...
- 2:24:58I could talk about this for a minute.
- 2:25:00They were getting down to quantum level, dude.
- 2:25:02They got down to that quantum limit.
- 2:25:04They were saying the noise level was well below the design goal, being 10 times quieter than the quantum back-to-back action limit.
- 2:25:11Holy moly.
- 2:25:13And so now, now that they did it on Livingston, now they're going to make it even better, put it on both LIGOs.
- 2:25:18They're going to give it to Virgo, put it on theirs.
- 2:25:20Give it to Chagra, put it on theirs.
- 2:25:22And then now we're going to have four...
- 2:25:24gravitational observatories that are limited by quantum noise.
- 2:25:32It's so incredible.
- 2:25:33I think the efficacy and impact.
- 2:25:38I mean, there's so many levels to this.
- 2:25:39One is our ability to create a digital twin to such levels of fidelity that it translates from a simulated environment to the real world environment.
- 2:25:49So well.
- 2:25:49So well.
- 2:25:50Like that in and of itself.
- 2:25:51Yeah, that itself is great.
- 2:25:54Thinking about the reward model and using reinforcement learning and finding a way to get that reinforcement learning really tight such that the optimization that it ended up with, again, gets to that degree.
- 2:26:08And it's basically we're just going to do a software patch.
- 2:26:11I know that's not literally the translation.
- 2:26:12Kind of.
- 2:26:14Existing hardware.
- 2:26:15Hardware does not change.
- 2:26:16Yeah.
- 2:26:17At all.
- 2:26:17At all.
- 2:26:18And every one of these four detectors globally is just going to get this 10x noise reduction optimization benefit.
- 2:26:25Just a relatively snap of a finger given the time scale it took to the Lego.
- 2:26:30To be fair, the noise reduction is more than 10x.
- 2:26:33It's okay.
- 2:26:33Wow.
- 2:26:34Right?
- 2:26:34It's like from before to now, the noise reduction is like 10 to the 3.
- 2:26:38Oh, my gosh.
- 2:26:38It's just that now we're below the quantum noise by 10x.
- 2:26:42Got it.
- 2:26:42So now the limiting is the quantum noise.
- 2:26:46And that we just, I don't know what to do with that, right?
- 2:26:48This is so insane.
- 2:26:50It's insane.
- 2:26:51And this has actionable consequences on what LIGO can see.
- 2:26:55For one, it's more sensitive, so it's got a larger volume of the universe.
- 2:26:58But the other, it's now sensitive to a new frequency band, this 10 to 30 hertz, right?
- 2:27:04Which was not accessible to us before.
- 2:27:05And this is exactly where you have intermediate black holes.
- 2:27:10intermediate mass black holes.
- 2:27:12And this is going to help us solve a huge... Below supermassive?
- 2:27:16So it's like smaller in size.
- 2:27:17Exactly.
- 2:27:18Smaller in size from supermassive, but larger in size from stellar mass.
- 2:27:22Ah, got it.
- 2:27:23There's been this contention in the black hole physics community about where the hell are the rest of the black holes.
- 2:27:30We see a bunch of stellar mass black holes, right, with LIGO and things like that.
- 2:27:34We obviously see supermassive black holes at the center of galaxies.
- 2:27:38But...
- 2:27:39The black hole mass gap is what it's called.
- 2:27:42Yeah, yeah, yeah.
- 2:27:42This gap between supermassive and stellar mass, this intermediate mass black holes, where are they?
- 2:27:50Yeah, yeah.
- 2:27:50Well, now LIGO is going to be sensitive to those intermediate mass black hole mergers because those would happen slower.
- 2:27:58than the stellar mass.
- 2:27:58The stellar mass, they can get closer together.
- 2:28:02And if you get closer together, you speed up, right?
- 2:28:04Neutron stars as well.
- 2:28:05The closer you get, the more you speed up.
- 2:28:07So with the neutron stars, you can actually start observing them earlier in their decay cycle, right?
- 2:28:14Where before you had to sort of wait till they got really close to create these big fast...
- 2:28:19gravitational waves now you can spy on them from the very beginning and see them speed up and get closer and closer together the idea and just to make sure i'm kind of understanding the idea is part of the spinning and the closeness is what it is what dictates the size of the gravitational wave that's being sent and this is where we talked about they have to be really really big when we started for us to see them because we couldn't detect at this range yeah by having this range
- 2:28:48We can detect fainter gravitational waves, which one of the sources being these intermediate black hole.
- 2:28:54Yeah, and the other one being the neutron star mergers early on.
- 2:28:57Earlier, earlier in its... Yeah, so now, like, you can imagine, you can have an early warning system that something's going to happen, but minutes in advance.
- 2:29:06Right.
- 2:29:06Not, like, fraction of a second.
- 2:29:07Right.
- 2:29:08Because the gravitational wave itself lasts, the ones that we've seen, last, like, fractions of a second.
- 2:29:14Right.
- 2:29:14Because that's when they get close enough to actually get big enough.
- 2:29:17the waves get big enough for us to see.
- 2:29:19Yes.
- 2:29:19But like now we can have a minutes long advance.
- 2:29:23Yes.
- 2:29:23Where now, even the James Webb with minutes, James Webb could drop what it's doing and point.
- 2:29:31And we could see it at the moment.
- 2:29:33And so this is a combination of being able to hear the universe and see the universe.
- 2:29:37And this sort of new level of accessibility allows us to combine both of these...
- 2:29:43tool sets in combination to be able to now not only hear it, have a window of time that's long enough that any number of different Earth-based or space-based detection platforms that are looking at infrared or optical could look in the direction of the source because we have four locations.
- 2:30:02Yeah.
- 2:30:13Events.
- 2:30:15Oh, my goodness.
- 2:30:16It's like, yeah, we really are living in a golden age of...
- 2:30:22time domain astronomy right we had a golden age of astronomy in general but it's like we were looking at still pictures right right right and now and now the universe is dynamic and we have access to that extra dimension which is time passing and us then seeing the transition of these objects over time with really really high fidelity
- 2:30:43Yeah.
- 2:30:43We have early warning systems now.
- 2:30:45We've got the Vera Rubin that's going to find random stuff.
- 2:30:48Yes.
- 2:30:48Yeah.
- 2:30:48And this is another.
- 2:30:49Now that we have this 10 to 30 hertz band that we're sensitive to, we got that unknown unknowns coming back again, right?
- 2:30:57This is, I think what's so interesting, this time domain astronomy point is it's like we're turning on the light for the first time.
- 2:31:06We've sort of been like having candlelight in this.
- 2:31:08We've been doing flashlights.
- 2:31:09Flash photographers.
- 2:31:09Flash photographers, right, right.
- 2:31:10In this like small window.
- 2:31:12And so not only do we have a larger window, we also now have this ability to see things in time.
- 2:31:19Which again means our ability to understand what's actually happening in the universe around us is like right now, today.
- 2:31:26Like not 20 years ago, not 50 years into the future.
- 2:31:30We talk about Varouba.
- 2:31:30It's going to be putting out data every three days globally in real time.
- 2:31:34That's going to see things we've literally never seen before.
- 2:31:37Yeah.
- 2:31:37And lots of it.
- 2:31:39Like, lots of it.
- 2:31:40This is...
- 2:31:41I love these retrospectives because it... You know, science is a story.
- 2:31:46It's a human story.
- 2:31:47It transcends generations.
- 2:31:49Yeah.
- 2:31:49We're building on the work, the blood, sweat, and tears of those before us.
- 2:31:56And we are...
- 2:31:57expanding the aperture by which we, again, can just understand so many pieces.
- 2:32:03And people always talk about AI in this, like, oh, in this purely generative LLM chat, GBT universe of, like, oh, these LLMs aren't that great.
- 2:32:13It's just this stochastic parrot that repeats back what it's already heard before.
- 2:32:16No, no, no, no.
- 2:32:17Like, this, like, one of the reasons, like, this.
- 2:32:20It's doing things that we really wanted it to do.
- 2:32:23And it's doing it way better than we could do it.
- 2:32:25Right.
- 2:32:26Or that we necessarily even thought it could do at this stage in its development cycle.
- 2:32:30And I think it's why it's so important to talk about these AI stories in the context of the experimental design, of the historical storyline of these, like, instruments.
- 2:32:42Yeah.
- 2:32:42Right?
- 2:32:42Because at the end of the day, science is so much about instruments.
- 2:32:45Yeah.
- 2:32:46And when we talk about experimental stuff, and this is why we spend hundreds of millions of dollars on this stuff.
- 2:32:52Yeah.
- 2:32:52I just, this was so, so fast.
- 2:32:55We started off first with our CRISPR story, how we understand what CRISPR is, what is Cas9.
- 2:33:02The 2020 Nobel Prize.
- 2:33:03The 2020 Nobel Prize.
- 2:33:05The legal battle between two of our elite research institutions around who owns the human domain aspect of this, and how AI is making that gene editing process better.
- 2:33:17And the same kind of ideas, different implementations, different details, but...
- 2:33:23using AI as a system to augment and make our existing tools more advanced with LIGO for gravitational wave detection.
- 2:33:31And what we're going to be able to see with that is so crazy.
- 2:33:34Yeah.
- 2:33:34And how good it worked.
- 2:33:37And also the timescales of iteration with this AI stuff is much smaller than the hardware timescales.
- 2:33:42And so we have these long arcs of time to get these new hardware instruments online.
- 2:33:48And then we have these much shorter timescales of where we can now use these new AI models to continue to –
- 2:33:55polish the diamond.
- 2:33:58Another great American exceptionalism story with LIGO, too.
- 2:34:01We need to fund our elite research universities and institutions.
- 2:34:04Yeah, and we need to do basic science research because, you know, the technologies that are coming out of LIGO, like these control systems, this is going to be useful in all sorts of technology.
- 2:34:14Right, right, right.
- 2:34:15But, like, it was pushed to its very limit on LIGO, right?
- 2:34:20Because things like LIGO are what...
- 2:34:27make us go all the way to the very end.
- 2:34:29I mean, think about it.
- 2:34:29We're sensing to the quantum limit.
- 2:34:32Yes.
- 2:34:33There's going to be insane amounts of quantum sensing technology that comes out of this.
- 2:34:38Yes.
- 2:34:40Control system technology that comes out of this.
- 2:34:42The mirrors, the vacuum technology that's going to come out of this.
- 2:34:46Yes.
- 2:34:46You know, it's... All of those had to be new fundamentally... New fundamental engineering solutions that have applications well beyond gravitational wave detection.
- 2:34:58Yeah.
- 2:34:58Your new iPhone is going to have...
- 2:35:00You know, these AI-driven optimization models for capturing your 32x zoom.
- 2:35:08Yeah, exactly.
- 2:35:09Selfie.
- 2:35:10It's going to be crazy.
- 2:35:11Unbelievable.
- 2:35:12This is a great lead up to our Nobel Prize week.
- 2:35:15Again, tune in.
- 2:35:16We're going to be doing – there's no channel where you're going to get better coverage of what's happening in this year's Nobel Prizes, understanding the scientists, understanding the history behind their discoveries, how that human story turns.
- 2:35:30What does it mean moving forward?
- 2:35:32I'm so excited to have you on that.
- 2:35:34It's going to be great.
- 2:35:35It's really good.
- 2:35:36Again, we're going to be doing all three days.
- 2:35:37Monday, Tuesday, and Wednesday.
- 2:35:39Monday is when the Medicine Prize comes out, Tuesday the Physics, and Wednesday the Chemistry.
- 2:35:45And Princeton is almost certainly going to be on the podium for one of those, at least we hope.
- 2:35:50At least we hope, yeah.
- 2:35:51At least we hope.
- 2:35:52My name, again, Lester Nare, your host, joined as always by my co-host and our resident PhD, and one of the greatest science communicators of a generation, Krishna Chowdhury.
- 2:36:03Thank you, sir.
- 2:36:04This is from First Principles.
- 2:36:05We'll see you guys for Nobel Prize week.