#403 – Lisa Randall: Dark Matter, Theoretical Physics, and Extinction Events
01:10:18 Share

The following is a conversation with lisa and deal, a theoretical physicist and Cosmologists that harvard for work involves improving our understanding of particle physics, supercedes try berio genesis, Cosmological inflation and dark matter. And now a quick to second mention of sponsor. Check them out in the description is the best way to support this podcast.

We ve got bubble for learning languages, notion for note, taking and team collaboration simply safe for keeping your home safe element for keeping your body feeling good with delicious ness and inside track of forgetting biological data and giving your life advice. Choose wise in my friends. Also, if you want to work with our team where I was hiring at a election, ment that conclusion, hiring or getting touch with me, but gonna treatment of conclusion contact.

And now onto the full that reads, as always, no add in the middle. I try to make this interesting, but if you must skip them friends, please do check out our sponsors. I enjoy their stuff.

Maybe you will too. This show is brought you by bible and APP and website. I used to learn new languages, and you can do have all the languages you need, spanish, for example.

I've been learning a bit of spanish for several reasons, one of which, in case you're curious, this very podcast is getting translated and over doubt regularly in the spanish on spotify. By the brilliant sort fy A I team, you can actually find IT. There's a few episodes now that are fully over of this spanish.

It's really quite incredible. You can also learn a bunch different other languages, turkish, german, italian and french, portuguese. I definitely that because i'd like to travel to brazil soon.

Dis region, indonesian, polish, dutch and russian, which might be useful because I have a bunch of interviews coming up in the russian language where i'll be speaking russian as well. Now those be over dubbed into english. But if you want to hear and understand the original russian, you use bible to catch up and start learning the language.

If you want to understand the C, F, sky in the language was written for some of the poetry like gna mota in the. I said the translations, you will hear thunder member me. I think SHE wanted storms, the rain of the sky with the color of heart crimson in your heart, as IT was then.

will be on fire.

He's one of the great soviet poets in history. I, of course, have trouble finding the right words to translate. I'm long overdue, by the way, on a pocket conversation with the doeskin told to translators that was planned a long time ago.

But IT requires quite a bit of travel, quite a bit of preparation of my side to read several of the C. S. Canovas in both russian english, come up, put great questions that address some of the entry complexities involving the translation that really, really requires a lot of preparation.

But IT also reveals the power of language. Anyway, get fifty five percent off your bible subscription. A bible that come last, legs, pod built, B, A, B, B, E, L that come such like pod, rules and restrictions apply. This shows also about you buy notion first, a no taking up, but also a team collaboration tool, both all the ool people use up for not taking, and all the cool teams use IT for collaboration. The thing they've had recently and have been continuously velocity ing as a notion ai.

It's the best, I would say, integration of a large language models into the no taking process, if you like interacting on ChatGPT or like i've got ten a chance to recently with grow, but want to bring the power of that to the notational process, to the collaboration process, then the notion eyes really great. You can ask notional ee to rewrite the thing you've written to summarized the thing to shorten to length in the you all kinds of stuff. Q I, I like IT because IT gets me going on.

An idea like a IT, generates text as i'm taking the notes and kind of gets through the natural process of a rider block. IT just gets your brain going and all ideas flowing in. Sometimes just having stuff in the page is a really, really huge child.

You can, of course, translate. You can also change the tone and the voice of the thing you ve written. Like you can make yourself more confident, more clear, more friendly or that kind of stuff. There's a million other things.

But really the point here is that it's really nicely integrated into the whole note taking process, which is really the crucial part, not just the power of the large language models, is how well integrated into the tool they use for no taking notion. I can now give you instant answers to your questions using information from across your wiki projects, dogs and meeting notes. Try notion A I for free.

When you got a notion that comes flash legs. That's all over case notion doctors that likes to try the power of notion A I today. This shows also body by simply safe, a home security company designed to be simple and effective.

They have something called the fast protect monitoring, which allows sympathy, modern agents, the sea speak to entertain intruders, to the smart alarm indoor camera. For me, it's a one of the many layers of security, physical, cyber, emotional, all of IT that take very seriously. This one of particular is super easy to set up, super easy to customize, and IT just works and everything is being monitored.

You know, have to worry about anything. And like I said, there's not monitoring agents. They can not speak to the intruder, which is kind of epic.

This world is full of dangers. Sadly, he has to do the basic low hanging fruit steps to keep you up protected. I highly recommend IT just works. The solutions in your life should be simple and resilient and also expensive. So simply save is perfect. Anyway, go to a simply save that conflation h legs to get fifty percent off any simply safe system when you sign up for fast protect monitoring that simply save that cos slash legs. This episode is also about to buy element electronic drink mix.

The thing that I am currently drinking and I drink many, many times a day, IT brings me happiness and enjoy IT prevents me for having any kind of headaches or issues associated with fast thing for twenty four hours, forty eight hours eating only meat, which I do often. You have to make sure that your electoral lights are right. Sodium pattani um magnesium element has an imperfect proportions and is delicious.

My favorite flavor is watermelon salt. They've recently sent me different flavors of chocolate. I don't know that they've always had this or just you've recently sent me several flavors of chocolate.

I think it's chocolate, cy chocolate, a respire chocolate. I also think its a limited time thing, i'm guessing for the holidays. I don't watch holidays, who knows? But you make IT hot and is delicious hot.

I like blue, my mind basically like hat coco. That's what IT a tastes like. And once again, you get all the elections. I was skeptical at first on the chocolate and the hot chocolate, but IT turned out to be incredible.

Anyway, I still probably go to one on once most of time, but sometimes that I, but sometimes in a chilly taxes evening. And by that, I mean, wanted get into fifty decrees. I'll make myself a chocolate try element drink.

I'll make myself a chocolate try element drink. Think about all the beautiful things i'm grateful for in this world. Anyway, get a sample pack for free with any purchase. Tried to drink all my dock flash likes the shows.

Also brought buy inside tracker, a service I used to track biological data from my body that take that data from the blood DNA data, instructed all that kind of self in makes diet and my style recommendations. Just imagine we're all this is headed with a very rapid a development of large language models. Or you can integrate all the scientific knowledge from the various papers that are being actually published, thousands of papers published every month, integrating all of that together with the data that comes from your body and making recommendation.

That's what happened. And insight track was taking the early steps on that. As far as I know, they're not integrating large language models yet, but this seems obvious to me that this is where there's going to be a lot of benefit, at least in the step of the having a conversation about the interpretation of the data in as far as that applies to what kind of die and lifestyle decisions you need to make.

I suppose one way to think about alarms, as you can have a natural language conversation with data as long that day is collected in process properly. I mean, this is just a fascinate future. So i'm a big supportive in SAT track of pushing that future forward.

Get special savings for a limited time when you go to inside track d out cosla ash legs. This is elected freeman podcast to support that. We check out our sponsors in the description. And now, dear friends, is lisa and down.

One of the things you work on and write about his dark matter, we can't see IT, but there's a lot of IT in the universe ah you also end one of your books with the beetles song quote, got to be good looking cause you so hard to see what is dark matter. How should we think about IT? Given that we can see IT? How should we visualized IT in our minds eye?

I think one of the really important things that physics teaches you is just our limitations, but also our abilities. So the fact that we can deduce the existence of something that we don't directly see is really attribute to people that we can do that, but is also something that tells you you can't overly rely on your direct senses. If you just relied on just what you see directly, you would miss so much of what's happening in the world.

And we can generalize this, but would just for now to focus on dark matter. It's something we know is there, and it's not just one way we know is there. In my book, dark matter in the dinosaurs, I talk about the many different ways, eight or nine, that we, we deduce not just the existence of dark matter, but how much, how much is there.

And they all agree. Now, how do we know it's there because of its gravitational force? And individually, a particle doesn't have such a big gravitation force.

In fact, gravity is an extremely weak force compared to other forces we know about in nature. But there's a lot of dark matter out there. IT Carries a lot of energy, five times the amount of energy as the matter.

We know that in Adams is that um so you can ask, how should we think about IT? Well, it's just another form, a matter that doesn't interact with light, or at least as far as we know. So IT interact gravitationally IT clumps IT form galaxies. But IT doesn't interact with light, which means we just don't see IT in most our detection before gravitation wave detectives. We only saw things because of their interactions with light and some sense.

So the IT behaves just like any other matter. Just IT doesn't interact .

light when we say in interact just like other for matter of careful um because gravitation in interact like other forms of matter. But IT doesn't experience electrum actis which is why IT has a different distribution. So in our galaxy it's roughly spiracle a unless IT has its own interactions as another story.

But we we know that it's roughly spiracle um where is ordinary matter can rade IT and climbs into a desk and that's why we seen the milky way desk. So on large scales, in some sense, yes, all the matter is similar in some sense. In fact, dark matter isn't some sense more important because I can collapse more readily than ordinary matter because ordinary matter has has radiated forces which makes IT heart collapse on small skills.

So actually it's dark matter. Serve drives um galaxy formation and then or no matter kind of comes long with that. Um and there's also just more of IT because it's more of IT IT can start collapsing sooner. That is to say the energy density in dark matter dominate over radiation earlier than you would if you just had ordinary matter.

Part of the story of the origin of the galaxy, part of the story the end of the galaxy, and part of the story of the very interaction.

Actually, I mean, in my book I make kind of sort of jokes about, you know, it's like when we think about the building, we think about the architect, we think about know the high level, what we forget about all the workers that did all the grant mark. And in fact, dark matter was really important in the formation, very universe. Then we forget .

that sometimes that's a metaphor on top of a metaphor. Okay, the the unheard voices that do the actual work, okay, exactly.

But IT is a metaphor, but IT also capture something because in fact is we don't directly see IT. So we forget IT it's there or we don't understand it's there. We think it's not. The fact that we don't see IT makes IT no less legitimate. IT just means that we have chAllenges in order to find .

out exactly what IT is yeah but the things we cannot see that nevertheless have a gravitation interaction with the things we can see at the same level is just mind blowing. You know.

IT is isn't because I think what is teaching us is that we're human. The universe is what IT is, and we're trying to interact with that universe and discover what is we've discovered amazing things. In fact, I would say it's more surprising that that the matter that we know about is constitutes a bigger fraction of the universe as IT does.

I mean, we're eliminate, or human. And the fact that we see five percent of the energy dense of the universe, about one, six of the energy density and matter, that's kind remarkable. I mean, why should that be? There could be anything, anything could be out there yet the universe that we see is the significant .

fraction yeah but a lot of our intuition, I think, operis using visualizations and .

the absolutely true and it's certainly write in books. I realized also how many of our words are based on how we see the world um and that's true and that's actually one of the fantastic things about physics is that he teaches you had to go beyond your media intuition to develop intuition that apply at different distances, different skills, different ways of thinking about things yeah.

how do you enter a more fies dark matter?

Hi, I just did. I think I made IT the grant work workers.

oh yeah, that's good. That's why you get paid the big books with the and write the great books okay. So um you also right in a book about a dark matter matter having to do something with the extinction events, the extinction of the dinosaurs, which is kind of a fascinating presentation of how everything is connected. So I guess the disturbances from the dark matter, they create gravity disturbances in the or cloud at the edge. Eva, so system and that increases the rate of asteroid hitting earth.

So I want to be really clear, this was a speculative theory.

I mean, and I .

like to too, and and we still don't know for sure, but we can what we like about IT, so they may take a step back. So we usually assume that dark matter is we being physicists that's just one thing.

It's this basically non interacting in on aside from gravity or very weekly interacting matter um but again, we have to get outside the mindset of just humans and ask what else could be there and so will we suggested is that there is a fraction of dark matter, not all the dark matter, but some of the dark matter. Maybe IT has interactions of its own, just the same way in in our universe. We have lots of different types of matter.

We have nuclear, we have electrons, we have forces, um we have lots. It's it's not a simple model, the standard model, but does have some basic screens. So maybe dark matter also has some interesting structure to IT, so maybe there's some small fraction.

And the interesting thing is that if some of the dark matter does read IT, and you know, I like to call IT dark light, because it's light that we don't see, but dark matter would see IT could radiate that. And then I could perhaps collapse into a disk the same way ordinary matter collapsed mix into the milky way desk. So it's not all the dark matter is a fraction, but IT could considerably be a very thin disco dark matter, thin dense disco ark matter.

And so then the question is, do they exist? And people have done studies now to think about whether they can find them. IT is an interesting target is something you can measure by measuring the positions in velocities of stars, you can find out what the structure of the of the milk way is.

Um but the fun proposal was that the solar system orbits around the galaxy and as he does so, IT goes a little bit up and down, kind of like horses on a carouse. And the suggestion was every time he goes through, you haven't enhanced probability that you would dislodge something from the edge of the solar system in somebody called the word cloud. So the idea was that at those times you are more likely to have this catechism m events, such as the amazing one that actually caused the last extinction that we know are for sure.

I wasn't so amazing for the dinosaurs.

for two thirds of the species on the planet.

yeah. But as IT is amazing for humans.

who and what really is amazing? I mean, I do. I mean, I talk about this in dark. The time is just amazing scientific story, because he really is one of the real stories that combined together different fields of science.

Geologist at the time, or you know, people thought that things happen slowly, and this would be a category mm event. And also, I have to say, you know, if you if you think about IT, IT sounds like a story, like a five year old would make up. Maybe the giant source were killed by some big rocks that came in the earth, but then there really was a scientific story behind IT. And that's also a way like the director, because there's a scientific story behind. So as far, fish ism, my zone, you could actually go and look for the experimental consequences, for the observational consequences to test whether it's true.

I wish you could know, like high resolution details of what that astro came from, like, wear in the word cloud. Why IT happened is that, in fact, because the dark matter, sick, the full, tracing back to the origin, the universe, humans seem to be somewhat special. But I just IT seem like so many facing events at all scales, all skills physics had to happen for.

So i'm really, really glad you mention that, because actually that was one of the main points of my book, dark matter, in the time source. One of the reasons I wrote IT was because I really think we are abusing the planet, were changed the planet way too quickly. And just like anything else, when you alter things, it's good to think about the history of what I took to get here.

And and as you point out, IT took many Operations on many different scales. You know, we had to have the formation of a structure of the formation of galaxies, the formation of the solar system, the formation of our planet, the formation humans. I mean, so many steps that go into this, in humans, in some part, were the result of the fact that this vega object, had the earth made, the dinosaurs go extinct, in mammals developed. I mean, IT is an incredible story. And yes, something else might come of IT, but IT won't be us if we mess .

without too much. But IT is on a grand scale. Earth is a pretty ilian system.

Can you just clarify this? Fascinating, the shape of things. So the shape of the milk ways of the observable stuff is mostly flat. And he said, dark matter tends to be spiral, but a subset of that might be a flat disk.

So you want to hear about .

the shape of things? yes.

So structure formed early on. And now our structure that we live in is so we know about the milky wake alex y so the milky wake alaya has the this you can see in a dry dark place that's where starts and light is but you can also measure in some ways the dark matter and we believe that dark matter is more or less vertically distributed.

Um and like we said, there's a lot of IT not necessary in the desk, but just because it's a fear, there's a lot of IT sitting there in the reason IT doesn't collapse, as far as we know, is that IT doesn't really can't radiate the same way. So because I can radiate or narrative collapses in the sexually because of conservation, one of the momentum IT because IT stays the desk and IT doesn't just collapse to the center. So our suggestion was that maybe there are some components of dark matter that also radiate.

Like I said, that's far from proven. People have looked for this. They see some evidence of some days of certain densities. But these are all questions that are worth asking. Basically, if we can figure IT out from existing measurements.

why not try? okay. So there's not all dark matters made the same.

Well, that's a possibility. We actually don't know dark materials in the first place. We don't know most of IT is we don't know if fractionalized mean it's hard to measure.

Why is IT hard to measure for exactly the reason you said earlier? We don't see IT. So we want to think of possibilities for what I can be if especially if those give rise to some of observation consequences. I mean, it's it's a tough game because it's not something that's just they are further taking. You have to think about what could be and how you might find up.

and where you detect its gravitation effects and things we can see.

That would be the way you detect the type of dark matter i've been talking about. People have suggestions for other forms of dark matter. They could be particles called axons.

They could be other types of particles and then there are different ways of detecting at me the most popular candidate for dark matter probably until pretty recently because haven't found IT is something called wimps weekly interacting master particles particles that have massed about the same as the higgs pose on mass um and turns out then you will get a about the right density of dark matter. But then people really like that, of course, because IT is connected to the standard model, the particles that we know that. And if it's connected to that, we have a Better chance of actually seeing IT. Fortunately, unfortunately, it's also a Better chance you can rule IT out because you can look for IT. And so far now when is found IT.

we're still look at for IT. Is that one of the hopes of the large hydron .

collider that was originally one of the hops of large hadron collider? I said at this point, I would be very unlikely, given what they already accomplished. But there are these underground detectors seen on detectors that look for dark matter coming in. And they they are going to try to achieve A A much stronger bound that exist today.

Just take the attention. Looking back now, what's the biggest do you insist uh, to humanity that the L. H. C. Has been able to provide?

It's interesting. It's both a major Victory. The hix posson was proposed fifty years ago, and IT was discovered.

The hicks mechanism seem to be the only way to explain on ETC particle masses. And IT was right. So in the one hand, IT was a major Victory. On the other hand, i've been in physics long enough to know, was also a cautionary tale in some sense, because at the time I start on physics, we had some proposed something in the united called the superconducting super collider.

A lot of physicists, i'll say, particularly in europe, but I say a lot of physical, we're sing when that the large hadron collider would have the energy reached, necessary to discover what underlies the standard. Mal, we don't want to just discover the standard we want to with the next. And I think here people were more cautious about that.

They want to have a more comprehensive search that could get to higher energies, more events, so that we can, you know, we can really, more definitely to rule that out. But in that case, many people thought anyone would be, there would happen to be a theory called supersonic. So a lot of physical thought I would be a supersonic try.

I mean, it's one of the many factors I think that went into the fact the large pattern collider became the only machine in talent. And um the superconducting super collider would have just been a much if I really had achieved what I was supposed to, would have been a much more robust test of the space. So so I take for her, humanity is both attribute to the ability discovery in the ability of really believing in things that they have the confidence to go look for them. But it's also a cautionary tale you don't want to know, assume things before you've been actually found. So you want to do things in you know you you want to believe in your series, but you also want to question them at the same time in ways that you're more likely to discover the truth.

but is also an illustration of grand engineering effort that humanity can take on and maybe a lesson that you could go you and bigger.

Um i'm really glad you said that there too because that that's absolutely true. I mean, it's IT really is an impressive it's it's impressive in so many ways, impressive technologically, impressive ment engineering level. It's also impressive that so many countries work together um to to do this. IT wasn't just one country and how IT was IT was also impressive that IT was a long term project that people committed to and made IT happen. So IT is a demonstration that when people set their minds to things and they commit to IT, that they can do something amazing.

But also, any states may be a lesson that bureaucracy can slow things down.

You free and and politics, politics and economics, many, many things can make them faster and make them slower.

Society is the way to make progress. Politics is the way to slow that progress down.

Well, I don't want to understand that because without politics, yeah they up either so but .

you need broccoli.

Um but sometimes I do think what I mean, you're not asking this question. But sometimes I do think when I you know think about some of these conflicts, you know sometimes it's just good to have a project that people work on together in. There were some efforts to do that with in science too, to have pastor anian in israeli work together. Project costs me um I think it's not a bad idea when you can do that, when you can get you know sort of forget the politics and just focus on some particular project sometimes that can work some kind .

of forcing functions, some kind of deadline that gets people sitting room together and you're working on a thing. But as part of that, you realize the common humanity that you all have, the same concerns, the same hopes, the same fears, the same that you are all human. And that's an accidental side effect of working together on a thing.

I that substate true, and it's one of the reasons cern was formed. Actually, there was post world war two in love, european physicists had actually left you up, and they want to see european's work together and answers rebuild and, and IT worked. I mean, they, they did. And it's true, and I often think that in one of the major problems is we just don't meet enough people so that everyone thinks seems when they seem like the other, it's more easy to forget their humanity. So I think this is important to have these connections .

given the complexity, all Cosmos ical skills involved here that LED to the extension of dinosaur s. When you look out at the future of earth, do you worry about future extinction events?

I, I do think that we might be in the middle of an extinction right now if you to find IT by the number of species that are getting killed off. And it's a little bit, you know, it's a complex system. The way things respond to events is sometimes things above.

Sometimes animals just move to another place. In the way we've developed, the earth is very hard for species just to move somewhere else. And we're seeing that with people now too. I mean, I know people are worried just about A I taking over, and that's a totally different story. We just don't think about the future very much. We think about we are doing now, and we certainly think enough about all the animals that we're destroying, all the things that are precise to humans that we sort of rely on.

It's interesting to to think whether the the the things that threatened us is the stuff we see this happening gradually or the stuff we don't really see that's onna happen all sudden. And sometimes I think about what is what you would be more worried about, because this seems like like what the asterisk nuclear war IT could be, stuff that just happens one day.

You know, when I say one day mean overspend of a few days or few months, but on, you know, not in the scale of decades and centuries because we sometimes mostly talk about stuff that's happening gradually. But you can be really surprised. It's actually .

really interesting. And that was actually one of the reasons IT took a while to determine what IT was, that IT caused the last extinction because people did think at the time of many people thought that things were more gradual. And the idea of extinction was a very, was actually a novel concept at some point.

I mean, these aren't predictable events necessarily. They're only predict table on a grand scale. Um but sometimes sometimes they are in and I think people were pretty aware that nuclear weapons were dangerous. I'm not sure people are aware now as they were, say, twenty or thirty years ago and that certainly worries me.

Um I have to say was not as worried about A I as other people but no, I interested in and it's not I mean, it's more than as soon as you create things that we lose control over, its scary. And the other thing that we're learning from the events today is that is that IT takes a few bad actors. IT takes everyone to sort of make things work well.

IT takes not that many things to make things go wrong. It's the issue with disease. You know, we could find out what causes a disease, but to make things Better is the story that simple.

Sometimes IT is. But for things to be healthy, a lot of things have to work. For things to go wrong, only one thing has to go wrong.

And so it's amazing that we do in the same is true for a democracy. For democracy to work, a lot of people have to believe in IT. A few bad actors can destroy things sometimes.

So a lot of the things that we really rely on are delicate, equally, brooms with someone you know in. There is some rows in the systems we tried to build in a business, but a few extreme events can sometimes alter things. Um I think that's what people are scared of today in many ways.

They're scared of for democracy. They're scared of IT for peace, are scared of IT for A I I think they're not as scared as they should be about nuclear weapons, to be honest. Um I think that's a more serious danger than people realize.

Um I think people are a little bit more is scared about pandemics and they were before um but I still say they're not super scared about IT. So you're right, there are these major events that can happen, and we are setting things up so that they might happen. And we should be thinking about them.

The question is, who should be thinking about them? How should we be thinking about them? How do you make things happen on a global scale? Because that's really, really what we need.

IT certainly should be a source of division, should be a source of grand collaboration.

Probably would that nice?

yeah. I wonder what to be like. A, to be a dinosaur must have been beautiful to like. Look at that s just enter the atmosphere until, like everything just would I that would be one of the things I will travel back in time too.

You know, that's also one of the things that I think you probably could do with virtual reality. I don't think you have to be there and get. I think there is something you know, it's an event you're just watching, you're not doing anything, you're just looking at IT.

So maybe you could just be created actually heard that there's a nuclear weapon explosion experience in virtually reality that's good to mind you about. Like what I would feel.

I have to say, you know, I saw, I got, I got award from the museum of nuclear history and technology in the southwest. And I went to visit the museum, which turned out to be mostly a museum of nuclear weapons. And the scary thing is that they look really cool.

You know, it's true that you have that, yes, this is scary, but you also have this. This is cool feeling. And I think we have to get around that because if I kind of think that, yes, you can be in map, I am not sure that's going to make people scared. Has have they actually asked afterwards.

are you more or less here? It's a good it's it's a really good point. I mean, that's a good summer of just humanity in general were attracted to creating cool stuff. Even those can be dangerous. And actually.

that was the really interesting thing about serving the museum. And actually I IT was very nice because I A tour from people who have been working there in the cold, warm, actually, one, two people from in, and a project that was a very cold tour. And you just realize just how just the thing itself gets you so excited.

I think that something that sometimes these movie is missed, just the thing itself. You're not thinking about the the overall consequences. And IT was kind of like in some ways, IT was like the early silicon valley.

And people were just thinking, like, what if we did this? What if we did that? And you know, not take keeping track of like what the fur feral consequences are. And you've definitely see that happening with A I now, I mean, I think that was the moral of the battle that just happened that you know, it's just full speed ahead.

which gives me a really great transition. Another quote in your book, so you you write about the experience of facing the supply me in physics and you quote rya rok. Quote for beauty is nothing but the beginning of terror, which we are still just able to endure. And we're so odd because it's mainly distained to analia. It's pretty intense if I think applies to nuclear weapons.

But he also, I mean, at a more monday perhaps level, I think IT applied is really interesting. One of the things I found whenever at these books is some people love certainty. Scientists kind of many revel in uncertainty.

It's not that you want to be answered and you want to solve IT, but you're at this edges where is really frustrating. You don't really want to not know the answer, but of course, if you you knew the answer, that would be, that would be done. So you're always at this edge where those you are trying to sort things out and there is something scare.

You don't know why. You don't know if there's gonna be a solution. You don't know if you're going to find IT. So it's not something that can destroy. There is, is just something that you do on your an individual level. But then, of course, there are much bigger things like the ones you are talking about where they could actually be dangerous. This stuff I do I just want to be clear i'm doing therefore al physics not very dangerous um but sometimes things end up .

having their consequences than you think yeah but dangerous in a very pragmatic sense but isn't IT still in part terrifying when you think of a just the size of things like the size of dark matter, the power of this thing in terms of um is potential gravitation effects, just Cosmological objects of a black hole, the center of our galaxy?

So this might be where why i'm if this isn't, why different from other people, because i'm not such a big fan of humanity in some ways, some ways I am. But the idea that we were everything would be really boring to me. I love the idea that there's so much more out there that there's a bigger universe and there's lots to discover, that we're not all there is want to be disapointment. We were all .

there is yeah. And the full diversity of other stuff, it's prety .

interesting. You we have no idea how matters. We we know what what we can observe so far. So the idea that is other stuff out there that will yet have to figure out, it's exciting.

Let me ask you out there question. okay. So if you think of the humans on our life, on our as this pocket of complexity that emerged.

you know that .

in the pressure conditions that came to be in dani an evolution, however, life originated getting as possible. There are some pockets of complexity that sort inside dark matter OK.

So that's possible. I I chemistry, biology evolving in .

different ways. And that's one .

of the reasons we suggest. I mean, it's not the reason, but I would be true if there were the type of interactions we suggest. I mean, I would need more complex ones and we don't know.

Um I will say that the condition sacrifice to life and complexity, there are conflicts. They are unlikely. Um so it's not like there's great ahead that would happen, but there's no reason to know that IT doesn't happen. It's worth investigating. Are there other forces that exist in the dark matter .

sector is is so the dark matter sector doesn't have all the forces the standard model of physics right .

as well as we know he doesn't have any IT might have IT at some low level, but I could have its own forces just like, yeah, the dark matter might not experience our light. Maybe IT has its light that we don't experience.

So there could be other kinds of forces.

I mean, there could be other kinds of forces, even with our sector that are two week for two have discovered so far or that exists in different skills that we know about. I mean, we detect what had interact strongly enough with our detectives to detect.

So it's worth asking, and that's one of the reasons we build big lidar to see are there other forces, other particles that exists, say, at high rent is a shorter distant scales than we've exported so far. So it's not just in the dark matter sector. Even in our sector, there could be a whole bunch of stuff .

we don't yet know. So maybe let's zoo look at the standard model, particle physics. How does dark matter fit into first short, what is IT? Can you explain what the standard model is?

So the tender model of particle physics is basically tells us about natures most basic elements and their interactions. And so it's the substructure as far as we understand that. So if you look at items we know, they have nuclear eye in electrons.

Nuclear, I have put toons in nutrient in them. Problems in new trans have particles called corks that are held together by something called the strong force. They interact through the strong force, the strong nuclear force, and some may called the weak nuclear force and electric megacity m.

So basically, all those particles and their interactions described many, many things. We understand that the standard model we now know about the hicks goes on, which is associated with how elementary particles get their mass. So that place of the puzzle has also been completed.

We also know that there are kind of a weird ray of masses of eliminate particles. There's not just the up and downtown ark, but there are heavy aversions of the up and downward k charm and strange top and bottom. There's not just the electron.

There's a moon in a town. There are particles colony tinos, which are under intense study now, which are partner whist leptons through the weak interactions. So we really do know these basic elements, and we know the forces.

We know. I mean, what we're doing, particle physical experiments. We can usually even ignore gravity cept in exceptional cases that we can talk about.

So those are the basic elements in their interactions. Dark matter stands outside that it's not interacting through those forces. So when we look at the world around us, we don't usually see the effects of dark matter.

It's because there's so much of IT that we do and IT doesn't have those forces that we know about. But the standards has worked spectacularly. Ly, while I testing to a high degree precision, people are still testing up.

And one of the things we do is physicist is we actually wanted to break down at some of we're looking for the precision measurement or the energy or whatever IT will take where those where the animal is no longer working like. Not that it's not working approximately, but we're looking for the deviations. And those deviations are critical because they can tell us what underlies the standard model, which is what we really want to see next.

Working, you find the places where the stand model brings down like what what are the place you can see those tiny deviations.

So we don't know yeah, but we know the kinds of things you would not want to look for. So one obvious place to look is that higher energy, and we're looking at the large hadron collider, but we'd love to go beyond that. High energies means shorter distances and IT means things that we just couldn't produce before, I mean, equal empty.

So you have a happy particle. You don't have enough anh to make IT. You'll never see that.

So that's one place. The other places. Precision measurements, if you understand, the mall has been tested exquisitely. So if if it's been tested one percent, you want to look at a tenth of a present. And there are some processes that we know shouldn't even happen at all in this animal or happen at very press level, and those are other things that we look for. So all of those things could indicate this something beyond what we know about, which, of course, will be very exciting .

when you just step back and look at the standard model, the corks and all the different particles. And trios isn't a while. How this system came, came to being quotes is underpins everything we see.

absolutely. And that's why we'd like to understand IT Better. We want to know is that part of some bigger sector, why are these particles? Why do they have the masses? They do yeah um why is the exposed and so like compared to the mass could have had, which we might be even expected based on the principles of special relativity in quana .

mechanics. So that's a really big question. Why are they what they are changes.

That's one of the things we're trying to study. Why is that what that is?

I mean, even just like the mechanical creates stuff like the way a human being is created from a single cell and genesis like this is the whole thing like, but you build up this thing, all of the this whole thing comes to be from just like forget .

that is interacting with the environment.

sure. Okay, right, right? It's not instant, right? Well, that's a really good question. Is how much of is the environment? Is just the environment acting on a set of constraints? Like how much of a is just the information in DNA or the information? How much is in the initial conditions of the universe, a versus the the some other thing acting IT these .

are big questions. These are big questions and pretty much every field um you know we for the universe we do consider IT, you know it's everything there is by definition but people now think about is one of many universes um and of course it's misnomer, but could there be other places where there are self contained gravitating systems that we don't even interact with? So but those are really important questions. And the only way we're going to answer to them as we go back as soon as we can, we try to think theoretically, and we try to think about observational consequences.

So all we can do. One interesting way to explore the standard models, to look at your fun nuances. Disagreement with carlo reveley, when you talked about him writing in his book electron donor, was that they exist when they interact.

They materialized in a place when they collide with something else. And you wrote that just be the whole thing because it's kind of interesting. Stocks may not achieve a precise value until they are traded, but that doesn't mean we can't approximate their worth until they change hands.

Similarly, electronic might not have definite properties, but they do exist. It's true that the electron doesn't exist as a classical object with definitely position until the position is measured. But something was there which physicists use a way function to describe.

It's a fascinating wisse disagreement. So do electrons always exist or not? Does a tree fall in the forest, if not there?

So i'd like to think of the universe is being out there, whether and I I mean, IT would be really weird if the only time things came into existence was when I saw them or I measured them. And I mean, I could believe that the middle doesn't exist because i'm not there now. I mean, that would be kind of ridiculous.

I think we would all agree on that. So I think there's only so much that we can attribute to our own powers of seeing. So and the whole system doesn't come into being because i'm measuring IT.

And so what is weird? And this isn't anything to scree me about the standard, this and how you interpret mechanics. I mean, I would say that those way functions are real.

I mean, one of the things that to forget that particle physics does that quin filter says is that electrons can be created and destroyed is is not that every electronic has to be a new world saying that can be that's what happens that collider is particles get created and and destroyed um but that doesn't mean that I have electron in an adam. It's not there. It's early there. We know about its its charges there.

So physics is a kind of way to see the world. So what at the bottom? What's the bottom turtle? What give a sense that there's a bottom reality that we're trying to approximate with physics?

I think we always have in our head maybe that we'd like to find that, but I have to I mean, I might not seem so, but I think i'm kind of more humble than a lot of is this. I'm not sure that we're we're onna get to that bottom level, but I do think we're going to keep penetrating different layers and get further.

I just wonder how far away we are. You know we all wonder .

that um and something like what's even the measure of how far away we are. I mean, one way you can measure IT is just by our everyday lives. In terms of our everyday lives, we've measured everything in terms of what underlies IT.

There's a lot more to cy, and so part of IT has to do how far we think we can go. I mean, that might be that the nature of reality changes so much that even these terms are different. Maybe both measure. No, the notion of distance self might breakdown at some point.

But also to push back on that, we've measured everything. Maybe there is stuff we haven't even considered is measurable, for example, consciousness or that there there might be stuff, just like you said, forces on and detective.

So it's an interesting thing. So what and this is often a confusion that happens. So the sort of the fundamental stuff underlying IT, and then there's sort of the higher levels, but you know what will call like an effective theory at some level, you know?

So we're not always working. I mean, when I throw a ball, I don't tell you we're every adamites, I tell you there's a ball. And so there might be different layers of reality that are built to on terms, on terms of the matter that we know about, terms the stuff we know about that.

And when I say we've measured everything, I say that with a great of soul. I mean, I measure me everything understand about so. So there's lots of phenomena that we don't understand that we but often there are complex phenomenon that will be given in terms of the fundamental ingredient that we know about.

But that is an interesting question because, yes, there's phenomena that are at the higher level of abstractions that emerged. But maybe I could consciousness. There is far out people that you know think that consciousness is pi.

Guess right? That is, that is there is going to be almost like a fundamental force of physics. That's consciousness.

That premier is not mean using a crazy sorry, okay, when you have a far out theory, yes, the thing you do is you test all the possibilities within the construct that exist, so you don't just jump to the most for a possible. I think you can do that. But then to see if it's true, you either have to find evidence of IT or you have to show that it's not possible without that. They were very far from that.

I think one of the criticisms of your theory, an dinosaurs, was that IT requires, if I remember correctly, for dark matter to be weirder than that already is is. And then I think you had a clever response .

that I am not at them, but I think we've no idea how we are dark. It's based on everyone thinking they know what dark matter is. I mean, so where they already is, I mean, it's not already anything. We don't know what IT is. So is no Normalization here.

So dark matter do we know that if dark matter very is intensity.

IT definitely does an interest just like, I mean, so for example, there's more dark matter in galaxies there. There's between, alex. So we eat a climbs. I mean, so it's it's matter, so it's distributed like matter .

IT is matter. IT does clump. But the the full details of how clumps and again, of the clumping.

it's understood of pretty well. People do simulations mean where where people are are always looking for things, including us as particle, that is, sort of a small scales are the deviations of small scales today indicating other interactions or other processes or interactions with barriers, that is to say, Normal matter that we don't understand. But in large scales, we have a pretty good understanding of dark matter distribution.

You were part of a recent debate on quote and science and cover reality. Let me ask you this question then, what do you think is the limits of science?

I'm smart enough to know. I have no idea. And also, it's not clear what science means, right? Because there's a signs that we do which is particle physics. We try to find fundamental things and figure out what their effects are this science psychology gy, where you know it's added a higher level.

The kind of questions you ask different, the kind of measurements were different um the kind of science is going to happen in the third mechanical age min or even A I or like what does that mean to answer a question, does that mean that we can predicted? Does that mean that we can reproduce IT? So I think we're coming up against serve the definition of what we mean by science as human beings.

So in terms of the science that we can do, I don't think we will know. And until we get there, um you know we're trying to solve hard problems and you know we've made progress. I mean, if you think of how much science has advanced in the last century or century and a half, incredible.

I mean, you know, we didn't even know the universe was expanding at the beginning of the twin th century. We didn't know about quana at the begin of the that's a lot in a relatively short time depending on how you think of time. Um so I think he would be premature to say we know limitations and a various .

post without the history which I was sold everything or declared or at least various people .

with various people exactly .

declare that were solved everything. So this also a good place. Uh maybe could you describe the difference in top down and bottom up approaches to theoretical physics that you talked to on the book?

So you could try to jump in and say, I have a theory that I think is so perfect um that I can predict everything from IT or at least predict some salient features from IT.

Let's up that .

would be top down by them. Up is more like, you don't know, like the questions we just ask, why are masses what they are? We measure things. We want to put them together.

And usually a good approaches to combine the two, if you ask a very specific question, but combine that with the methods of knowing that there could be a fundamental, the underlying, sometimes you make progress. I mean some you know, the community tends to get segmented or fragmented into people who do one of the other. But there are definitely times, I mean, some my best collaborations with with with people who were more top down than I am.

So they we come up with interesting ideas that we want to thought of this. Either one of us. So work individually.

We just say the truly big leaps happen top down. Like I sign.

Einstein was not a top dog person in the beginning. He was special. Relativity was very much in thinking about, they were thought experiments, but he was very much.

The original theory about relativity is something like on the nature of elector magical ism. He was trying to understand how maxon's laws could make sense when they were, you know, seem to have different cemeteries that we have thought they were. So he was very much a bound of a person. In fact, he resisted top down for a long time.

Then when he tried to do the theory of general relativity, general theory relativity, which would you want to call um incorporating gravity into the system where you need some feedback, then he was held by a mathematician who were developed some differential geometry and helped him figure out how to right down that. And after that he thought top down was the way to go. But he actually didn't make them much progress, but certain. So I think it's you know now you have to think IT was just one of the other. In fact, a lot of people made real progress, were rooted in actual measurements.

well speaking mathematicians, uh, what to use the difference because you've had a bit of foot in both, uh, between physics and mathematics in the way that helps .

us understand the world. This, to be Frank, there's a lot more overlap, physics and math and has been I mean, well, maybe not more, but there's certainly a lot. But I think again, the kinds of questions you're asking your earth, usually different mathematicians like the structure itself physicists are trying to concentrate on to some extent on the consequences for the world um but there is a lot of over .

the string theory. An example is certain there is where there's a certain kind of mathematical beauty to IT. There's also there's .

also some really cool ideas that you get in particle physics where you can describe what's going on and connected other ideas that's also really beautiful. Um you know I think I think basically insights can be beautiful. You know they might seem simple, but sometimes and sometimes they genuinely are and sometimes they are built on a whole system that you have to understand before. If you actually saw on science equations written out and components, you won't think so beautiful. You write in a compact way.

looks nice. Uh, what do you think about the success is in the failures of string theory? To what degree do you think it's succeeded to? What degrees is not succeeded yet or has failed?

I think to talk about any science in terms of success and failure often missed the point because there's not some absolute thing. And I think I do you think that string tears were a bit overly ambitious, not overly ambitious, but a little bit overly arrogant in the big inning, thinking they could solve many problems that they weren't going to solve.

That's not to say the method s and advances in string theory don't exist and um but they certaine weren't able to immediately solve all the problems I thought that itself but IT has given us tools. IT has given us some insights um but IT becomes almost a sociological question like how much IT should be one of the other. I do think that you can get caught up in the proms themselves and and sometimes you can get caught up in the message and just sort to other examples so the real physics insight often come from people who are thinking about physics as well as as the math.

because you mention A I is there hope that A I may be able to help finds of interesting insights? I mean, another question, another would ask this question is, how special, or humans are able to discover novel insights about the world?

That's a great question. Um and IT depends on what kind of incident going to find that out. I mean, you know it's because it's hard to think about something that doesn't quite exist yet.

I mean, I could just think about something, take a step back. You know, it's look at like china stand three, four dimensions. You go back to three dimension. So to go to something you can imagine. So you can sort of say a lot of the things in a very different level about the internet.

You can say, you know, has the internet help do things and that, you know, he definitely took on a life of its own some sense, but is also something that we were able to tame. You know, I know that I myself want to be able to write books s in the internet access because I went to have the time to go to library and look everything and um I helped me ano mistake. And in some sense A I could be that in very nice world, that could be a tool that helps us go a step further or then we would and lot more efficiently.

And it's already done that to some extent or IT could be like the part of the internet that we can control that warning politics or whatever. So and there's certainly a lot of intimate that can do that. Then there are even bigger things that you know people speculate about about A I to do with some things but in terms of actually figuring things out um you know where in the early stages yeah .

the several directions here. One is on the theory, proper size of world from alphago, where everything is much more precise, and we have large language model type of stuff. One of the limitations of those is that seems to come up with convincing looking things, which we don't know if is sure or not. And that's a big problem .

for physics, not less generations of stuff that we have. So the question is, so they still breakthrough and A I waiting to happen and maybe they are happening and maybe there will be good. Maybe not, but that's not quite the same.

I mean, maybe to some in some cases, it's just patent recognition that these two important things, but sometimes there could be something more insight ful than that that I can even put my finger on so IT forces us to. I mean, we don't really understand how smart we are. We don't understand how we think about things all that well, actually.

But one thing is true that we are lot more efficient right now then computers. And coming up with things, we require a lot less energy to do that. So if computers figure out how to do that, then it's going to be A A totally different ball game.

So and so there are clearly kinds of connections that we don't know how we're making, but we are making them. And so that's going to be interesting. So um you know I said we're in early stages, but this is changing very rapidly. But right now, I don't think that is actually near discovered like new laws of physics, but couldn't in the future.

maybe I can I will raise big questions about what is special about humans that we don't quite appreciate. You know, there could be things that are like that leap of insight that happens, truly novel ideas that could potentially be very difficult to do.

So there are sort of abstract questions like that.

There's also questions of how is IT that we can address to some extent? You know, how will A I be used in the context of the world we live in, which is based on in at least our countries, based on capitalism in a certain political system, and how will global politics deal with the how will our capital system deals that what will be the things that we focus on doing with that? How much will researchers get controller bit um to be able to ask different sources of questions? I mean, you know while I was starting out, people were doing these kind of toy problems. But what will IT actually be applied to and what will be optimized to do this? There is a lot of questions out there that it's really important.

We started dressing what you is the most beautiful and solve problem in physics and Cosmology, which is really exciting for can unlock the mystery of in the next few decades.

And so is IT. What's the most beautiful and self problem, or what is the most beautiful and self problem? I think we can make progress on.

oh boy, we make progress on in the next few centuries.

This most the questions, the big questions, have to do with what underlies things, things healthy. Started with at the base of IT. This also just basic questions like like the U S earlier half far.

Will science take us? How much can we understand um their questions like how we got here um what I realized that are there you know but also I mean is really deep questions like you know what fraction are we actually seeing or if there are these other forces if there is another way of seeing the world are there gala universes beyond their own that there so totally different? How do we even comprehend them?

I mean, how do we detect like what would we even think about them? So there's a lot about trying to get beyond. It's always just getting beyond.

I are limited vision and limited experience and trying to see what I delighted both at small skills and at large skills. We just don't know the answers. I mean, i'd like to think that we understand more about dark matter, about dark energy, about are there extra dimensions, things that we actually work. But it's play a lot beyond what we work on this yet to be discovered.

The understanding the exact dimensions piece would be really interesting totally.

I mean, if IT is a health universe, went from higher dimension to what we see, or do you know, are the extreme mentions present everywhere? I mean, you know, one of the really interesting piece of physics, we did that talk about my facebook wall procedures, finding out that there can be a higher dimension, but only locally. Do think this is the gravity of a lower dimension.

So IT could be like only locally do we think we live in three dimensions that could be hired. Dimensions is different. This not actually the gravity we have, but.

IT, there's all sorts of phenomenon that might be out there that we don't know about, all sorts of evolution things, time depends that we don't know about. And of course, that's from the point of view of particle physics, from the point of you other kinds of physics we're just beginning. So who knows?

You have to. Physics changes throughout. This is now commotion, ious throughout the universe sets. I'll be weird. I mean.

you know, for the observer, able universe is the same. But beyond the observer able universe is.

what advice would you give?

You've had an.

except for a career, what advice would you give to Young people, maybe high scope college, and how to have a career they can be proud of and our life they can be proud of?

I think the weird thing about being a scientist or an academic, and you have to believe really strongly what you do while questioning at all the time, you can you know, and that's that's a hard baLance to have sometimes that helps to collaborate with people. But to really believe that you could have good ideas at the same time, knowing they could all be wrong, that's it's a tough type up to walk sometimes but to really um test them out.

Um the other thing is sometimes you know if you get too far buried, do you look at and think out this so much out there and sometimes it's just good to bring you back home and just think, okay, can I have a as good ideas the person next to me rather than, you know, the greatest physicists who ever were lived? But right now, like you said, I think there's lots of big issues out there and is and it's hard to be on set and sometimes it's hard to forget the role of a physical. But I think, you know, Wilson said that really well.

He said, you know, when they were building premier lab, IT was like, this wont defend the country, but it'll make IT worth defending. You know, this just the idea that, you know, in all this, K. S, it's still important that we still make progress in these things. And sometimes, you know, when major world events are happening, it's easy to forget that. And I think those are important to you don't want to forget those, but to try to keep that baLance because we don't want to lose what IT is that makes human special?

That's the big picture. Do you also lose yourself in a simple joy of puzzle solving?

Yeah, yeah. I mean, I that we all like solving puzzles. And actually one of the things that drives me in my research is IT inconsistencies when things don't make sense, that really bugs me. And I just will go in to, you know, different directions to see how could these things fit together so bugs you.

but that motivates you. Yeah, toit, until doesn't. Because I think I .

have this underline belief that IT should make sense. You know, the world comes at you in many ways and tells you nothing should make sense. But if you believe that that makes sense, that you look for underlying logic, and I think that's just good advice for everything to try to find.

Like why does this do this? I think, you know, we talk I talk about a factor theory in my second book now and have a store a lot. You know, it's sort of rather than asked the big sometimes we just ask the questions about the immediate things that we can measure.

And we can, like I said, we can sometimes tell me that will fail, but we can have these effective theories. And sometimes, I think, you know, when we have promised big questions, it's good to do for effective theory point. You know, why do I find this as why and why is the world we have the way that we think things are beautiful that we live in?

I mean, you know, i'm not sure if we had different senses or different ways of looking things. We were nearly find a beautiful. But I have to say IT or IT is kind of fantastic. That number, how many times I see a sunset, I will always find a beautiful. It's like I don't think ever see the sense that whatever you know, it's just always beautifully you always know and so there's there are things that is humans you know clearly resonate with us but you know we were maybe of all that way that's about us um but in terms of figure out the universe, it's kind of amazing how far we've gone in know we have discovered many, many wonderful things um but there's a lot more out there and I hope I hope you have the opportunity to .

keep going and with effective theories, one small step at a time to keep unravel .

in the also having in mind the big questions are looking .

out to the stars he said, the sunset for me, it's the sunset, the sunrise and just looking at the stars and wondering what's all out there and having a lot of hope that humans will figure that out.

right? I like IT .

they said, well, thank you for being one of the humans in the world for that are pushing IT forward and singing out this beautiful puzzle of hours. And thank you for talking today. amazing.

Thank you.

Thanks for listen to the conversation release randell. To support this pot guests, please check out our sponsors in the description. And now let me leave you some words from Albert einstein.

The important thing is to not stop questioning. Curiosity has its own reason for existence. Thank you for listening and hope to see you next time.