Into the Impossible With Brian Keating - The Second Kind of Impossible (#020)

Episode Date: January 8, 2019

THE SECOND KIND OF IMPOSSIBLE: The Extraordinary Quest for a New Form of Matter is the exciting, first-hand story of how Paul Steinhardt, the award-winning physicist and Albert Einstein Professor in Science at Princeton University, predicted a new type of matter – the quasicrystal – shattering centuries-old laws of physics. Steinhardt’s quest to prove the natural existence of quasicrystals takes him on a globe-hopping scientific journey from Princeton to Italy to the remote mountains of Russia’s Kamchatka Peninsula. In a “suspenseful true-life thriller of science investigation and discovery” (Publishers Weekly), readers are taken along for the ride as Steinhardt challenges commonly held assumptions about settled science, refuting skeptics and disproving their notions of impossibility along the way. Steinhardt’s search to prove the existence of this rare crystal structure began in the early 1980s, when he first proposed the existence of “quasicrystals.” While studying abstract tile patterns, Steinhardt and his graduate student discovered a scientific loophole in one of the most well-established laws of science and, exploiting that, realized it was possible to create new forms of matter. In this podcast, co-associate director of the Arthur C. Clarke Center for Human Imagination, Professor Brian Keating, and Professor Paul Steinhardt explore a wide range of ideas from the discovery of new forms of matter to string theory and the sociology of science. Enjoy! Learn more about your ad choices. Visit megaphone.fm/adchoices

The only thing we can be sure of about the future is that it will be absolutely fantastic. Five, four, three, two. Welcome, everybody, to the first episode of Into the Impossible from the Arthur C. Clark Center for Human Imagination at the University of California, San Diego. Remind you that Into the Impossible, rather, is a unique podcast that really aims to explore the boundaries of human imagination and curiosity. in every endeavor from the arts to the sciences to technology and beyond. And we've done episodes with numerous luminaries and intellectuals, from Nobel Prize-winning physicist to Pulitzer Prize-winning poets, to astronauts, to everyday thinkers and intellectuals around the world.

So it's a great honor and pleasure today to start off the new year, 2019, with a podcast with an episode of one. of my scientific heroes and mentors, Professor Paul Steinhart, who is the Einstein Professor of Natural Sciences at Princeton University. He's also the author of two books for popular science audiences. And today we're going to be talking about his latest book, which is called The Second Kind of Impossible, which is due to come out tomorrow, January 8th. So this is book launch Eve, a very, you know, nervous time in any author's life, quite similar to waiting the birth of a child or Christmas morning, which for Paul was the birth of himself and also Christmas

Day. Paul's birthday is on Christmas Day, shared with a famous, a person who achieved a great deal of fame throughout humanity, which is, of course, Isaac Newton. And that is one of the many similarities between Paul and the great physicist. Today we're going to be talking about his new book. We did record an episode with Paul almost exactly two years ago, Unpossible, and that was about his previous book, which is called Endless Universe, which he co-wrote with Professor Neil Tarok at the Perimeter Institution. And that's sort of about a very interesting idea for cosmological origins and the pursuit of scientific knowledge very much at the heart of what I do as a professional experimental cosmologists looking for signals from the very early universe.

That book is very influential on my career and many of my colleagues. And this one, I have to say, is going to be influential to a whole host of people, ranging from my children to many children around the world. And it's already, I should point out, I should give you a congratulations, it's already number one on Amazon in the mineralogy category. So that's a first for me. You're truly a rock star now, Paul. All puns intended.

So first, since the book, I have not yet read the book. I've only read the sample chapter. I'm awaiting my copy to be delivered physically and wirelessly later on tonight. But I wanted to have you explain a little bit of the overall theme of the book and how it came to be and what prompted you to write it, not giving it away. I always hate when you do an interview with a podcast. and they say, tell me everything about the book that the reader could possibly learn

without having to buy the audio book or the physical book, which no author wants to hear. So I want you to wet our appetites for this phenomenal book, which we're eagerly anticipating, receiving very soon. Well, I'll do my best. So thanks for having me, Brian. Yeah, so the book is a very unusual science story

that is at one level. It's a story about a new form of matter that was once believed to be impossible. Actually, for hundreds of years, we thought it was impossible for atoms and molecules to form this form of matter that we today call a quasi-crystal. It begins with the origin of that idea,

which I was involved in back in the 1980s. And then it turns to the story of where we might find these quasi-crystals. They were first found in the laboratory, around the same time that we were speculating about this hypothetical possibility of a new form of matter. And then the question arose in my mind, whether or not nature may have made this form of material before humans did, before we made them in the laboratory. So we, you know, back in the 1980s, we had a sort of mathematical or hypothetical idea,

a group working a few hundred miles to the south of us, accidentally discovered such a material, in the laboratory. That's how the subject was born, just by a coincidence. But then the question arose, maybe nature made them before us. And if so, we would we look for them? And that's kind of a, where do you start to look for a new form of matter that you haven't seen before? And by the way, why haven't you seen that form of matter before? If it's possible, if we can make it in the laboratory, how is it we haven't seen it in nature already? And so that's, that was a quest that began around 1998, it's formal, as a formal quest. And it's been continuing for the last 20 years.

And it's a story which is, you know, part science story, part detective story, part mystery. It involves KGB agents and smugglers and and all kinds of other strange aspects, missing persons and strange Romanians and all kinds of other aspects you don't normally see in a science story, even bears come into the story. So it has a little bit of everything. And at the bottom of it was a search as to whether or not these natural quasi-crystals, whether the quasi-crystals, this new form of matter really can be found in nature or not. And the story then goes on to tell how we discovered it was found in nature and where we found it. And what's so interesting to me is, yes, you've been called many things in your career.

And I think one of the most flattering and sort of the one of the most envious about is Indiana Steinhart. And that is, can you give a little bit of an insight as to why you'd receive such a delightful moniker? Well, so the part of the story I didn't tell you was where we had to actually find this strange new mineral. And the answer after a long novelesque story of tracing down a grain that was found in a museum basement in Florence, Italy, to figuring out where it came from, eventually took us to a very remote, uninhabited region of the Comchatka Peninsula. not the part that we're familiar with that sticks out with the sea of a Kutsk that is today even tourists can go there but a part which not even Russians can normally visit the northern part of it of the Kamchaka peninsula just across the Bering Strait from Alaska a part that's called Chukotka and in the mountains of Kukchukka far from any inhabited region it turns out

in a small stream there that turned out to be the place where we were We were able to find new grains of this strange material. And we had collected through our detective story a number of hints that it might be there. But the only way we could prove it was there was to actually put together a team of geologists who would join with me and go out into the middle of nowhere, fly to the far eastern Russia, the farthest most eastern part and northernmost part of Russia, beyond Siberia, to the Khamchatka Peninsula and travel by by a strange form of transportation to the mountains and we spent about a dozen days there looking for grains of this new material collecting lots of samples and fortunately

we came back and actually found these grains and from those were able to learn where they came from originally and one of the things I remember you've given a couple of just extremely fascinating talks about this in the last, you know, almost two decades or more than two decades since you started this mystery adventure story in your career. And one of them that really spoke out and is really eagerly anticipating reading, as you know, I'm a student of sort of scientific heredity and how a scientist becomes a scientist and more than just their natural, raw, intellectual horsepower, but that, you know, at least maybe your Russian, you know, colleagues, if they're free from KGB influence, can tell that the word scientist, when translated in Russian,

means someone who is taught. And it literally, you know, reflects the process by which in science, I believe that science is actually communicated from human to human, not from, you know, Wikipedia page to Wikipedia page. And the book opens, at least from the sample chapter that I had the opportunity to read with a description of one of your great scientific mentors, which is Richard Feynman, one of the greatest physicists maybe in history and certainly of the 20th century, and that he was one of your mentors and advisors as an undergraduate and obviously maintain close relation with him. And so I want to ask you about that. And then I want to connect it to another character who recalls central to this story, which is your graduate student,

Dove Levine and what later kind of influence he had in the field of this of this magical new form of matter, which is really, as you say, thought to be impossible. So before you end to that, can you explain what does it mean? Where did this title come from? Our listeners may be interested. Why is it the second kind of impossible? What is that? Yeah, so the title refers to the idea that when you're trying to look to make a new discovery

in science, I've, to me, to me, What I always pay attention to is whenever someone tells you that something is impossible. So sometimes when a scientist says something is impossible, there are really solid reasons why it is impossible. It's absolutely violating something that we know to be true, that we can prove is true, and there's no loopholes around it. So an example of that is if I were to give you a bunch of, that's a say squares and asked you to tile your floor with squares, you know you could do it and fill the

floor without any gaps. But if I gave you a bunch of perfect pentagons, regular pentagons, that's mathematically impossible. You cannot fill the floor with pentagons without having spaces between them. On the other hand, sometimes when scientists say something is impossible, they're saying it's impossible based on some assumptions that they're making that maybe they're not even aware of. They're so common and so apparently true that they just take it for granted and then they reach a conclusion from that. So, for example, one of the things that we've known in science for centuries is that atoms and molecules like to come together just like tiles. And so if you, as to say crystals, for example, are formed building blocks, similar to tiles, which just

joined together, you know, edge to edge to fill a solid and make the crystal. And we know that accounts for many of the properties of crystals, including the way they facet and form those nice, beautiful facets that we're all familiar with and that we find attractive. And it also affects a lot of their electronic and physical properties. And so for a long time, we believed, just like we can put squares together to make tiles, we can put atoms and molecules together to make crystals. But there are certain shapes which are absolutely forbidden. For example, you cannot have any form of matter which has facets, which have perfect pentagon shapes, for basically the same reason that you cannot tile a floor with perfect pentagons.

And that was an absolute rigorous law of matter that everyone learned when it was. studied matter for the last several hundred years. This episode is brought to you by Netflix. Most valuable promotions in Netflix are hosting a blockbuster triple headliner Saturday, May 16th. Rhonda Rousey returns to face fellow woman's MMA pioneer Gina Carrano in the main event. Plus co-main's Nate Diaz versus Mike Perry and the best have you wait in the world, Francis Ngano versus Felipe Lince.

Watch Rhonda Rousey versus Gina Carano, live only on Netflix. Saturday, May 16th at 9 p.m. Eastern Center time, 6 p.m. Now, the question is, is that really impossible of the sort that is absolutely rigorously true, or have you made some assumption? And it turns out you have made some assumption in the second kind of impossible. You've made an assumption that matter only can form a single kind of building block, just like a single pentagon or a single square. Another logical possibility once you think about it, is that suppose matter forms, let's say, two different kinds of building blocks, two different shapes. And they don't repeat edge to edge, you know, one after the other,

but they repeat in a complicated sequence, the sort of two different frequencies, at two different sets of intervals. Turns out you can then make something new that people hadn't considered before called a quasi-crystal, a new form of material. And so while it was thought to be impossible to have any material with five-fifference, facets. That turns out to be the second kind of impossible. The kind of impossible that was based on an assumption that turns out not to be true. Matter doesn't have to form that way. And it can form, therefore, all kinds of new shapes that we thought were mathematically forbidden. And it's not just one shape, not just, I'm focusing on the pentagons because those were the first examples found. But before the discovery of quasi-crystals, there was really only a small,

number of different possible patterns that we thought matter could make. We discovered that we were missing an infinite number of possibilities. And we've only discovered a few new possibilities so far, but we know that they're beginning, that's the beginning of an unbounded set of new shapes and possibilities. So they're the example of the second kind of impossible. Something that you thought was impossible, but actually when you find the late, when you look at your assumptions and you find the loophole, you can discover something dramatically new. So it's almost the second kind is really a pre-reflects a prejudice of the one who's interpreting or claiming the impossibility, whereas the first kind might be imposed by nature

or in herself in a certain sense that you really can't accuse of being prejudice, except that it displays certain types of phenomena. Is there a third type of impossible that you're aware of? Is that AI? Well, maybe some future book will. But I don't know of one at the moment, at least for my thinking, as ordinary human scientist thinking, I'm usually trying to decide when so when I hear the word impossible, my ears pick up, and I'm really trying to always imagine what has the person assumed to reach that conclusion.

And can I just imagine there's something different, something different that's something that might be altered about that assumption? And if so, why that would be interesting? So almost all the time I'm listening to a talk about anything in science, any topic in science. I'm kind of listening with two ears. I'm listening on the one hand for what the person's saying, but I'm always asking myself that question. What have they assumed? And could it be wrong? And then could that lead to something interesting?

Yeah. In fact, the name of our podcast into The Impossible really traces from an Arthur. See Clark quote, which says something to the effect that the only way to find out what's possible is to venture a little bit into the impossible, which really belies, you know, as you're saying this, the second, the second form of impossibility. I think people really, you know, artificially constrict themselves by imposing certain types of biases, et cetera. I mean, some are basically rules of thumb that for some reason get elevated, as you point out, you know, even the great Richard Feynman, who I want to get back to now, you know, had when you first presented this, which must have been

just the most kind of surreal experience to be back in the presence of your mentor, you know, but as a peer and as a, as a scientist with, you know, abilities equal to and, you know, in some ways to what Feynman was capable of. And then to have him seemingly crushingly, you know, critique your result in, in the audience, you know, afterwards, you know, as impossible, right? And how were you able to sort of persevere, you know, through that? Was it just the strength of conviction that what you had claimed? Because at that time, there were no natural or artificial, you know, kind of examples, right, of what you were conjecturing, at least in terms of, I mean, you had shown that there were mathematical possibilities for it.

How do you handle such, you know, critique? I mean, luckily, he was, you know, had sort of a nabuncular, you know, feeling for you. But, you know, how was that? I mean, a lot of people would have gone into a vast amount of psychotherapy of Feynman told them what they were saying was stupid and impossible. How did you handle that? Well, yeah, fortunately, it was not my first experience with Feynman, or I think I would have, you know, just shrunk under the desk or something like that. So this was a few years after I had been a student at Caltech and had a number of interactions, close interactions with Dick Feynman. among them, well, first of all, he is the person that really brought me into physics.

When I went to Caltech as an undergraduate, I didn't really know much about physics at all. For some reason, that was just a missing part of my science education, or a weak part of my science education. Within a few weeks, I encountered Feynman and Feynman lectures on physics, and I was converted. I didn't know exactly what I wanted to do in science or in physics, I should say. But I tried to watch closely, Feynman, who was my hero, quickly became my hero, to see, you know, which way he would point, appoint me. And one of the things I did when I was a

junior is with my roommate, we went to visit Feynman. We asked him if he'd be willing to give a course that came to be dubbed physics X. Turns out he had done something like this a number of years ago, a slightly different format, but what do you come and give this course, physics X, in which you'd come each week, it's an unofficial course, wasn't on the registrar's list,

and you'd just come and talk about whatever you wanted to talk about, whenever physical phenomenon you wanted to talk about. And so that's what happened. Every week he would come, and you'd come and ask him a question about something. It had to be something about something you observed in nature or you knew about existing in nature,

and he would do his brief, best to tackle it. And what I learned from that was, what I expected to learn from that interaction was that he would be pointing heavily to the work he himself had done in elementary particle physics. But in fact, we hardly discussed particle physics at all. The subjects roamed all over the map. And every subject was fascinating. So what I learned from that is that physics, the opportunity for physics discoveries can be found everywhere. in everything. And everything is interesting.

Everything was interesting to Feynman, so everything was interesting to us. And he could just, you could describe everything in such a way that, he could tackle anything in such a way that it was fascinating and captivating. And that was an important influence on me, because in my own research,

I kind of followed a path that began with particle physics to begin with, but then it soon began wandering to other areas, such as the topic we're talking about, the topic of this book. But in another, interaction with him. I was doing some research with him on various topics. And, you know, Feynman was known for giving people a really hard time in lectures and calling them foolish and stupid and things like that. And so, you know, I had some of that. I'd come to his office and present an idea

and he explained to me an idea whether that it was foolish or stupid. But, you know, to me, it was always, it was never insulting. It was done in a certain, you know, a certain way of enthusiasm. I mean, it was consistent. But what really convinced me that it was, you know, I should take it in stride was there was one time when, you know, he accused me of something, getting something stupid and wrong. And it involved a super ball and the way a super ball can spin and bounce. And fortunately, I had a super ball with me. And I demonstrated to him that, in fact, I wasn't sure I was going to work out. We tried the experiment that he was proposing.

And sure enough, it turned out what I had predicted in my equations was correct. And he turned around and said, ah, stupid, referring to himself. And then I realized he would use that term for anybody who got something wrong, more to jolt them into paying attention. Something interesting was going on here. You ought to pay attention and not simply overlook it because it's something to be learned here. So, okay, so years later, I'm giving this talk that you're describing, this lecture, one of these early lectures on quasi crystals.

And Feim was in the audience and listening very attently. And I was expecting him to interrupt, but he didn't interrupt at any time during the lecture itself. He waited until it was over. And he came up and said, well, this is impossible. You know, people were leaving the room, but it echoed throughout the room that, you know,

it was clear that, you know, Feynman was objecting to this idea that there could be this new form of matter. even though I had done my best to present, you know, lots of evidence of it, including even in demonstration of it. But I could tell from his smile that it was the impossible like, you know, like he would call me stupid or something impossible in the past. He was really challenging me to prove my point.

And what he then asked me to do was I had done a demonstration in front of the lecture to show what happens when you shine, well, it would be like if you shine electrons through such a hypothetical material. In this case, I was using a laser and a slide, which had the same pattern as the arrangement of atoms would have in the material. And what I had shown is that had produced a pattern that was supposed to be impossible according to all the standard textbooks on solids. And that was the point of the lecture, that there are these new possibilities that had been considered impossible or they were now impossible. So having declared the whole idea impossible, he then walked out to me and said, I want to see that demonstration again. So we

turned off the lights, we turned back on the laser, we did the demonstration again. He looked back and forth between what was on the wall and the laser. He picked up the slide, he looked at the slide, he put it back in. And yeah, he said, you just give a huge smile. That really is impossible. And that was, you know, and then slowly walked out of the room with a big smile on his face. And so I felt there was my chance to sort of return a favor that he had given me and giving me so many thrills in physics. It was my chance to return a thrill to him. And I think appreciated the present. Yeah, I mean, that kind of goes along with my, you know, never told you this, but my impression of you is you're sort of a happy warrior, you know, sort of of science,

where you really just are mischievous and playful and you don't do stuff for personal gain, although, as we'll hopefully get to, there are things, you know, that could lead to potential financial or technological improvements based on your predictions, your theory, your experimental little findings. And, you know, I think that's important to think about, but you seem to do things for, as Feynman would say, you know, the pleasure of finding things out rather than some implication or application. And I wonder, you know, when you were supervising your own student, I mean, you're very unlike Feynman in terms of, I think, you know, he was very rough around the edges and he might have been had a warm heart. I never knew him, but, you know, he might have had a,

but it would be hard to discern that from the outside. He was very, uh, he was very, uh, shrouded in sort of a mythology that he helped to cultivate and is partially responsible for why his books and books about him and multiple biographies and autobiographies have been written about him. But when you were working with your student, was there ever a time, this is Dove, I'm speaking about, was there any ever a time when you actually worried about his career? Like what he, it's one thing for you, you know, you're this esteemed scientist even by that point.

But what about him? kind of obligations or what kind of risks are appropriate to assign to your students or the people that you mentor, you know, on your behalf, you're not always going to be there to fight their battles. And so how do you juggle that? Because it could be risky, right? You mean to do high risk science, how do the higher risk science? Avairest kind of, you know. I think science is only worthwhile if you think you're taking some risk, especially as a theoretical physicist. Well, I think both is a theoretical physical physicist and as experimental physicist, you're taking risks. You're taking different kinds of risks.

As a theoretical physicist, you're taking a risk of your ideas. You're putting in an idea that might make you look stupid. It might be wrong, stupidly wrong. It might just be something inconsistent with it. Or it might be logically possible, but nature just didn't choose that course. On the other hand, there's that thrill if you are lucky enough to come up with an idea, even a tiny idea, you know, that you then discover is actually the way nature works. I just find that to be just, that's what that really, that's the moment that really draws me to science. What I really love most is that brief moment,

even for a small idea, where you feel, you realize you discovered something that no one knew before and you're actually the only person on the planet that knows it, probably. And maybe in a bit later you're gonna share that idea. But I actually don't relish sharing that idea immediately. I like to just enjoy that moment for a bit and think about it. And before I release, you know, before I, before I sort of release the idea into the,

into the world. And that's worth everything to me in science. And so I try to, by example, try to bring that to my, to my students to, first of all, question, you know, the things that we assume to be true. See if you can find some, some new way of thinking about it that, that can lead to a new idea. Learn how to become disciplined in terms of the use of mathematics and logic to work out your idea. And then to be very serious about experiment and observation. Take it seriously if the observations or experiments go against you.

Try to resist patching and fixing an idea and adding bells and Wilson to it. it if nature is not agreeing with it. Respect nature as the arbiter. I try to communicate all those ideas, depending upon where we are at a given stage of a problem or a question that we're asking. Yeah, I find it interesting. I was talking on a podcast I was doing with someone else today about how, you know, the difference between, he asked me, what's the difference between being a theorist like

yourself and an experimentalist such as myself? You know, is it like being a Democrat and a Republican? Kim. Well, not really. I mean, we both study polarization, but it's a different kind of polarization than political polarization. It's a good kind of polarization. But we came to the conclusion that's more like, you know, kind of the offense and the defense of a football team, you know, where they both have a common goal. They have very different tools and techniques. They're not competing with each other, but, you know, they both have a little bit of a swagger and they both have a little bit of a chip on their shoulder, something to prove.

I don't know which of the two of us would be, you know, kind of the, you know, the, offense versus the defense. I view the kind of experimentalist, though, if I interpret what you're saying, is sort of the gatekeepers, you know, the ones who are going to be work on behalf of of Mother Nature as arbiter, you know, kind of present the evidence. Of course, we make our fair share of mistakes too, and we are subject to exactly the same kinds of biases. But there is sort of the sense, you know, to use Nicholas, or Nassim Nicholas Teleb's phrase and also one that Jim Simons likes to use a lot of skin in the game, you know, that you can create a lot of theories as a theorist. And, you know, if nobody, you know, if you get one right, so to speak,

whatever that means, you'll get enough attention that could make your whole career, right? Or if it becomes so influential that even if it's not proven or more aptly falsified, you may enjoy a very long and productive career. On the other hand, if you keep having experiments that keep failing and not producing results, you're not going to have a very long career. And so there are some elements of that. And you can't just have a strong offense. You can't just have a strong defense.

They kind of have to work together. But it seems to me that experimentalists might have more need to think about the skin in the game as you're talking about. There is this investment. Of course, that comes with the challenge that we may be, you know, kind of influence to, to interpret our results in a way most favorable to a prevailing field or theory. And I wonder, you know, in your career, which, you know, you're still young, but you've seen, you know, you bridge the gap from the, you know, the greatest physicists of the 20th century and now into the 21st century that you're helping

to lead at the vanguard. I mean, what do you see is a difference between the way that theoretical physics works? There's a book now called Lost in Math by a physicist named Sabina Hassanfelter in Germany. It was very critical of modern theoretical physics. Of course, she gives a real short shrift to experiment, but she, which, I think is blossomed in astronomy and cosmology, experiments in particular, of course, I'm biased. But she really says there haven't been any new theoretical developments in physics since the mid-70s. I wonder, A, do you agree with that? And B, do you think that's a symptom of something

if you do agree with it? Or is there something else going on in the culture that we need to be aware of it? It's only getting every customer's order right. It's only a point-of-sale system connected by Spectrum fiber-powered business internet, helping you track hundreds of secure transactions. And it's all backed by 24-7 U.S.-based customer support and local technicians. It's only everything. Get business internet advantage free, forever, when you get four mobile lines from Spectrum. Visit Spectrum.com slash free for life to find out how. Restrictions apply. Service is not available in all areas. That's a good question. I think there, um, I think there, um, I think

that the last few decades has been unusual in the course of theoretical physics. I think, you know, when I was coming into the field, up until the time I was coming into the field, I think there was very close interaction between theory and experiment, both in the areas of fundamental physics and there was soon to be in cosmology, say particle physics, fundamental physics, and cosmology. And I think that the, you know, beginning in the 1980s, there were two prevalent ideas that began to take over many people's thinking, one of which was what we call super string theory or string theory as a possible description of the fundamental forces and constituents of nature.

And the other in cosmology, this idea of inflationary cosmology, the idea that we can explain why the universe is the way it is, because the universe after the Big Bang underwent a period of rapid stretching or accelerated expansion that smoothed it out. And these ideas propagated in a way which didn't, on the string theory side had very little connection with observation because string theory more or less involves energy scales that are beyond our direct testing, but to the degree to which it had some implications, some strong suggestions of what we

should see. What we learned over the last decade since then is that essentially all those suggestions have not worked out. So string theory suggested that we should have a whole new set of particles called supersymmetric partners that were supposed to be observed at the large Hadron Collider at CERN. We don't see those. It's suggested that dark matter is probably a particular species of particle called a WIMP, a weakly interacting mass of particle. We don't see that. It is an idea which is hard to accommodate with the idea that we read, the observation that we've discovered since the, since the introduction of string theory, the discovery of the

universe is undergoing a period of accelerated expansion. That seems hard to accommodate in string theory. The idea of inflation seems hard to accommodate in string theory. And yet, the idea is still prevalent today. It's prevalent because several generations of young theorists have been told from the start that, you know, this is the only idea we have for making a unified theory of quantum physics and gravity and the other interactions. And perhaps it's so.

But when you have a track record like that, you would expect under healthy conditions, There should be other ideas out there. There should be a healthy opposition that says, well, here's some competing ideas. And I think that one of the things that's happened in string theory, and I'll talk again about cosmology at a moment, is that there's also a strong, there's a new element in the game,

which is a very strong social network. It's related to the Internet, and it's related to the way the field has self-organized itself. It has a very strong sociopolitic, political component to it as well as a scientific component that strongly encourages students to, you know, to take this idea and assume it as an essential ingredient from the start. So I understand that they're enthusiasts, but it disturbs me when I hear a young person begin with a statement like, well, we all know string theory is the correct description of the universe.

Based on what? Why aren't you questioning that assumption? It goes back to the second kind of impossible. idea. If that is what you're being told, you should be challenging yourself to ask, is that really true? What really makes me believe it's true? Is it because authorities are telling me that? Or can I think of any other way around it? It just surprises me that there isn't more competition. There's a similar story in cosmology. The story is a little bit different. Their inflation began, the idea of inflationary universe idea began as a rather simple and compelling

idea. In fact, it was a study of inflation that brought me into cosmology in the first place. But what we discovered over the years is two interesting things. Number one, that the early ideas that we thought inflation would, are any ideas of inflationary cosmology and what it would predict? Those predictions turned out to be verified by observations so far, with one notable exception. On the other hand, We learned that the theory doesn't work the way we thought it did. It doesn't make those predictions at all. We had not properly understood how the theory would work,

what the role of quantum physics would be when combined with gravity when you have inflation involved. And so at the same time, the justification for those predictions has disappeared. We really need a new idea. And again, you know, what's happened in the field is that because our early misconception of the inflationary theory led to so-called predictions, what we thought were predictions that turned out to be true, many people just take for granted that the theory must somehow be right,

even if our understanding of the theory today doesn't correspond to our early understanding of it. As to say, the predictions can no longer be justified as coming from the theory. And again, there's just two few people who are challenging the idea that we have to have a big bang or that we have to have inflation, even though those ideas are not really explaining the data that you and other colleagues of yours, the experimentalist and observers, are finding. In fact, one of the things that inflation would generally predict is that you should have had a spectrum of gravitational waves that should have been cosmic wavelengths, cosmic scales, and they should have been strong enough to be observed today.

And so far we're not seeing them. And that's, you know, even observationally, a direct challenge to the theory. And nevertheless, what you see is that what most people are doing, including most young people, is they're just trying to add bells and whistles to the theory that will help it to evade the current observational constraints or the next round of observational constraints, rather than ask the obvious question, which is, is it possible that the ideas in which we've been assuming all along or, wrong. And if so, can we use the observations we have to come up with a new and better idea? So it's been a strange period where strong social networks and, you know, supporting these different ideas and the way, in fact, supporting the two of them together oftentimes, you know,

has helped support ideas when I, there certainly has to be opportunity for new ideas, given what we've learned. Yeah, it's interesting. Especially challenging when I tried to convince you to get a Twitter account recently and was met with strong opposition to certain social networks. But see that as it may. I think you'll do quite well without such a contrivance. I think it's interesting just hearing you talk and just really thinking about it for the first time with your first book, which is really showing the impossibility of feeling that everybody thought was mandatory to now going to showing the possibility of everything, something that people thought was forbidden. It seems, it seems, you know, almost like a theme.

that one can pursue sort of and should pursue for, you know, the, the, to the profit of the pursuer, perhaps, you know, the contrarian point of view. It seems that is, you know, not being contrarian for a contrarian sake, but I think that seems to be a core message of your work in this book that, that people, you know, taking, sometimes taking the oppositional viewpoint, even and having confidence, which I think you can only get confidence based on, you know, prior prior successes. So I don't think, you know, someone should come in and just be incredibly confident about his or her abilities. But I think that you've proven that to be quite a fruitful avenue. I want to finish the discussion today, getting back to the book, the new book,

the second kind of impossible, which is Professor Paul Steinhart's new book, the extraordinary quest for a new form of matter, which I think is such a sweeping concept. And, you know, I saw, I have the benefit of having not read the book, but seeing the, seen the movie, seeing the, the colloquium about it and just being riveted as everybody was. And, you know, this really, the quest takes us on a journey from, you know, the ancient Greeks and their, they're sort of obsession with mathematical beauty and purity, which would sometimes lead to actual, you know, fundamental results. I mean, they would show the Pythagorean solids and it's not like we'd added new, you know, Pythagorean solids that they could have known about that they didn't discover. Obviously, has direct applicability to the crystal graphic structures that you describe in the book. And I think the Greeks in contradistinction to the Romans and the Roman school was, you know,

the Greeks couldn't get enough theory and pure abstraction. And the Romans couldn't have any of it. You know, they wanted to build aqueducts and actually do things that was, practical and useful to humanity and to their subjects. And so you did that in your book, not only literally going, you know, working with Italian archaeologist and so forth, but really looking into this finding,

you know, kind of the natural and the artificial occurrence of these objects, these quasi-crystals, which really, to impress upon the listener of the podcast, is truly, as the book's subtitles, says a new form of matter, which is wholly unexpected and delightful and you have many illustrations in the book, which make it very visually compelling and beautiful even. I think one of the things that always speaks to me as an experimentalist, someone who's dealing, you know, skin in the game and trying to build stuff that actually works and returns

results on a 10-year track life cycle. The thing for me is, you know, to what extent does our research is, you know, our research as physicists have to be practical. And it turns out that these results, and maybe you can briefly explain the results that may have commercial applicability or viability, and then whether or not, you know, is that important? I personally think it is, but what are your thoughts on that? We've never discussed that. Okay. Well, first of all, let me make the, just to elaborate a bit of what you're referring to. So, as I mentioned earlier, if you have matter in which the atoms and molecules or structures have a new novel kind of arrangement that's

mathematically different in a fundamental way. We know that those same mathematical properties have physical implications. It means it's going to have new physical properties. So one of the things that, you know, we showed about quasi-crystals many years ago is that it generically going to be stronger and less plasticly deformable than ordinary crystals are. And that gives them certain advantages in structures, structural applications. And that's some of the first applications that they've had. But probably the more interesting properties are going to be how they affect the flow of electrons, their electronic properties.

Or more recently, we've been thinking about how, artificial quasi-crystal structures that we could make in essentially what we call electron lithography machines, which is like a very high-end 3D printer, how we could make 3D printed patterns in a quasi-crystal pattern, would have a unique effect on the flow of light through them. So if they would effectively act like semiconductors for light. So we know in electronics, semi-conductors are extremely important in transistors and essentially all of integrated circuit technology and all the technology that underlies our cell phones and our computers and our communication devices is based on electronics and in particular the role of silicon and germanium and other semiconductors in being able to modify, trap, change, and alter the flow of electrons is a crucial. to that technology. But one of the goals in the future is to develop even faster devices. And faster than electrons through materials is light. And so there is this vision that has been pursued for the last

few decades of replacing electronics with photonics. That is to say, light circuits rather than electronic circuits. So, for example, the first thing you're going to need is something that's analogous to a wire in which the light can simply flow. Well, we know what those are. Those are fiber optic cables, and we know that they exist, and they're already being used quite a bit in our everyday lives, for example, in bringing images and television to our homes. Now, the next thing you're going to want beyond a wire is to create something that's analogous to silicon, a semiconductor for light, something that plays the same role of light

for light that silicon does for electrons. And it turns out that a quasi-crystal structure is advantageous for acting like a semiconductor for light. It has just like a semiconductor has something called a band gap, a perfect semiconductor has a bandgap, a range of energies which are forbidden to flow through the material if it's perfect, the same is true for the quasi-crystal. And then, just like we dope our semiconductors and produce defects in them intentionally, in order to be able to control and manipulate the flow of electrons, something analogous exists for light in quasi-crystals.

But quasi-crystals have the advantage of crystals in that they can be made much more spherical than crystals can, which means that the flow of light is the same, no matter how it comes in and out of the quasi-crystal, nearly so. Whereas for a crystal, it's very delicate. You have to align the light. If you were going to try to make a photonic crystal, you'd have to align the light coming in and out very carefully. If you try to make a photonic quasi-crystal, such careful alignment is not needed.

And so that's opened the way for a new technology that we're pursuing, which is to use these quasi-crystal patterns as a template for making light semiconductors. And it's also led to other new forms of matter, if you like, hypothetical forms of matter. that we're also pursuing which are neither crystal nor quasi-crystal, but yet something different again that we call a hyper-uniform disordered solid. And they also have, you know, interesting properties that are different than either quasi-crystals or crystals. And they, too, just like quasic crystals come in a whole zoo of possible symmetries,

these other solids contain or have a whole zoology of different possible properties as well. So what I really love about this subject is you begin. with something in your head, a mathematical pattern, something geometrical. You can turn it into something real. Once you can show you can make it something real, it can become a new material. With the age of 3D printing and also being able to control atoms at the atomic scale and how they're arranged, we can actually make those materials rather than wait for some chemists to figure out how to do it. And then you can, it can next be some practical device. So I find that just as exciting a discovery for sciences, other things that I do.

just to find something that came out of your head, you know, might have some application or some very unusual physical properties that we thought were impossible before. Yeah, that's phenomenal. Yeah, as a layer of instant gratification that you can't be said of cosmology, you know,

you usually get the instantaneous gratification or near instantaneous, usually almost eternal. Well, Paul, it's been just fantastic talking to you as always. And the book, I want to remind people, it's called The Second Kind of Impossible, which will be out by the time this podcast is posted. It's the extraordinary quest for a new form of matter, written by Professor Paul Steinhart,

Albert Einstein Professor in Science at Princeton University, published by Simon Schuster. And I just want to express my gratitude for you being on the podcast and my expectation that in the future, Harrison Ford will be known as the Paul Steinhart of archaeology rather than the Indiana Jones of physics. So Paul Steinhart, thank you so much, as always, for your graciousness and very stimulating conversation.

Well, thanks, Brian. Thanks very much for having me on the podcast. The only thing we can be sure of about the future is that it will be absolutely fantastic. Five, four, three, two.