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What are quantum glasses? · Daniel and Kelly’s Extraordinary Universe

0:09
Speaker 1: Daniel, where are you recording the podcast from these days?
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Speaker 1: Today I'm in my office at the university. Kind of disappointed.
0:15
Speaker 1: Wanted you to be like at the control center of
0:18
Speaker 1: the L C or right next to where the particles collide,
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Speaker 1: kind of like a sportscaster. Nothing so glamorous, but I
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Speaker 1: mean pain a picture for us. What is your office
0:28
Speaker 1: look like? Is it like in a dark dungeon, or
0:31
Speaker 1: is it at the top of the in the Penthouse,
0:33
Speaker 1: at the Corner Office? You know, something in between. I've
0:35
Speaker 1: got a nice window here with a view outside of
0:38
Speaker 1: the southern California landscape, but it's not like the biggest
0:41
Speaker 1: office on the floor. We've got some real big shots
0:44
Speaker 1: around here. You're more of a meeting shot, small shot.
0:49
Speaker 1: I'm a just right shot, your podcast shot now. Is
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Speaker 1: Everything in your office super organized, or are there like
0:55
Speaker 1: huge stacks of papers everywhere? Well, I'm not the kind
0:58
Speaker 1: of person who's at risk for because his desk collapses
1:02
Speaker 1: under a huge tower of papers, but it's not exactly
1:05
Speaker 1: like a well organized museum or anything. It looks lived in.
1:08
Speaker 1: You know, I think lived in his code for missing.
1:12
Speaker 1: I don't know. What do you call something that's like
1:13
Speaker 1: halfway between being neat and missing. Well, I'm a physicist,
1:17
Speaker 1: so I would call it a phase transition. It's like
1:19
Speaker 1: a melting point. You're kind of like a slush, like
1:22
Speaker 1: a slushy. I'm hoping that if they crank of the
1:25
Speaker 1: A C maybe my office will organize itself into a
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Speaker 1: crystal and you'll freeze to death, also for serve for
1:31
Speaker 1: future generations, but at least I'll look neat doing it
1:34
Speaker 1: and you'll be pretty cool too. Hi, I'm poor. Hey,
1:51
Speaker 1: I'm in a cartoonists and the CO author frequently asked
1:54
Speaker 1: questions about the universe. Hi, I'm Daniel. I'm a professor
1:57
Speaker 1: at U C Irvine and a particle is this who
2:00
Speaker 1: worked at the large Hadron collider and I like to
2:03
Speaker 1: think of myself as just messy enough, messy enough for what,
2:08
Speaker 1: before not being neat, messy enough to have that lucky
2:11
Speaker 1: stroke of insight, you know, when that pile of notes
2:14
Speaker 1: you took three years ago at a seminar just sort
2:16
Speaker 1: of falls into your view and provides that crucial piece
2:18
Speaker 1: of information to unlock the puzzle you're working on. If
2:22
Speaker 1: you're too neat and organized and everything's tucked away and
2:24
Speaker 1: you never have that sort of serendipity. I see, and
2:26
Speaker 1: I assume that because your scientists, you have this tested right,
2:30
Speaker 1: you've a scientificity proven, like you've done the control of
2:32
Speaker 1: studies where you're really neat and more missy. Yeah, I
2:36
Speaker 1: have a bunch of other Daniels in the basement and
2:38
Speaker 1: I make them be really neat and messy and I
2:40
Speaker 1: keep track of their careers also, and I guess you're
2:42
Speaker 1: the most successful one because you're not at the basement right,
2:45
Speaker 1: so that proves your theory. I guess I'm the only
2:48
Speaker 1: one with a podcast, which maybe means I'm a failure
2:50
Speaker 1: as a scientist. I'm not sure the other ones are
2:54
Speaker 1: actually doing physics. Is that what you're saying? They're still
2:57
Speaker 1: newon research exactly, but anyways, welcome to our PODCAST, Daniel
3:01
Speaker 1: and Jorge explain the universe, a production of my heart radio,
3:05
Speaker 1: in which we try to find order in this messy universe,
3:09
Speaker 1: this chaotic swirl of particles going to and fro weaving
3:12
Speaker 1: themselves together into this incredible, beautiful reality that we want
3:16
Speaker 1: to make sense of. While galaxies smash into each other
3:20
Speaker 1: and particles annihilate each other, we step back and try
3:23
Speaker 1: to organize all the things that are happening out there
3:25
Speaker 1: in the universe into a crystalline set of ideas that
3:28
Speaker 1: we can transmit along these audio waves into your brains.
3:32
Speaker 1: It's right, because it is a pretty messy universe, full
3:34
Speaker 1: of amazing and exciting things happening out there, particles crashing
3:37
Speaker 1: into each other's black holes sucking up things. And yet
3:40
Speaker 1: somehow we have, as humans, figured out that there is
3:43
Speaker 1: a little bit of a order to all of this,
3:45
Speaker 1: even if we aren't very ordered ourselves. And of course
3:49
Speaker 1: we don't know if that order exists in the universe
3:52
Speaker 1: or if it's just something we have imposed on it.
3:54
Speaker 1: Does the universe actually makes sense? Are we just telling
3:57
Speaker 1: ourselves these stories of UN in the philosophy of physics?
4:01
Speaker 1: But so far it works for us. It lets US
4:04
Speaker 1: build airplanes and transistors and all kinds of new materials
4:08
Speaker 1: that ruin and save our lives. Are you saying the
4:11
Speaker 1: universe is just messy enough? I'm saying it melts my
4:14
Speaker 1: brain sometimes melts in your mouth. All that knowledge, I wonder,
4:17
Speaker 1: what would you like if the universe melted in your
4:19
Speaker 1: hand instead of your mouth? Well, first of all, can
4:21
Speaker 1: you hold the universe in your hand? Only has a
4:23
Speaker 1: thin candy coating, right, but you are in the universe
4:27
Speaker 1: also putting your hand the inside the Eminem two. We
4:31
Speaker 1: are all EMINEM's. That's the philosophy on this show. But
4:34
Speaker 1: are you the chocolate or are you the candy? and
4:35
Speaker 1: which color is your eminem? Knowledge is the chocolate and
4:39
Speaker 1: this show is the candy coating. That helps it go
4:42
Speaker 1: down smooth keeps it from melting in your mouth or
4:45
Speaker 1: in your hand exactly as you crunch on through it,
4:48
Speaker 1: or in your ears. That would be pretty messy. You
4:50
Speaker 1: know what melt the chocolate in your ears. Are you
4:52
Speaker 1: suggesting people do or do not put Eminem's in their ears?
4:54
Speaker 1: That's sort of lost track here. I know children do
4:57
Speaker 1: and we have kids listening. Are you saying you know
5:00
Speaker 1: the results of that experiment, that if you put Eminem's
5:02
Speaker 1: in your ears they do not melt? I can guess
5:06
Speaker 1: what happens, but thing it's science is not about guessing.
5:09
Speaker 1: It's about going out there and doing experiments and discovering
5:12
Speaker 1: what actually happens when you make new arrangements that nobody
5:15
Speaker 1: has ever thought of before. Sometimes it's adding weird metals
5:18
Speaker 1: to other metals, sometimes it's putting eminem's in ears. That's right,
5:21
Speaker 1: because we know the universe is made out of particles
5:24
Speaker 1: and bits of energy out there. But as it turns out,
5:27
Speaker 1: there are lots of different ways you can put together
5:29
Speaker 1: those bits of matter and energy and which gives you
5:31
Speaker 1: all kinds of different results, and there are people still
5:34
Speaker 1: figuring this out. You know, I'm a particle physicists. Of
5:36
Speaker 1: My natural inclination for understanding how the world works is
5:40
Speaker 1: to take it apart, is to reduce it to its smallest,
5:43
Speaker 1: most fundamental elements. But there are other people who work
5:46
Speaker 1: in a completely different direction. Their basic question is, how
5:49
Speaker 1: do we make some new kind of Goo? And can
5:52
Speaker 1: we make good that can do things that Goo never
5:54
Speaker 1: did before? They combine those fundamental pieces of the universe
5:58
Speaker 1: in new ways to try to make him dance and
6:01
Speaker 1: Jiggle and do things that no other kinds of Google
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Speaker 1: have done before. Yeah, because there are many different ways
6:06
Speaker 1: that matter can arrange itself. They're called states of matter. Right,
6:10
Speaker 1: there's liquid and gas and solids and plasma. Right that
6:14
Speaker 1: those are the states of matter that we know of.
6:16
Speaker 1: Those are the famous classical states of matter. But as
6:19
Speaker 1: we explore the universe and push on these things we
6:22
Speaker 1: discover the matter, can do all sorts of weird kinds
6:25
Speaker 1: of things. We talked on the podcast recently about Cork
6:28
Speaker 1: gluon plasma, or you called it Quasma, a great name,
6:32
Speaker 1: by the way. Yes, I'm still waiting for my noble price. Well,
6:35
Speaker 1: just keep eating Banasma as you wait. Yeah, yeah, that
6:38
Speaker 1: might slip with the Noble Price Committee, but it's amazing
6:42
Speaker 1: to me all the things that emerge in our universe.
6:45
Speaker 1: You know, one deep answer to the question what is
6:47
Speaker 1: the universe made out of is to reveal its fundamental bits.
6:50
Speaker 1: But I think it's equally important to understand what those
6:53
Speaker 1: bits do when they work together, because you can't explain
6:56
Speaker 1: the entire universe from the fundamental pieces. Even if you
6:59
Speaker 1: had a complete and unique string theory that described the
7:02
Speaker 1: fundamental theory of everything, you couldn't use it to predict
7:05
Speaker 1: hurricanes or traffic on the four oh five, because these
7:09
Speaker 1: are properties that emerge at a different scale. When you
7:11
Speaker 1: zoom out from the universe from this time, these little bits,
7:14
Speaker 1: you notice these incredible properties, places where we find these
7:18
Speaker 1: interesting and simple mathematical stories that we can tell about
7:21
Speaker 1: the universe, whether or not they are fundamental. Yeah, so
7:24
Speaker 1: there are these four basic states of matter that most
7:27
Speaker 1: people are familiar with, solid gas, liquid plasma, and we're,
7:30
Speaker 1: I guess they're popular and people know them because we
7:33
Speaker 1: see them in our everyday lives. Right. They're sort of
7:35
Speaker 1: what how matter usually sticks together. But, as you were saying,
7:38
Speaker 1: there are many other ways that matter can stick together
7:40
Speaker 1: if you go down into the weirder realm of quantum physics. Yeah,
7:45
Speaker 1: if you stick things together in weird ways and Zap
7:47
Speaker 1: them with lasers, you can find stuff that does things
7:50
Speaker 1: that no other kind of stuff can do. You've probably
7:53
Speaker 1: heard of Bose Einstein condensates, for example, weird collections of
7:58
Speaker 1: particles that act all together as a single quantum state,
8:02
Speaker 1: a macroscopic blob of stuff with quantum properties. That's another
8:06
Speaker 1: example of how you can squeeze and tweak matter into
8:09
Speaker 1: weird configurations to do new kinds of stuff and new
8:13
Speaker 1: kinds of stuff. Is What we'll be talking about here today.
8:16
Speaker 1: So to be on the PODCAST, we'll be asking the question.
8:23
Speaker 1: What are quantum glasses? Now, Daniel, I'm guessing these are
8:27
Speaker 1: not just things you wear to see quantum things better.
8:31
Speaker 1: When we go to a quantum physics conference, everybody puts
8:34
Speaker 1: these things on. It's not going to a three D movie, right.
8:37
Speaker 1: It's for cure and quantum myopia. Is that what it's
8:40
Speaker 1: there for? Or are they for drinking quantum wine or juice?
8:44
Speaker 1: Quantum juice? So you can say I'm not sure if
8:46
Speaker 1: I drink that glass of wine or if somebody else did,
8:49
Speaker 1: shrouding your drink my glass of wine, I meaning glasses
8:52
Speaker 1: of quantum. Have you drunk today? One and zero at
8:55
Speaker 1: the same time. There's a probability distribution that I'm drunk
9:00
Speaker 1: quantum glasses. So these are two words I'm familiar with,
9:02
Speaker 1: but I've never seen them together in the same phrase.
9:05
Speaker 1: These are really interesting kind of materials. Sometimes they're also
9:08
Speaker 1: called spin glasses, as we'll learn about later, because they
9:12
Speaker 1: involve quantum spin. So it's a really fun topic and
9:16
Speaker 1: something a bunch of listeners have been emailing me about
9:18
Speaker 1: because they saw articles about spin glasses and quantum glasses
9:22
Speaker 1: and they wanted to understand. Hey, what are these things anyway?
9:26
Speaker 1: Interesting and can you make a spin bottle out of glass?
9:29
Speaker 1: Is that the same thing? I think you're thinking of
9:31
Speaker 1: the game spin, the boss Spin right. Well, as usually,
9:35
Speaker 1: we were wondering how many people out there had heard
9:37
Speaker 1: of this phrase quantum glasses or had any idea of
9:40
Speaker 1: what they are. So thank you very much to those
9:42
Speaker 1: of you who are willing to answer these questions. It's
9:44
Speaker 1: really helpful to give us a sense for what people
9:47
Speaker 1: are thinking and what they already know. If you'd like
9:49
Speaker 1: to participate for future episodes, please don't be shy. Right
9:53
Speaker 1: to me two questions at Daniel and Jorge Dot Com
9:56
Speaker 1: and I'll set you up. So think about it for
9:57
Speaker 1: a second. What do you think quantum glass this are,
10:00
Speaker 1: and what could you see with them? Here's what to
10:02
Speaker 1: be glad to say. Quantum glasses, I guess, are not
10:06
Speaker 1: spectacles to view through, but they should be a kind
10:10
Speaker 1: of material. In material science, glasses are a class of
10:14
Speaker 1: materials that are characterized by being that it disorganized. So
10:19
Speaker 1: quantum glasses should be a quantum soup that is disorganized.
10:26
Speaker 1: I have no idea. I don't think they're the tiny
10:29
Speaker 1: little reading glasses that some people perched on the end
10:32
Speaker 1: of their nose, nor are they the tiny little shot
10:34
Speaker 1: glasses one might use for a very strong drink. Even
10:37
Speaker 1: those are not quite quantum level, and one should use
10:41
Speaker 1: distance glasses, if any, rather than reading glasses and not
10:44
Speaker 1: drink alcohol while driving a Volkswagen Quantum. So I'm going
10:49
Speaker 1: to take a wild guess that there's something that refocuses
10:53
Speaker 1: beams of quantum particles, much like how eyeglasses and other
10:57
Speaker 1: such lenses refocusames of light. I have absolutely no idea
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Speaker 1: what quantum glasses could be, so this is going to
11:05
Speaker 1: be a completely uneducated guest in every way. My mind
11:09
Speaker 1: originally went to glasses, like glasses who wear, but then
11:12
Speaker 1: I also thought of glasses as like a container for
11:15
Speaker 1: a liquid. So my guess is that it is some
11:18
Speaker 1: type of container through which we can better observe quantum events,
11:23
Speaker 1: events on a quantum scale. I think quantum glasses is
11:27
Speaker 1: a system physicists use two negotiate quantum theory. Either that
11:35
Speaker 1: or it's the glasses I used to use when I
11:39
Speaker 1: was a heavy drinker. But take a guess. Quantum glasses
11:44
Speaker 1: helps you see shrodingerl's cat, exactly what that cat is doing,
11:52
Speaker 1: and it's no whereabouts. If I was to reduce, I
11:55
Speaker 1: reckon it's some way of being able to utilize something
11:59
Speaker 1: to view or to assess the way the quantum world
12:03
Speaker 1: is behaving, similar to a spectacles on to say the world.
12:07
Speaker 1: I wonder if it's got something to do with our
12:09
Speaker 1: ability to say or interact with the quantum world. All Right,
12:13
Speaker 1: a lot of interesting ideas. I love the tiny little
12:16
Speaker 1: reading glasses. They're like little quantum particles you put in
12:21
Speaker 1: your eyeballs. Is that what they're saying? No, I'm imagining
12:24
Speaker 1: like literal tiny glasses perched at the very, very tip
12:27
Speaker 1: of my nose, and they're there and they're not there
12:30
Speaker 1: at the same time. But I'm most impressed with this
12:34
Speaker 1: one guest that says glasses are disorganized. So maybe quantum
12:38
Speaker 1: glasses are a disorganized quantum soup. That is so close
12:42
Speaker 1: to correct I'm amazed. Yeah, yeah, I feel like maybe
12:47
Speaker 1: they cheated or something that. I wonder if they read
12:49
Speaker 1: an article about this. I don't know the rules are.
12:51
Speaker 1: You're not allowed to Google. So, you know, maybe they
12:54
Speaker 1: just intuited it. Maybe this person just is a physics genius. Wow,
12:58
Speaker 1: maybe you should be hiring them, or maybe you already
13:01
Speaker 1: hird them. I don't know. Did you ask your Grad Students? Sometimes?
13:03
Speaker 1: I do sometimes, but these are all random Internet people,
13:06
Speaker 1: although you know, some of our listeners are physics Grad
13:09
Speaker 1: students and some of them aren't. So there's a pretty
13:12
Speaker 1: wide spectrum of backgrounds. Yes, in the end we're all
13:14
Speaker 1: random Internet people, Daniel, but anyways, lots of great ideas,
13:17
Speaker 1: and so let's dig into it. What is a quantum glass? Daniel,
13:21
Speaker 1: break it down for us. So, basically, our listener gave
13:23
Speaker 1: us the answer. A quantum glass is a material where
13:26
Speaker 1: the quantum states are disordered in a way that's similar
13:31
Speaker 1: to way like a window glass is a disordered solid
13:34
Speaker 1: rather than like an ordered crystal. You know. That means
13:37
Speaker 1: that things on the inside are not like arranged, so
13:40
Speaker 1: everything points in the same direction. It's sort of scrambled
13:43
Speaker 1: a little bit. MM interesting because I guess bits of matter,
13:48
Speaker 1: atoms and quantum particles, they have a specific direction, aren't
13:52
Speaker 1: they just like little blobs? They do have specific directions
13:55
Speaker 1: because they have quantum spins, right, and luxurns are not
13:58
Speaker 1: just tiny particles with charred gen mass. They also have
14:01
Speaker 1: other quantum properties, including this weird thing quantum spin, that
14:05
Speaker 1: we don't fundamentally know what it is. We don't think
14:08
Speaker 1: that these electrons are actually spinning because we think of
14:12
Speaker 1: them as point particles. And even if you account for
14:15
Speaker 1: the width of their wave function, if they were literally spinning,
14:18
Speaker 1: then their surfaces would have to go faster than the
14:21
Speaker 1: speed of light to explain all of this energy. It's
14:24
Speaker 1: some other weird property. We have a whole podcast episode
14:26
Speaker 1: about what is quantum spin. For today, all we need
14:29
Speaker 1: to know is that it can have a direction. Electron
14:32
Speaker 1: is gonna be like spin up or spin down, and
14:34
Speaker 1: this is true for other particles. Protons and neutrons and
14:38
Speaker 1: even for atoms, can have an overall spin. So that
14:41
Speaker 1: gives them a directionality. They're not just points, right. They
14:44
Speaker 1: have a property that somehow points in a certain specific
14:47
Speaker 1: direction in space. And you said it's just sort of
14:50
Speaker 1: like normal glass to like maybe let's start with that.
14:54
Speaker 1: What is a normal glass? Yeah, so a normal glass
14:57
Speaker 1: is something that feels solid. Like you go to Your
14:59
Speaker 1: Window Pane Ene and you touch it, it it feels solid, right.
15:02
Speaker 1: But most solids out there are not like glass. Most
15:05
Speaker 1: solids are ordered. They're organized like a crystal, you know.
15:08
Speaker 1: They're sort of like built out of a bunch of
15:10
Speaker 1: tiny bricks that are all stacked together very nicely and
15:13
Speaker 1: neatly into like a big cubic lattice. You can think
15:17
Speaker 1: of them as like a bunch of atoms where the
15:19
Speaker 1: atoms all line up in three directions. You know, if
15:22
Speaker 1: you like sort of looked down it, you could line
15:24
Speaker 1: up all the atoms sort of like in front of
15:26
Speaker 1: you and then along the surface and this kind of thing.
15:30
Speaker 1: So most stuff that's out there is fairly well organized,
15:33
Speaker 1: but a glass is not a glass. It's just sort
15:36
Speaker 1: of like a pile of stuff that's stuck together, but
15:39
Speaker 1: it's not well organized. What do you mean? Mean? Like,
15:41
Speaker 1: my wooden desk is neatly organized, but it looks pretty messy.
15:45
Speaker 1: Your wooden desk is even more complicated because it has
15:48
Speaker 1: all sorts of structure in the wood itself. But you know,
15:51
Speaker 1: if you take it like a block of ice, it's
15:52
Speaker 1: a single kind of stuff. It's cold and the atoms
15:55
Speaker 1: inside of it are arranged in a lattice. There's like
15:57
Speaker 1: the distance between two atoms is pretty much a single number,
16:01
Speaker 1: and that's true for most things like metals, et CETERA.
16:04
Speaker 1: But they're both solid, right, like a piece of glass
16:06
Speaker 1: is solid, just like a piece of ice is solid too.
16:09
Speaker 1: That's right. A piece of glass is solid because its
16:11
Speaker 1: volume doesn't change and it's shape doesn't change. The build
16:14
Speaker 1: just sit there, right. But if you zoomed in with
16:16
Speaker 1: a microscope, an amorphous solid like glass would look very
16:20
Speaker 1: different from a crystal solid, a crystal slid. You would
16:22
Speaker 1: zoom in and it would look like it's built out
16:24
Speaker 1: of these little pieces that are all arranged very nicely,
16:27
Speaker 1: like somebody stacked a bunch of legos together, whereas an
16:29
Speaker 1: amorphous solid would look like, you know, the inside of
16:32
Speaker 1: your Lego bin before you built something would be like
16:34
Speaker 1: a disorganized pile of stuff that's still somehow stuck together.
16:38
Speaker 1: And you know, glass is an example of it. And
16:40
Speaker 1: then we call these things glasses. But there are other examples,
16:44
Speaker 1: like a lot of plastics are like this, gels are
16:46
Speaker 1: like this. You know, sand is like this. If you
16:49
Speaker 1: zoom in close enough, it's not like stacked up in
16:51
Speaker 1: little bricks, it's just sort of like a big jumble.
16:54
Speaker 1: But you're right, it is solid. It manages to stick
16:56
Speaker 1: together well enough still have the properties of a solid, right,
17:00
Speaker 1: although I've heard glasses actually a liquid, like a really
17:03
Speaker 1: slow liquid, right, isn't it? That is something that is
17:05
Speaker 1: said often, but I don't think it's actually true. I
17:08
Speaker 1: think the people have been misled by old windows, for example,
17:12
Speaker 1: that are thicker on the bottom than on the top.
17:14
Speaker 1: That's mostly because of the glass making process at the time.
17:19
Speaker 1: Glass itself, I don't think, actually flows on a time
17:21
Speaker 1: scale that humans can measure, but on a long time
17:24
Speaker 1: scale it sort of does. Right technically, it's true that
17:26
Speaker 1: these things can flow on very, very long time scales,
17:30
Speaker 1: but most of the things where you see it's like
17:32
Speaker 1: thicker on the bottom than on the top is not
17:34
Speaker 1: because the glasses flowed. It's a little bit unclear exactly
17:37
Speaker 1: what the time scale is for glass to flow into
17:40
Speaker 1: a puddle, for example. It might be a very, very
17:42
Speaker 1: long time scale. Well, Um, I guess maybe a question
17:45
Speaker 1: I have is what's the difference between something that is
17:47
Speaker 1: a glass and something that is not a glass? Like
17:50
Speaker 1: what makes some materials arrange themselves into crystal structure, lattices,
17:55
Speaker 1: and what makes them just stick together morphously? The answer
17:58
Speaker 1: is that it is complicated. For some materials it depends
18:02
Speaker 1: on how they are cooled. So if you cool things really,
18:05
Speaker 1: really fast, they don't have a chance for the crystal
18:07
Speaker 1: to organize itself. Other materials just don't fall into a
18:10
Speaker 1: crystal because of the way their interactions work. They can't
18:14
Speaker 1: build a regular lattice it depends a lot on the
18:16
Speaker 1: exact material and also on how you get it to
18:19
Speaker 1: its state. So some things can be crystals or can
18:22
Speaker 1: be glasses, and it just depends on how quickly they
18:25
Speaker 1: are cooled down. Doesn't a lot of it also depend
18:28
Speaker 1: on like the structure of the molecules in the material?
18:31
Speaker 1: For example, you know, like maybe what I think, water
18:34
Speaker 1: falls into crystals because the two H and the o
18:37
Speaker 1: kind of form a kind of a weird shape and
18:39
Speaker 1: there there are only so many different ways you can
18:42
Speaker 1: kind of make those shapes stick together. Yeah, that's what
18:44
Speaker 1: I mean by the interactions of the materials. They imagine.
18:47
Speaker 1: For example, you have a weird shaped tile, a question
18:49
Speaker 1: you can ask is like can I tile this across
18:51
Speaker 1: the floor in a regular pattern? And that's basically what
18:54
Speaker 1: you're trying to do when you build a crystal is
18:56
Speaker 1: like fill up a space with a regular pattern with
18:58
Speaker 1: a weird shape that you have. So, as you say,
19:01
Speaker 1: for example, water has kind of a weird shape, but
19:03
Speaker 1: it's capable of building crystal. But actually it can build
19:05
Speaker 1: lots of different kinds of crystals based on the temperature
19:08
Speaker 1: and pressure of its formation. There's like ice four and
19:11
Speaker 1: ice six and ice. Nine. These are all different crystal
19:14
Speaker 1: arrangements of the same basic thing, based on the temperature
19:17
Speaker 1: and the pressure and the conditions in which it was formed.
19:20
Speaker 1: So it's a really complicated question. Yeah, and I think
19:22
Speaker 1: it also depends on like what makes the molecules stick
19:26
Speaker 1: together right like an h do. It could be the
19:29
Speaker 1: forces between the OHS, for example, what I'm just giving
19:32
Speaker 1: out random example, or it could be, you know, the
19:34
Speaker 1: forces between the H is and things like that, right exactly,
19:38
Speaker 1: and some parts of it are stickier than others, right,
19:40
Speaker 1: depending on the energy levels of their electrons. So it's
19:43
Speaker 1: something that's not always easy to predict. Sometimes the best
19:46
Speaker 1: way to figure it out is just to try. It's
19:48
Speaker 1: just to go out and see what happens. So we
19:51
Speaker 1: have people whose entire careers are just like mapping out
19:53
Speaker 1: the phase diagram of various kinds of materials, understanding what
19:57
Speaker 1: it does under certain configurations. Think maybe the takeaway is
20:01
Speaker 1: that stuff sticks together in general and there are there
20:04
Speaker 1: are many different ways for it to stick together and
20:06
Speaker 1: sometimes they stick together in regular patterns, like in a grid,
20:09
Speaker 1: and sometimes they just kind of bundle up like randomly, right,
20:12
Speaker 1: and that's what a class is and classes is an
20:16
Speaker 1: example of this category. You also have like plastics and
20:18
Speaker 1: polymers and Thoms and gels. These all follow the same
20:22
Speaker 1: kind of structure as glasses. They are amorphous rather than crystalline, right,
20:26
Speaker 1: and those are the in the macro scale there are
20:29
Speaker 1: morphous materials, kind of like the atom level, right. We're
20:32
Speaker 1: not yet at the quantum level. Yeah, these are things
20:34
Speaker 1: at the atom level exactly. So then you're saying a
20:37
Speaker 1: quantum glass is a material in which stuff is stuck together,
20:42
Speaker 1: but Um, it's a morphous in its quantum states. Yeah,
20:45
Speaker 1: and I predict you're gonna be pretty unhappy with this
20:47
Speaker 1: distinction about what's a quantum state or not, because in
20:50
Speaker 1: the end all of these interactions are quantum, like when
20:53
Speaker 1: two water molecules touch each other and form part of
20:56
Speaker 1: a crystal. That is a quantum interaction between quantum particle.
21:00
Speaker 1: But when we talk about quantum glasses, we mean that
21:02
Speaker 1: we're adding a new dimension to it, that we're considering
21:05
Speaker 1: another quantum property, in this case quantum spin, because we're
21:09
Speaker 1: not interested in how the objects ordered themselves in space.
21:12
Speaker 1: We're interested in the distribution of these spins. Are the
21:15
Speaker 1: spins ordered or are the spins disordered. Well, I guess
21:19
Speaker 1: maybe a distinction is that like, for example, for Water
21:22
Speaker 1: and ice? I mean you're talking about atoms being in
21:24
Speaker 1: a kind of a lattice, right, and atoms themselves don't
21:27
Speaker 1: have spin, or you know, don't. Isn't it like the
21:30
Speaker 1: electrons and the atoms and the corks and the atoms
21:32
Speaker 1: that have spin, not the atom itself? The atoms themselves
21:35
Speaker 1: do have an overall spin. It comes from adding up
21:37
Speaker 1: the spin of all the bits, the nuclear spin, the
21:39
Speaker 1: electron spin, and that's what's important for forming magnets, for example,
21:43
Speaker 1: is the spin of the whole atom. It adds up.
21:45
Speaker 1: So we do think about the spin of the atom itself,
21:48
Speaker 1: not just the electrons inside of it. All right, well,
21:51
Speaker 1: let's get more into it and explain what exactly is
21:54
Speaker 1: a quantum glass and whether or not we've actually seen
21:56
Speaker 1: them and can touch them and maybe use them to
21:59
Speaker 1: read quantum books. So let's get into that, but first
22:02
Speaker 1: let's take a quick break. All right, we're talking about
22:16
Speaker 1: quantum glasses. Are these like x Ray glasses that let
22:20
Speaker 1: me see through things? They'll let you see immediately to
22:23
Speaker 1: the next big discovery in physics. I wish isn't I
22:29
Speaker 1: just called working. What if I could just put on
22:34
Speaker 1: quantum glasses and look at my calendar and be like
22:36
Speaker 1: that's the day you're gonna make a big discovery, what
22:39
Speaker 1: would you do? Would you work harder or less if
22:42
Speaker 1: you need you're gonna make a big discovery next week. Well,
22:45
Speaker 1: I know that napping is a crucial part of making
22:47
Speaker 1: big discovery, so make sure to get that out of
22:49
Speaker 1: the way first. Right, right, but would you have more
22:51
Speaker 1: or less if you knew your feature? Well, future Daniel
22:54
Speaker 1: would have already have seen his future using quantum glasses,
22:57
Speaker 1: so that would be accounted for, sort of like Harry
23:00
Speaker 1: Potter time travel. Right, right, I guess that you're saying
23:02
Speaker 1: you don't have any free will. That's right, I'm completely
23:05
Speaker 1: determined by my calendar. I just do whatever it says.
23:08
Speaker 1: That's right. Your naps are determined by your future self.
23:11
Speaker 1: It's not your fault. If I put make huge discovering
23:14
Speaker 1: to the calendar, then I have no choice. I have
23:16
Speaker 1: to make a huge discovery that day. Right. Yeah, that's
23:18
Speaker 1: what I'm saying, but I'm saying like, how would it
23:20
Speaker 1: affect your presence choices? I would type that into my calendar.
23:23
Speaker 1: A lot of times. But anyways, we're talking about quantum
23:25
Speaker 1: glasses and what they are, and we talked about how
23:28
Speaker 1: a glass is a material in which all of the
23:30
Speaker 1: bits in it are kind of disordered, amorphous, not in
23:34
Speaker 1: any kind of grid or structure, and the same can
23:37
Speaker 1: be said for quantum materials. That's right. And traditionally, when
23:41
Speaker 1: we talk about glasses we talk about disorder in the
23:43
Speaker 1: location of the atoms, so if you zoomed in with
23:46
Speaker 1: a microscope you would see like a big pile of
23:48
Speaker 1: stuff rather than a nice, crisp, organized lattice. And now
23:51
Speaker 1: we're talking about something else. We're talking about quantum properties
23:54
Speaker 1: of these objects. So you can have something which is
23:56
Speaker 1: a nice organized lattice in space, like a grid of
24:00
Speaker 1: atoms that are perfectly organized, but it can be a
24:03
Speaker 1: quantum glass if their quantum properties are disorganized, if their spin,
24:08
Speaker 1: for example, so their magnetic moment is not organized in
24:12
Speaker 1: a very nice way. WHOA. So it's almost like something
24:16
Speaker 1: you layer on top of other materials. This idea. It's like,
24:19
Speaker 1: you know, we have this traditional distinction between glasses and crystals,
24:23
Speaker 1: but that is sort of irrelevant here. Right what counts
24:26
Speaker 1: is whether or not the quantum states are aligned in
24:29
Speaker 1: a pattern or not. Exactly whether it's a quantum glass
24:32
Speaker 1: depends on its quantum states, not the spatial locations. And
24:36
Speaker 1: here mostly we're talking about things which are physical crystals.
24:39
Speaker 1: You know, their atoms are nicely arranged in a grid,
24:43
Speaker 1: but the quantum states of those atoms in the grid
24:46
Speaker 1: are sort of scrambled. And you know traditionally if you
24:48
Speaker 1: have stuff in a grid, the magnetic fields can be
24:51
Speaker 1: nicely aligned. So the ferro magnets, for example, is something
24:54
Speaker 1: where all the atoms have their spins in the same direction,
24:57
Speaker 1: which is what controls their little magnetic moments and all
25:00
Speaker 1: adds up to be a big magnet. So if you
25:02
Speaker 1: have a fridge magnet for example, like a nice piece
25:04
Speaker 1: of iron that's been magnetized, has all of its spins
25:07
Speaker 1: in the same direction, they all add up together they
25:10
Speaker 1: make like a permanent magnet. That's a ferro magnet. That's
25:13
Speaker 1: not a quantum glass because the spins are all nicely
25:16
Speaker 1: organized nicely right. That's what a magnet is. Right. Our
25:20
Speaker 1: magnet is usually metal crystal where all of the atoms
25:24
Speaker 1: in it have the same spin direction, which kind of like,
25:28
Speaker 1: I guess, synchronizes them. And makes them add up to
25:30
Speaker 1: a giant kind of spin or magnetic pole. Right. And
25:33
Speaker 1: one reason that's possible is because the spins like to
25:37
Speaker 1: align with each other. In a ferromagnetic material, that's the
25:40
Speaker 1: relaxed state, that's the lowest energy states, when the spins
25:44
Speaker 1: are pointing in the same direction. It likes to be
25:46
Speaker 1: that way. There are other kinds of material, like anti ferromagnets,
25:49
Speaker 1: where they prefer the spins to be the opposite directions,
25:53
Speaker 1: where you want your neighbor to have the opposite spin
25:55
Speaker 1: is you, and because of the way these molecules interact
25:58
Speaker 1: in their funny shapes and all of their forces between them,
26:01
Speaker 1: that happens to be the lowest energy state. That's the
26:04
Speaker 1: opposite anti ferromagnet where you have a crystal, but it's
26:07
Speaker 1: like spin up, down, up, down, up, down, up, down.
26:10
Speaker 1: Both of these are examples of well organized magnetic lattices. Interesting.
26:15
Speaker 1: And does that apply only to metals, like magnet metals?
26:18
Speaker 1: Like can I take a block of ice and align
26:21
Speaker 1: all of the magnetic spins in the atoms of water
26:25
Speaker 1: in a block of ice to make it magnetic? You
26:27
Speaker 1: can't do that with a block of ice. Now, a
26:29
Speaker 1: block of ice is not ferromagnetic and it's also not paramagnetic.
26:34
Speaker 1: paramagnetic ar materials that are sort of weakly magnetic and
26:37
Speaker 1: if you put them in a magnetic field they will
26:40
Speaker 1: eventually align, but then when you take the magnetic field
26:42
Speaker 1: away they might lose it. But ice is neither of those.
26:45
Speaker 1: Why not? Why can't I just, you know, somehow arrange
26:48
Speaker 1: my water molecule so that all the spins are aligned?
26:51
Speaker 1: It depends on how the bits of the atom are organized.
26:55
Speaker 1: So it depends sort of like on the overall spin
26:57
Speaker 1: of the atom. We were talking earlier about having spins
27:00
Speaker 1: on the electrons and spins on the Nuclei. If those
27:03
Speaker 1: sort of all add up to an overall small amount
27:06
Speaker 1: of spin, then there's not really much to play with there.
27:09
Speaker 1: But if they come together in a way that makes
27:11
Speaker 1: like a large magnetic dipole for the individual atom, then
27:15
Speaker 1: you have spins that can get aligned, and so that's
27:17
Speaker 1: what sort of what's different between some materials which are
27:20
Speaker 1: like ferromagnetic because they can be aligned, and other materials
27:23
Speaker 1: that are not. M You're saying like in something like
27:26
Speaker 1: a water atom or molecule, all of the electrons and
27:28
Speaker 1: all the corks in it are not easily or readily aligned.
27:32
Speaker 1: They like to kind of being random positions, which sort
27:35
Speaker 1: of castles. There's spin out. Yeah, and some of these materials,
27:39
Speaker 1: for example, the electrons want to be opposite spins so
27:42
Speaker 1: that they cancel out, and other materials they're set up
27:44
Speaker 1: in a way that electrons can all be in the
27:46
Speaker 1: same spins. You have an overall spin to the atom
27:49
Speaker 1: M and so that's the difference between a material that
27:52
Speaker 1: can form a magnet and one that cannot. That's one
27:54
Speaker 1: of the differences. This whole thing is very complicated. It's
27:57
Speaker 1: difficult to make like broad generalizations, but that's sort of
28:00
Speaker 1: like the cartoon picture. Why some things can be magnetic
28:03
Speaker 1: and some things cannot. All right, so maybe tell me
28:05
Speaker 1: more about these anti ferromagnetic materials. So the anti ferromagnetic
28:10
Speaker 1: materials are the ones where they like to be opposite,
28:12
Speaker 1: where every neighbor prefers to be the opposite of the other,
28:15
Speaker 1: and it just depends on their interactions. Whether that's the
28:17
Speaker 1: lowest energy states, so they like to be up against
28:20
Speaker 1: each other or whether they like to be aligned with
28:22
Speaker 1: each other. They like to be aligned with each other.
28:24
Speaker 1: It's a ferromagnet. They like to be opposite with each other.
28:26
Speaker 1: It's an anti ferromagnet imagine like a big sheet of
28:29
Speaker 1: these atoms. If you want them to be all aligned,
28:32
Speaker 1: there's an easy way to do that. You spin them
28:34
Speaker 1: all up or spin them all down. Right, you want
28:36
Speaker 1: them to be all anti line, there's still a pretty
28:39
Speaker 1: easy way to do that. On a square lattice, like
28:41
Speaker 1: every other one is up and every other one is down.
28:44
Speaker 1: So up, down, up, down, up, down. And you can
28:46
Speaker 1: imagine covering an entire plane or even a three d grid,
28:50
Speaker 1: where every atom's neighbor has the opposite spin as it
28:53
Speaker 1: does right. So if you're up, then you see down
28:56
Speaker 1: everywhere around you in the Lattice, and if you're down,
28:58
Speaker 1: you see up everywhere around to do in the lattice.
29:01
Speaker 1: So there's a way there to make an overall relaxation
29:05
Speaker 1: where everybody's in their lowest state and everybody's happy. I
29:08
Speaker 1: guess I got a little confused because I think basically,
29:10
Speaker 1: like all materials, is kind of a quantum glass, right,
29:13
Speaker 1: like isis sort of a quantum glass because it's quantum
29:16
Speaker 1: spins are in all kinds of directions. Right, like my
29:19
Speaker 1: hand is a quantum glass in that sense of the
29:22
Speaker 1: definition of it, I suppose. So ice and an example,
29:24
Speaker 1: has sort of negligible quantum spins compared to the kind
29:27
Speaker 1: of things we're talking about here. So it's not really
29:29
Speaker 1: in the category of things that we're discussing. We're talking
29:31
Speaker 1: about materials that do have quantum spins. Do they like
29:35
Speaker 1: to be aligned or do they like to be anti aligned?
29:37
Speaker 1: And can you make the material in such a way
29:40
Speaker 1: that the whole thing is happy overall? The whole thing
29:43
Speaker 1: is relaxed into its lowest energy state, either inferro magnets,
29:46
Speaker 1: by lining up all the spins or anti ferro magnets
29:49
Speaker 1: by flipping all of the spins right. But I think
29:52
Speaker 1: you're talking now about like let's post a little challenge
29:55
Speaker 1: for ourselves. Let's let's see if we can find material
29:58
Speaker 1: that you can arrange in a crystal, in the lattice
30:00
Speaker 1: in like a grid, but somehow also make all these
30:04
Speaker 1: spins differently or randomly directed. Yeah, so a spin glass
30:08
Speaker 1: is a kind of material where the spins can't all relax,
30:11
Speaker 1: when you can't find a configuration where everybody's happy. We
30:16
Speaker 1: talked a minute ago about anti ferromagnets, where things like
30:19
Speaker 1: to be the opposite spin of their neighbor. And that
30:21
Speaker 1: works in a square lattice right, where you have like
30:24
Speaker 1: a neighbor to both sides and above you and behind
30:27
Speaker 1: you and in front of you. What if, for example,
30:29
Speaker 1: you have like a triangular lattice instead of a square lattice,
30:32
Speaker 1: and so you have like two neighbors? Imagine just points
30:35
Speaker 1: on a triangle. You Label one point up, the next
30:37
Speaker 1: one down. What's the third point going to be? It
30:40
Speaker 1: wants to be down because has one up neighbor and
30:42
Speaker 1: it wants to be up because it has one down neighbor.
30:45
Speaker 1: So it doesn't know where to go right. It can't
30:47
Speaker 1: satisfy both of its neighbors at the same time. Well,
30:50
Speaker 1: you're saying, I guess that these anti ferromagnetic I guess
30:52
Speaker 1: atoms or molecules. They're sort of like contrarians, like if
30:56
Speaker 1: their neighbor is up, they want to go down right
30:59
Speaker 1: and if they have two neighbors that are up, then
31:01
Speaker 1: they want to go down. I guess two questions. First
31:03
Speaker 1: of all, why are they so continuing? Hey, some people
31:07
Speaker 1: just can be grumpy and you shouldn't ask too many questions.
31:09
Speaker 1: You know, it depends on the complicated interactions between the atoms.
31:13
Speaker 1: Atoms are not simple objects. Have a spatial extent and
31:15
Speaker 1: they're slashing around. They have all their internal forces. You're
31:19
Speaker 1: closer to some bits of it than other bits of it,
31:21
Speaker 1: and the spins of these objects interact right and some
31:24
Speaker 1: of them like to be spin up and some of
31:26
Speaker 1: them like to be spinned down. I guess the short
31:28
Speaker 1: answer is that it's really complicated and sometimes it even
31:30
Speaker 1: depends on distance. Like if you're close up, then they
31:34
Speaker 1: like to have the same spin and as you get
31:36
Speaker 1: further away, they like to have the opposite spin, and
31:38
Speaker 1: then as you gave them further away, they like to
31:40
Speaker 1: be the same spin again. It's really complicated and depends
31:43
Speaker 1: on a lot of the details of that exactly. The
31:46
Speaker 1: internal arrangements of each atom or molecule, I see. But
31:49
Speaker 1: is it, I guess, kind of like a magnet, right,
31:51
Speaker 1: like if I have two magnets and they're both, you know,
31:53
Speaker 1: have the same North Pole pointed in the same direction,
31:56
Speaker 1: like bring them together, like one of them will want
31:58
Speaker 1: to flip over so that it's opposite the other one.
32:01
Speaker 1: Is that kind of like the good analogy, or maybe
32:03
Speaker 1: even the same thing? That's the same thing for the
32:05
Speaker 1: Anti Ferro magnets right, except here we're talking about spins,
32:08
Speaker 1: but it's very similar. You know, the minimum energy state
32:11
Speaker 1: there is for one North Pole to be aligned with
32:13
Speaker 1: the other magnets South Pole, and if you try to
32:16
Speaker 1: push in the other direction, it's going to take some
32:18
Speaker 1: energy to keep it there and if you let go
32:20
Speaker 1: it will relax into the configuration where they have the
32:23
Speaker 1: opposite directions, where the North Pole and one magnet is
32:26
Speaker 1: aligned with the South Pole of other magnets. Okay, so
32:28
Speaker 1: now I think what you're saying is, you know, we
32:30
Speaker 1: have these materials, these atoms, that are contrarian. They like
32:32
Speaker 1: to be opposite the spin of the its neighbors. So
32:35
Speaker 1: now what happens? And if I put two up spins
32:38
Speaker 1: next to it, it's gonna want to be down spin.
32:40
Speaker 1: But what happens if I put an upspin and a
32:42
Speaker 1: down spin next to it? It gets you a little confused, right,
32:45
Speaker 1: or frustrated? Yeah, exactly, and that's what physicists call it.
32:47
Speaker 1: They call it a frustration when you can't arrange the
32:50
Speaker 1: spins in a way so the whole thing has minimum
32:53
Speaker 1: energy right in a square lattice. Imagine four points on
32:56
Speaker 1: a square could have like the top left to be up,
32:58
Speaker 1: on the bottom right be up and the other two
33:01
Speaker 1: points be down and everybody's happy because all the downs
33:03
Speaker 1: have only up neighbors and all the ups have only
33:06
Speaker 1: down neighbors. But in a triangular lattice you can't do that. Right.
33:09
Speaker 1: The third point has one up neighbor and one down
33:12
Speaker 1: neighbor and it can't decide which way to go. There's
33:15
Speaker 1: two possible states there that have the same energy and
33:18
Speaker 1: neither of them are like the minimum energy right. It's
33:20
Speaker 1: like having a conversation between three people and one of
33:22
Speaker 1: them is the contrarian. What happens that? When are the
33:24
Speaker 1: other people agrees with them, but the only one does not?
33:27
Speaker 1: What does the contrarian do? Exactly who to disagree with?
33:32
Speaker 1: And so this is what a spin glass is, because
33:35
Speaker 1: the spins end up sort of like disorganized. It's not
33:38
Speaker 1: like a Pharo magnet where they're all pointing in the
33:39
Speaker 1: same way, or an anti Faro Mac in a square
33:42
Speaker 1: crystal where they're all pointing opposite directions. It's kind of
33:45
Speaker 1: a disaster, right. So like tense, it's frustrated, it can't
33:49
Speaker 1: quite relax, and so where the spins end up is
33:52
Speaker 1: a little bit random. Interesting. So you're saying the part
33:56
Speaker 1: of the definition of what a quantum glass is is
33:59
Speaker 1: that kind of frust rate Shan built it into it.
34:01
Speaker 1: Like if I build the lattice with contrarian atoms and
34:04
Speaker 1: everyone's contrary to their neighbor, then it's and everyone's happy.
34:08
Speaker 1: Then that's not a quantum glass. Right, exactly. That's just
34:10
Speaker 1: a normal anti ferromagnetic crystal. But if you can somehow
34:14
Speaker 1: frustrate the atoms, then you have a quantum glass, because
34:17
Speaker 1: I guess everyone's frustrated and what constantly flipping back and forth?
34:22
Speaker 1: Is that kind of what happens? Yeah, everyone's frustrated, it
34:24
Speaker 1: can't find the minimum and it has new weird properties.
34:28
Speaker 1: So when we talk about a phase transition, there has
34:29
Speaker 1: to be like a change and how the material operates
34:32
Speaker 1: in one of its properties. Right, we don't say that
34:35
Speaker 1: cold water and hot water are different phases, even though
34:38
Speaker 1: they are chemically different, because there's no like large change
34:41
Speaker 1: in its macroscopic behavior. So for years or even decades,
34:44
Speaker 1: there was an argument about whether spin glasses really are
34:47
Speaker 1: their own phase of matter. And the people who say
34:50
Speaker 1: that it is its own phase of matter. They argue
34:52
Speaker 1: that it's unique because it has weird relaxation times. Like
34:56
Speaker 1: if you take a ferromagnet or an anti ferromagnet and
34:59
Speaker 1: you apply really strong magnetic field and you sort of
35:01
Speaker 1: mess up the spins, it will relax pretty quickly when
35:04
Speaker 1: you take away the magnetic field. But a spin glass,
35:07
Speaker 1: if you do that, it will react really differently. It
35:09
Speaker 1: will take like forever to relax and it will never
35:12
Speaker 1: come back to its original position. So people argue that
35:15
Speaker 1: that's enough of a different macro's copic property to be
35:18
Speaker 1: its own kind of thing. What do you mean? It
35:21
Speaker 1: takes a while, like the items keep switching back and
35:23
Speaker 1: forth or what? There's like turmoil inside of the material. Yeah,
35:27
Speaker 1: they have like decision paralysis. You know, it's like if
35:30
Speaker 1: you go to the cookie aisle and there's like a
35:33
Speaker 1: thousand cookies and your shopping list just says cookie. You're like, Oh,
35:37
Speaker 1: do I get Oreos? Do I get chips of oil?
35:39
Speaker 1: Look at those fudge ones. Oh No, I can't decide
35:41
Speaker 1: what I want and they all seem equally good. You
35:44
Speaker 1: could spend hours there wandering around switching, you know, taking
35:47
Speaker 1: stuff in and out of your basket, not sure what
35:49
Speaker 1: to actually buy, and so spin glasses are sort of
35:52
Speaker 1: like this. If you perturb them, you give them magnetic energy,
35:55
Speaker 1: you put them in the magnetic field and then you
35:56
Speaker 1: take it away, they take a long time sort of
35:59
Speaker 1: slashing back and forth spins, flipping and then flipping other spins.
36:02
Speaker 1: They can't find a comfortable situation to relax in M
36:06
Speaker 1: but I guess it isn't spin a quantum property, meaning
36:09
Speaker 1: like each atom has a spin that's both up and down,
36:13
Speaker 1: like they went in a particular direction? Wouldn't that sort
36:15
Speaker 1: of collapse the wave function of that quantum state? Yeah,
36:18
Speaker 1: really interesting question. It's true that spin is a quantum property,
36:22
Speaker 1: which means both that it can either be up or down,
36:24
Speaker 1: but not like in between. Right when you measure these
36:26
Speaker 1: things either get up or down, but it means that
36:30
Speaker 1: until you measure it, it's not necessarily determined. So what
36:33
Speaker 1: that means is that the whole thing has like a
36:35
Speaker 1: few different quantum states that are all possible. We're talking
36:38
Speaker 1: about is what happens when you measure it right. So
36:40
Speaker 1: you probe this thing. You ask like what's the spin
36:42
Speaker 1: over here? What's the spin over here? What's the spin
36:44
Speaker 1: over here? And you're right, that will collapse the wave
36:46
Speaker 1: function so that everybody's going to make a decision, but
36:48
Speaker 1: you come back another minute later and it's made a
36:50
Speaker 1: different decision. You come back another minute later it's made
36:53
Speaker 1: another decision. So you never really see it settle and
36:55
Speaker 1: relax into a fixed state. Right. So when you're talking
36:58
Speaker 1: about like this termoil, all the all the contrarians can
37:02
Speaker 1: not being able to decide which way they're being contrring about.
37:05
Speaker 1: It's more of like a quantum turmol right, like it's
37:07
Speaker 1: not actually flipping back and forth and it's not like
37:10
Speaker 1: you're at the cookie as'le trying to decide. It's like
37:13
Speaker 1: you're sort of in this state where you're you're decided
37:15
Speaker 1: and not decided. No, I think it really is decided
37:18
Speaker 1: or not decided. I mean you can take pictures of
37:20
Speaker 1: these things essentially using like skinning, tunneling, microscopy or otherways
37:24
Speaker 1: to probe the magnetic field. So you can collapse these
37:27
Speaker 1: wave functions and you can see them evolve over time.
37:29
Speaker 1: So you can see these things really are flipping or
37:32
Speaker 1: it's not like once you've collapsed the way function, then
37:34
Speaker 1: it's happy and it's going to stay there. You can
37:37
Speaker 1: collapse the way function, you can come back and collapse
37:39
Speaker 1: it again and then again and again, you can see
37:41
Speaker 1: that they're flipping their spins. So that's the interesting property
37:44
Speaker 1: about spin glasses is that they have these really long
37:47
Speaker 1: relaxation times. They're basically never in equilibrium. You know, another
37:51
Speaker 1: way to think about it is like say you sit
37:53
Speaker 1: down at a really long banquet table and there's silvil
37:56
Speaker 1: ware to your left and to your right. Do you
37:58
Speaker 1: take the one to your left or do you take
38:00
Speaker 1: the one to your right? You know, if everybody takes
38:02
Speaker 1: through to the left, everybody is happy. If everybody takes
38:04
Speaker 1: their right, everybody's happy. People are arguing. You know, no,
38:07
Speaker 1: that one's mine, that one's mine. Then you know you
38:09
Speaker 1: can't really settle into a comfortable state. So spin glasses
38:13
Speaker 1: are situations where, like, people can't agree about what the
38:15
Speaker 1: rules are and so everybody's just taking whatever silverware. Well then,
38:20
Speaker 1: you say, eventually it settles down. And so what is
38:23
Speaker 1: it settled down into? Salad forks or main course for
38:27
Speaker 1: that's the interesting thing about spin glasses is that it's
38:29
Speaker 1: very hard to predict. You know, when we try to
38:32
Speaker 1: understand the macroscopic properties of these things, we do so
38:35
Speaker 1: by starting from the microscopic we say, okay, crystal is
38:39
Speaker 1: made of these little bits, and then we expand our
38:41
Speaker 1: understanding from that basis, stacking them together to make the
38:44
Speaker 1: macroscopic properties. That's really hard to do with spin glasses
38:48
Speaker 1: because they're so crazy and unpredictable. They're basically never in equilibrium.
38:53
Speaker 1: So a lot of the mathematical tricks that we use
38:55
Speaker 1: to understand crystals don't really work for spin glasses, which
38:59
Speaker 1: lad to like invention of whole new categories of mathematics.
39:03
Speaker 1: M interesting. All right. Well, let's get into those new
39:07
Speaker 1: categories of maths and what these materials are good for
39:10
Speaker 1: and what we can learn from them. But first let's
39:13
Speaker 1: take another quick break. All right, we're talking about quantum glasses,
39:29
Speaker 1: which is one of our listeners said, is where you
39:31
Speaker 1: take shots of quantum whiskey or Tequila, one electron at
39:36
Speaker 1: a time. Man, it's quantized. I'll take forever to get drunk. Danny.
39:44
Speaker 1: That's the point, man, moderation in all things. Let See,
39:47
Speaker 1: one atom at a time. Alright. So it sounds like
39:50
Speaker 1: there are materials you can put together in a crystal
39:53
Speaker 1: that are unhappy basically at their core, because all of
39:56
Speaker 1: the atoms can't find a good arrangement of their want
40:00
Speaker 1: them spin the everyone is sort of in this state
40:03
Speaker 1: where they don't know whether to go up or down
40:04
Speaker 1: in their spin, and so you create a material with
40:06
Speaker 1: a lot of frustration in it exactly. And a lot
40:10
Speaker 1: of these spin glasses are not just like one kind
40:12
Speaker 1: of material and a lattice where they're all contrarians and
40:15
Speaker 1: it's arranged in a way where they can't be happy.
40:16
Speaker 1: A lot of the Times it's a few examples of
40:19
Speaker 1: something that is magnetic inside a larger crystal. So you'll
40:23
Speaker 1: have like a non magnetic material like gold or silver copper,
40:27
Speaker 1: and you sprinkle into it a few percent of magnetic atoms,
40:31
Speaker 1: iron or something else, and because of their interactions depend
40:34
Speaker 1: on the distance, whether they like they have the same
40:36
Speaker 1: spin or the opposite spin depends on how far apart
40:38
Speaker 1: they are. You can end up with these disordered spins.
40:41
Speaker 1: You're saying. That's how you make a quantum glass. You
40:44
Speaker 1: embed magnetic atoms into a regular metal exactly, and then
40:48
Speaker 1: you cool it down and you see, like how are
40:50
Speaker 1: they frozen in interesting you like you bake in the
40:54
Speaker 1: frustration of the magnetic atoms. You freeze it in. Yeah, exactly.
40:58
Speaker 1: All right. Well, I guess a good question for me
41:00
Speaker 1: is what are these materials good for or why are
41:03
Speaker 1: we interested in them? So these things don't have like
41:06
Speaker 1: an immediate practical application, if not, like with spin glasses,
41:10
Speaker 1: you can make quantum computers or you can build a
41:13
Speaker 1: better transistor or you can take tiny shots of hot
41:16
Speaker 1: cocoa or something like that. There's no immediate application, but
41:19
Speaker 1: it's an interesting and tricky problem and so people have
41:23
Speaker 1: been thinking about it and, you know, sweating over it
41:25
Speaker 1: and trying to figure out like can we describe these
41:28
Speaker 1: things mathematically? Is there some way to figure this out?
41:31
Speaker 1: To me, this is one of the deep questions of
41:33
Speaker 1: physics itself, you know, because again, since we don't have
41:36
Speaker 1: the fundamental theory of everything, all of the theories that
41:38
Speaker 1: we develop are what we call effective theories. They're like
41:42
Speaker 1: mathematical stories that we tell that describe the things that
41:46
Speaker 1: we see, but they're not like written into the fundamental
41:49
Speaker 1: firmament of the universe. You know, aliens, for example, might
41:53
Speaker 1: not come up with these same effective theories. They're just
41:55
Speaker 1: sort of useful descriptions, but it's incredible we can find them,
41:58
Speaker 1: but sometimes they're harder to find than others. You know,
42:01
Speaker 1: for Solids and for liquids we have found mathematical descriptions
42:04
Speaker 1: that are useful. For Spin glasses, it's been much, much
42:07
Speaker 1: harder because their interactions are more complicated and less regular,
42:12
Speaker 1: but it's inspired people to come up with all sorts
42:14
Speaker 1: of new mathematical tricks, one of which people think is
42:17
Speaker 1: the reason why we discovered the Higgs Boson. I guess
42:20
Speaker 1: maybe a step us through that a little bit more.
42:23
Speaker 1: What does that mean? Like we have an effective theory
42:25
Speaker 1: to describe like a regular magnet. Is that what you're saying?
42:27
Speaker 1: We have like a mathematical way to study the model
42:30
Speaker 1: how regular magnet works, but you're saying we don't have
42:33
Speaker 1: one yet for these crazy, frustrated materials. We've been working
42:37
Speaker 1: on we've been making progress. I mean by we I
42:39
Speaker 1: mean all the other physicists. We're not goofing off making podcasts. We,
42:43
Speaker 1: you know, as the general group of humans thinking about
42:46
Speaker 1: these kinds of things, have been working on this for
42:48
Speaker 1: a long time and I think it's always interesting when
42:50
Speaker 1: it requires a new kind of math. And so there's
42:53
Speaker 1: an Italian physicist Parisi who won the Nobel Prize for
42:56
Speaker 1: this in twenty one, because he came up with a
42:59
Speaker 1: new sort of math, thematical strategy for dealing with this complication.
43:03
Speaker 1: You know, one of the real problems is that these
43:05
Speaker 1: things can arrange themselves in lots of different ways and
43:09
Speaker 1: when you poke them, you know, you give them a
43:10
Speaker 1: little bit more magnetic energy. So you scramble all the
43:13
Speaker 1: spins and you watch them relax. You wonder, like why
43:16
Speaker 1: does it land in this configuration and not that one?
43:18
Speaker 1: Can we predict this kind of thing? Can we come
43:20
Speaker 1: up with some sort of mathematical way to grapple with
43:23
Speaker 1: this and predict what's going to happen? You can't be
43:26
Speaker 1: completely random. And I guess what do you mean by
43:28
Speaker 1: a new kind of math, like a new kind of
43:30
Speaker 1: like adding quantum to old math, or what does that mean?
43:33
Speaker 1: The Way Mathematics bakes progress is that sometimes they need
43:36
Speaker 1: to develop like a new kind of tool, you know,
43:38
Speaker 1: like they find differential equations and here's strategies for solving
43:42
Speaker 1: that kind of problem, or here's Algebra, you know, like
43:44
Speaker 1: the people who figured out how to write equations down
43:47
Speaker 1: and solve them to get understanding. We're able to solve
43:50
Speaker 1: certain problems that other people couldn't. And, for example, descartes
43:53
Speaker 1: made a lot of advances in geometry because he would
43:56
Speaker 1: able to figure out how to use Algebra to tackle geometry.
43:59
Speaker 1: Like if you could write down the equation of a circle,
44:02
Speaker 1: then you could solve systems of equations and understand geometric patterns.
44:06
Speaker 1: So here they've done something similar. They've invented to like
44:09
Speaker 1: new mathematical tools, and these mathematical tools are really thinking
44:13
Speaker 1: about the symmetry of the problem. Like you have this huge,
44:16
Speaker 1: complex tree of options that a spin glass can do.
44:20
Speaker 1: We can splip this way, you can flip that way,
44:21
Speaker 1: you can flip the other way. So what Paris he
44:23
Speaker 1: did was come up with a way to think about
44:25
Speaker 1: this in sort of the larger context, like don't just
44:28
Speaker 1: think about the one spin glass you have, think about
44:31
Speaker 1: all the other spin glasses and you don't have like
44:33
Speaker 1: replicas of that system and try to organize them into
44:37
Speaker 1: like branches. So like, Oh, these guys are all similar
44:39
Speaker 1: in this way, those guys are all similar in these
44:42
Speaker 1: other way. Think about like the choices that were made
44:44
Speaker 1: to get to this spin glass from the higher energy
44:48
Speaker 1: spin glass, and he found these ways to like organize
44:51
Speaker 1: these and use symmetries to like break down the problem
44:54
Speaker 1: into smaller pieces, to organize this complexity, and that helped
44:58
Speaker 1: to make sort of like approximate statements about which kinds
45:01
Speaker 1: of spin glass final states were more likely than others,
45:04
Speaker 1: like if you started here, you're likely to get to
45:07
Speaker 1: neighboring final states where you weren't going to make a
45:10
Speaker 1: big jump to something all the way on the other
45:12
Speaker 1: side of the sort of symmetry organized set of states.
45:16
Speaker 1: And you're talking about math that sort of analyzes one
45:19
Speaker 1: of these grids right like you're looking at a grid
45:21
Speaker 1: of these atoms, these frustrated atoms, together, and you're trying
45:24
Speaker 1: to figure out, like, you know, are they all gonna
45:27
Speaker 1: go up or down, or is they are they going
45:28
Speaker 1: to alternate or are they gonna you know, how often
45:31
Speaker 1: are you going to run into an up spin atom?
45:34
Speaker 1: And you're wondering, if I poke this thing, how likely
45:37
Speaker 1: is it to change to another configuration, or how likely
45:40
Speaker 1: is it, after I've poked it, to come back to
45:42
Speaker 1: this configuration? or how many spins are going to be
45:45
Speaker 1: flipped after I poke it? Is it going to be
45:47
Speaker 1: every single thing is flipped, or just a fraction of
45:49
Speaker 1: you or flipped. So those the kind of questions people
45:52
Speaker 1: are interested in, just like what are the behaviors of
45:54
Speaker 1: these things? So press math gave us sort of like
45:57
Speaker 1: a map for all those different configurations. He said like okay,
46:00
Speaker 1: this configuration of the spin glass, you can put it
46:03
Speaker 1: here on the map, and he was able to sort
46:04
Speaker 1: of organize and create this idea of a distance between
46:08
Speaker 1: one spin configuration and another. This distance is sort of
46:11
Speaker 1: a mathematical way to calculate like how many spins are
46:14
Speaker 1: similar or not, and he was able to organize it
46:17
Speaker 1: in such a way that he showed that if you
46:18
Speaker 1: poke this thing was more likely to end up in
46:21
Speaker 1: a nearby configuration than a distant one, where the distance
46:25
Speaker 1: here is something that he defined his strategy for organizing
46:29
Speaker 1: these different configurations. So there is a pretty interesting kind
46:32
Speaker 1: of material. I guess kind of to go back a
46:34
Speaker 1: little bit to my earlier question is, you know, like
46:37
Speaker 1: let's say I make a piece of quantum glass and
46:39
Speaker 1: it has these interesting mathematical properties. What could I do
46:42
Speaker 1: with it? Can I like make actual glasses out of
46:45
Speaker 1: this glass? What would happen if I see through it?
46:48
Speaker 1: Only if you can see through solid gold or silver
46:50
Speaker 1: or copper. You know, there's not anything that I'm aware
46:53
Speaker 1: that you can like do with it in your life
46:55
Speaker 1: other than impress your physicist friends, which you know, has
46:59
Speaker 1: its own inherent value. I mean it is sort of
47:01
Speaker 1: a quantum object, isn't it? At the end of the day,
47:03
Speaker 1: this glass is a quantum object. Could you do quantum
47:06
Speaker 1: things with it? Or computation for a bit? Possibly? I'm
47:09
Speaker 1: not aware of any applications for quantum computing. But I
47:12
Speaker 1: think with the most interesting thing is just the math
47:14
Speaker 1: that it makes us think about. It made these guys
47:16
Speaker 1: think about symmetries and patterns in new ways and come
47:20
Speaker 1: up with new mathematical tools. And whenever we develop new
47:23
Speaker 1: mathematical tools we always find out that they're useful in
47:26
Speaker 1: other places. So people have been thinking about these kinds
47:29
Speaker 1: of symmetries and crystals for decades and decades in the
47:32
Speaker 1: field we called condensed matter, the study of, you know,
47:36
Speaker 1: dense objects like crystals, and because of that Mathematical Foundation
47:39
Speaker 1: laying in condensed matter there's a lot of work on symmetries,
47:43
Speaker 1: a lot of which informed Peter Higgs when he was
47:46
Speaker 1: thinking about why particles get mass. He came up with
47:48
Speaker 1: this idea of another field in the universe that imparts
47:51
Speaker 1: the mass. But this field has to be really weird
47:54
Speaker 1: and different from any other field he had seen before.
47:57
Speaker 1: It would have to settle and relax into an on
48:00
Speaker 1: minimum energy state. As we've talked about in the program
48:03
Speaker 1: a lot of times. The Higgs field has some weird
48:05
Speaker 1: energy bound into it. It can't relax to its lowest
48:08
Speaker 1: energy state. It relaxed to this weird intermediate state, and
48:12
Speaker 1: so thinking about the symmetry of that problem helped him
48:15
Speaker 1: think about the symmetries and the broken symmetries of the
48:17
Speaker 1: Higgs field and really inspired that Whole Direction of mathematics
48:21
Speaker 1: and particle physics. And that kind of worked out right
48:25
Speaker 1: for Peter Higgs and the press of humanity. But Peter
48:29
Speaker 1: Higgs didn't know about these quantum glass is right. You're
48:33
Speaker 1: just saying that they sort of use the same kind
48:35
Speaker 1: of math and that's why it could be important. That's right.
48:37
Speaker 1: Quantum glasses weren't well understood when he was talking about
48:41
Speaker 1: this kind of stuff and he was thinking about it.
48:42
Speaker 1: But the mathematics that underlie condensed matter and understanding these
48:47
Speaker 1: symmetries led to both a deeper understanding of quantum glasses
48:51
Speaker 1: and of symmetry breaking and the Higgs field. Well, it's
48:54
Speaker 1: interesting that there is a connection, right. I mean there's
48:56
Speaker 1: a connection between the such a fundamental particle in the
48:59
Speaker 1: universe and maybe all particles and what happens at these
49:02
Speaker 1: kind of microscopic levels. Right, maybe the idea that the
49:06
Speaker 1: universe is there's a lot about symmetry in the universe.
49:08
Speaker 1: There is a lot about symmetry in the universe and
49:10
Speaker 1: also about these emergent phenomena. We've talked several times in
49:13
Speaker 1: the podcast about things we call quasi particles. These are
49:17
Speaker 1: weird materials that have states in them that looks sort
49:20
Speaker 1: of like particles that act sort of like particles, you know,
49:23
Speaker 1: like phonons, are waves that pass through a lattice in
49:27
Speaker 1: the crystal and they're sort of similar to photons, but
49:30
Speaker 1: instead of moving through the fundamental electromagnetic field of the universe,
49:34
Speaker 1: they're moving through a crystal lattice. So we see these
49:37
Speaker 1: same kind of properties emerging in condensed matter that we
49:40
Speaker 1: often see also in the quantum fields of the universe,
49:44
Speaker 1: and so there's a lot of connections between the mathematics
49:47
Speaker 1: of solid objects and the mathematics of Space Time itself.
49:51
Speaker 1: Does that inspire you to make your office more symmetric,
49:55
Speaker 1: or do work in at causant state of frustration as well? No,
49:57
Speaker 1: I'm always asking my department here. I'm like, can I
49:59
Speaker 1: get a bunch of gold bricks? I'd like to build
50:01
Speaker 1: a really strict, nice lattice to study their symmetry, but
50:04
Speaker 1: so far having gotten a single delivery of a single
50:07
Speaker 1: gold brick. And you just need to let him your
50:09
Speaker 1: quantum glasses so he can see the future as well.
50:12
Speaker 1: Or maybe he's just gonna Send Me Microscopic Quantum gold bricks,
50:15
Speaker 1: whether either here nor there. Here's one atom of gold.
50:19
Speaker 1: Good luck in this economy. I'd be very happy for
50:21
Speaker 1: even one atom. All right, well, this is an interesting
50:25
Speaker 1: new kind of material and with interesting properties that we're
50:29
Speaker 1: learning more about, and it sounds like it's just another
50:31
Speaker 1: example of the weird things we can find and in
50:33
Speaker 1: this messy universe. You know, like maybe thirty years ago
50:37
Speaker 1: we would never have imagined that we can make a
50:39
Speaker 1: material that is magnetically frustrated. Yeah, and despite all the
50:42
Speaker 1: mess that we find around us, we can still seek
50:45
Speaker 1: order and find patterns and mathematical tricks to analyze it,
50:49
Speaker 1: which turned out to not just help us understand the
50:52
Speaker 1: stuff around us, but also reveal the mathematical patterns that
50:55
Speaker 1: seem to be inherent in the universe itself. Well, we
50:59
Speaker 1: hope you aoid dad. Thanks for joining us. Go have
51:02
Speaker 1: a shot of some quantum drink. have an electron on me.
51:06
Speaker 1: See you next time. Thanks for listening, and remember that
51:16
Speaker 1: Daniel and Jorge explain the universe is a production of
51:19
Speaker 1: I heart radio. For more podcast from my heart radio,
51:23
Speaker 1: visit the I heart radio APP, apple podcasts or wherever
51:27
Speaker 1: you listen to your favorite shows. Yeah,