Latest / Daniel and Kelly’s Extraordinary Universe / Is it possible to have a two-dimensional object?

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Is it possible to have a two-dimensional object? · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: Hey, Daniel, you used to live in Chicago, right, Yeah,
0:11
Speaker 1: I did when I was working at the accelerator at Fermulab.
0:14
Speaker 1: Does that mean you're like Chicago style pizza? Oh my god,
0:17
Speaker 1: that is not pizza. That's like a castle roll, that's
0:20
Speaker 1: like a mara neara swimming pool. I mean it's delicious,
0:23
Speaker 1: of course, but it's not actually pizza is our tough
0:26
Speaker 1: words for a Chicago style pizza. Does that mean you
0:29
Speaker 1: prefer it in pizza like New York style pizza? Oh? Yeah, absolutely,
0:32
Speaker 1: like the thinner the better, really like health it. I
0:36
Speaker 1: don't know if it was possible. I guess I need
0:38
Speaker 1: a two dimensional slice of pizza. Well that's convenient. Then
0:41
Speaker 1: you can eat all the pizza you like and in
0:43
Speaker 1: the end you have eaten nothing. What about the toppings?
0:46
Speaker 1: Do you like to the toppings too? Maybe that's why
0:49
Speaker 1: people in New York or so thin. They have no death,
0:54
Speaker 1: they're so shallow. Hi am or handmade cartoonist and the
1:12
Speaker 1: creator of PhD comics. Hi. I'm Daniel. I'm a particle physicist,
1:16
Speaker 1: and I really do have strong opinions about pizza. Really yes,
1:19
Speaker 1: strong penis about particles, about physics and about pizza and
1:23
Speaker 1: dessert and big goods. You have a lot of strong opinions, Daniel,
1:26
Speaker 1: I am particular about pizza, and yes, big goods the
1:29
Speaker 1: things I enjoy. I know what I like, and I
1:31
Speaker 1: do love thin New York or Italian style pizza, but
1:35
Speaker 1: also a nice big slab of Chicago style whatever you
1:38
Speaker 1: call it is also delicious whatever. And you don't even
1:42
Speaker 1: want to call it a pizza. I don't know. It's
1:44
Speaker 1: just a totally different kind of food. I mean, the
1:46
Speaker 1: only thing they have in common are carbs, cheese, and
1:48
Speaker 1: tomato sauce. Yeah, that's a pizza. Does that mean that
1:51
Speaker 1: you know? Pasta with tomato sauce and parmesan on top
1:54
Speaker 1: is also a pizza and a calzone is just a
1:57
Speaker 1: close pizza. That's a pizza taca. But welcome to our podcast.
2:02
Speaker 1: Daniel and Joorhead apparently talk about pizza and explain the
2:05
Speaker 1: universe in production of I Heart Radio, a podcast which
2:08
Speaker 1: we record just before lunch if you can't tell, and
2:11
Speaker 1: we usually talk about all the crazy things out there
2:14
Speaker 1: in the universe, the amazing ways that matter conform, the
2:17
Speaker 1: weird things that they can do, from really really big
2:21
Speaker 1: stuff like entire galaxies and clusters of galaxies down to
2:24
Speaker 1: really strange little objects, what those tiny little dancing particles
2:28
Speaker 1: can make when they set their minds to it. That's right, because,
2:31
Speaker 1: let's face it, we're all hungry, hungry for knowledge in
2:34
Speaker 1: this world. You all want to know what everything is
2:37
Speaker 1: made out of, how it all works, and how it's
2:39
Speaker 1: all put together, and how it all makes sense if
2:41
Speaker 1: it does. That's right. I would like to order two
2:43
Speaker 1: slices of truth for lunch. Please you have a Nobel
2:46
Speaker 1: price there on top. Please just shaved Nobel prize on top.
2:50
Speaker 1: That sounds pretty good. Yeah, you know, like gold shavings,
2:52
Speaker 1: something that's edible. Right, you can also do that with
2:55
Speaker 1: a Nobel price. You know, just adds a little bit
2:57
Speaker 1: of intellectual richness to the smartest pizza ever. Yeah. We
3:02
Speaker 1: like to talk about all the amazing things in the universe,
3:04
Speaker 1: all of the crazy stars and galaxies and black holes
3:07
Speaker 1: and neutron stars out there, and also all of the
3:10
Speaker 1: little tiny parkles that make us up who we are
3:13
Speaker 1: and that pizza that you had for lunch. And we
3:16
Speaker 1: also like to think about the way the world is
3:18
Speaker 1: and why isn't it another way? Something I like to
3:22
Speaker 1: think about a lot when I was younger, and even
3:24
Speaker 1: still today. Are the number of dimensions of space, you know,
3:28
Speaker 1: the way that we can move three D? And what
3:30
Speaker 1: it would be like to be a four dimensional being
3:32
Speaker 1: or to be a two dimensional being in a three
3:35
Speaker 1: dimensional world. These kind of mental exercises were fun for
3:38
Speaker 1: me and made me wonder like, why do we live
3:39
Speaker 1: in a three dimensional world? What would it be like
3:42
Speaker 1: to live in a universe with a different number of dimensions? Wow,
3:45
Speaker 1: that's what you wondered about as a kid. I was
3:47
Speaker 1: wondering like how does Superman fly? And how strong is
3:51
Speaker 1: Spider Man's web? You know, you're wondering about the dimensions
3:54
Speaker 1: of the universe. I was. I mean that this is
3:56
Speaker 1: not six year old Daniel, this is probably fourteen year
3:58
Speaker 1: old Daniel, But yeah, I was thinking about that stuff.
4:01
Speaker 1: What if Superman was two dimensions? How many dimensions are
4:04
Speaker 1: there too Spider Man's web? After all? So yeah, I
4:06
Speaker 1: think these questions are super fun and they go to
4:08
Speaker 1: the heart of a really basic question, which is why
4:11
Speaker 1: is our universe the way that it is? So that's
4:14
Speaker 1: why it's fun to explore these different kinds of objects
4:17
Speaker 1: and different kinds of geometries. And I remember thinking, what
4:20
Speaker 1: if there are other parts of the universe in which
4:22
Speaker 1: there are four or five dimensions of space? What if
4:25
Speaker 1: we are like trapped in a three dimensional subset of
4:27
Speaker 1: the universe. Yeah, oh, man, I think fourteen year old
4:30
Speaker 1: Jorge was definitely not wondering about physics. He's probably wondering
4:34
Speaker 1: about things we can't mention in this podcast. But yeah,
4:37
Speaker 1: this idea of dimensions is pretty mind blowing. I mean,
4:39
Speaker 1: it's not something we think about every day, right. We're
4:42
Speaker 1: also used to living in this world with three dimensions,
4:45
Speaker 1: you know, up, down, left, right, front and back, and
4:48
Speaker 1: it's kind of hard to wrap your head around or
4:50
Speaker 1: even imagine more dimensions or even less dimensions. Yeah, it
4:55
Speaker 1: really is hard to because we are so used to this.
4:58
Speaker 1: But this is something we're doing in physics all the time,
5:00
Speaker 1: is wondering if the way we think about the world
5:03
Speaker 1: is just based in our experience and maybe therefore not universal,
5:07
Speaker 1: not representative. Right. We don't want to imagine the whole
5:10
Speaker 1: universe is just the way that we have experienced it.
5:12
Speaker 1: We want to break out of those intellectual chains. We
5:15
Speaker 1: want to be surprised, We want to discover that the
5:17
Speaker 1: universe is totally different. And that's why science is such
5:20
Speaker 1: an amazing tool, because it lets us put aside our
5:23
Speaker 1: biases and chip away at the truth. Yeah, we want
5:26
Speaker 1: to free our minds. That we do. We want to
5:29
Speaker 1: blow all of our minds. Yeah. Is it kind of
5:31
Speaker 1: like fish? You know, they live in the water their
5:33
Speaker 1: whole lives. They probably think the whole universe is made
5:35
Speaker 1: out of water, and you know there's nothing but water. Yeah, precisely,
5:39
Speaker 1: because they've never experienced anything else, and so how could
5:42
Speaker 1: they possibly extrapolate? And it's only when they see weird
5:45
Speaker 1: things like the water seems to have an edge, I
5:48
Speaker 1: wonder what's beyond it? When they start asking those questions
5:51
Speaker 1: about other parts of the universe, do they expand their
5:53
Speaker 1: minds and understand like the true nature of the universe.
5:57
Speaker 1: And we've done this lots of times as humans, discovering
5:59
Speaker 1: the univers pretty different from the one that our ancestors
6:02
Speaker 1: thought it was, which means there are probably crazy discoveries
6:06
Speaker 1: ahead where in two hundred years people will look back
6:08
Speaker 1: and think, I can't believe they used to think X,
6:11
Speaker 1: Y Z, whatever it is we're thinking now. Yeah, I
6:13
Speaker 1: wonder if fish go fishing for ideas Also, I wonder
6:16
Speaker 1: if they play Go Fish or if they have another
6:18
Speaker 1: game called Go Human or something. And when are the
6:20
Speaker 1: New York style pizza. Now that's a mind blowing multidimensional
6:24
Speaker 1: question right there. Well, you can't eat Chicago pizza without
6:27
Speaker 1: a knife and fork, and they don't have hands, So
6:29
Speaker 1: I think that's answered. You can put on shovies, and
6:31
Speaker 1: then that brings it all around to the fish idea.
6:34
Speaker 1: But getting back to our dimensional question, it is weird
6:37
Speaker 1: to think about the world universe having more than three dimensions,
6:41
Speaker 1: and so this is something that physicists actually consider, and
6:44
Speaker 1: some of them even think there are not just four
6:47
Speaker 1: or five dimensions. There's a whole bunch of dimensions out there.
6:49
Speaker 1: That's right. Even physicists that don't like anchovies think about
6:52
Speaker 1: the world is having eleven or twenties six dimensions. Some
6:57
Speaker 1: of these theories that unify gravity and wanted mechanics, things
7:01
Speaker 1: like string theory, which might be candidate for a theory
7:04
Speaker 1: of everything. These work best if there are more dimensions
7:08
Speaker 1: of space and time for the forces and these strings
7:11
Speaker 1: to sort of wiggle in. The mathematics prefers eleven or
7:14
Speaker 1: twenty six dimensions, which is pretty hard to get your
7:17
Speaker 1: mind around, like where are those dimensions? How do you
7:20
Speaker 1: move in those dimensions? Why do we only experience three
7:22
Speaker 1: if there are eleven or twenty six? Yeah, and equally
7:26
Speaker 1: as mind blowing is to think it's sort of in
7:28
Speaker 1: the other direction, right to think about what if the
7:30
Speaker 1: world had less dimensions in three or what if there
7:33
Speaker 1: are things out there that are a less than three
7:36
Speaker 1: dimensionals in their being. That's a super fun idea. And
7:39
Speaker 1: there's this whole class of theories that suggests that maybe
7:42
Speaker 1: the entire three D universe is actually just a hologram
7:46
Speaker 1: of a two dimensional universe, meaning that we are actually
7:49
Speaker 1: two dimensional beings. We're gonna do a whole podcast episode
7:52
Speaker 1: about the holographic universe later on. But that's a really
7:54
Speaker 1: powerful idea actually in string theory, that lets people do
7:57
Speaker 1: calculations that otherwise would be impossible. I feel like this
8:00
Speaker 1: podcast is kind of two dimensional, Daniel, because you know,
8:03
Speaker 1: we don't go very deep here, No, we have to
8:05
Speaker 1: pick one topic to go deep on, but we're always
8:08
Speaker 1: touching on other things, and I'm always like, oh, remember
8:10
Speaker 1: that time we talked about this, Or that's an idea
8:12
Speaker 1: for another episode, or this is fascinating but the digression
8:15
Speaker 1: would take another forty five minutes, so let's save it
8:17
Speaker 1: for a whole other episode. I see what you're saying.
8:19
Speaker 1: Every other podcast is one dimensional. We are two dimensional.
8:22
Speaker 1: We're like the world's first two D podcast. I don't know,
8:25
Speaker 1: maybe we're zero dimensional. I can't even tell. What does
8:28
Speaker 1: it mean to have a dimensionality and audio? I guess
8:31
Speaker 1: we're in stereos that's two D maybe. But anyway, so
8:33
Speaker 1: today we're gonna explore this question. On the other side
8:37
Speaker 1: is wondering what could there be and are there things
8:40
Speaker 1: that are less than three dimensions? Yeah, because it's fun
8:42
Speaker 1: to think about what it would be like to be
8:44
Speaker 1: in a four dimensional world. If you were a three
8:47
Speaker 1: D person in a four dimensional world, we talked about
8:49
Speaker 1: that on a podcast recently, you could disappear from inside
8:53
Speaker 1: of prison and appear on the outside of it by
8:55
Speaker 1: moving in the direction of that fourth dimension. So it's
8:58
Speaker 1: also fun to think about, like, well, do we have
9:00
Speaker 1: objects in our world which are two dimensional which don't
9:03
Speaker 1: see this third dimension where we could do these crazy
9:05
Speaker 1: tricks on them. Yeah, So today on the podcast, we'll
9:08
Speaker 1: be asking the question can an object be two dimensional? Now, Daniel,
9:18
Speaker 1: is that too like the number two, or like, are
9:21
Speaker 1: you asking if something can have too many dimensions? Yeah?
9:24
Speaker 1: My wife says that to me all the time. Man,
9:26
Speaker 1: you are too dimensional. Stop being so dimensional. Yeah. I
9:30
Speaker 1: think he's starting to tell you you need to go
9:31
Speaker 1: in a diet. Maybe she's like, you have too many dimensions.
9:35
Speaker 1: You need to stop eating so much at New York
9:37
Speaker 1: style pizza. Yeah, I suppose. I suppose I need you
9:39
Speaker 1: to have some fractional dimensions. So this is a kind
9:42
Speaker 1: of a crazy question. Question is can an object the
9:44
Speaker 1: two dimensional, like the object itself only exists in two dimensions,
9:49
Speaker 1: or you know, maybe it exists in a subset of
9:52
Speaker 1: our dimensions, or does it mean that it's just like
9:56
Speaker 1: super thin. Yeah, I think the answer is yes to
9:58
Speaker 1: all of those. We exist in three dimensions, and so
10:01
Speaker 1: every object you look at exists in three dimensions. Every
10:04
Speaker 1: piece of food you've eaten, everything you've tripped over, everything
10:07
Speaker 1: you've looked at exists in three dimensions because it's in
10:10
Speaker 1: this three D space. And it's hard to imagine an
10:13
Speaker 1: object having four dimensions in our three D space. But
10:16
Speaker 1: why can't it? Objects have two dimensions be essentially only
10:20
Speaker 1: X and y and have no height right to be
10:22
Speaker 1: a super thin slice. Is that possible to have a
10:26
Speaker 1: lower dimensional object in our universe? Yeah, so this is
10:30
Speaker 1: a kind of a mind blowing question. And so as
10:33
Speaker 1: usual we were wondering how many people out there had
10:35
Speaker 1: thought about this question and whether or not they have
10:37
Speaker 1: an answer to this strange and um multidimensional or a
10:42
Speaker 1: dual dimensional quarry. So, as usual Daniel went out there
10:44
Speaker 1: into the wilds of the internet to ask people can
10:47
Speaker 1: an object be two dimensional? Thanks again to our willing volunteers.
10:51
Speaker 1: And if you would like to answer some questions about
10:54
Speaker 1: tricky topics and here your speculation on the podcast, please
10:57
Speaker 1: write to me two questions at Daniel and Jorge dot com.
11:01
Speaker 1: It's what people had to say. I don't really think
11:03
Speaker 1: that an object can be two dimensionals in a three
11:05
Speaker 1: dimensional space that we live in. But if I think
11:08
Speaker 1: about it, what is a volume of an object? It
11:11
Speaker 1: is the space between the particles and not the particles themselves.
11:15
Speaker 1: So if the particles somehow could form a perfectly flat
11:19
Speaker 1: sheet so that they only extent in the extent y
11:23
Speaker 1: axis but they don't go into the Z direction, that
11:26
Speaker 1: theoretically maybe we could call an object like this to
11:29
Speaker 1: be a two dimensional object. I suppose an object technically
11:33
Speaker 1: can't be two dimensional because as songs have volume and
11:37
Speaker 1: or there for three dimensional. But I think there are
11:41
Speaker 1: um situations where, for instance, if you have one layer
11:45
Speaker 1: of graphine it is so thin that it is treated
11:48
Speaker 1: as if it's two dimensional. Then I am not sure
11:52
Speaker 1: about this, but I think um with the modesty in
11:57
Speaker 1: a conjecture, because with the conform of fuel theory, you
12:02
Speaker 1: treat a three dimensional object, for instance a black hole
12:06
Speaker 1: by looking only at its UM like surface or surface
12:12
Speaker 1: area UM by translating it from the strength theories of
12:17
Speaker 1: the cf G, you almost treated as if it's two dimensional.
12:21
Speaker 1: I think, um, that might be an example. Alright, some
12:26
Speaker 1: skepticism here, and none of these two said, yes, something
12:29
Speaker 1: can be too D. We got rejected exactly, and you
12:32
Speaker 1: had a third answer also, but no one didn't make
12:35
Speaker 1: the cut. Is that a two D three D joke
12:39
Speaker 1: joke out of this flat topic that I'm impressed by
12:42
Speaker 1: the depth of your sense of humor? All right, So
12:44
Speaker 1: none of the answers seem to think you can have
12:46
Speaker 1: it to the object. One of them said that because
12:48
Speaker 1: adams have volume, and the other one said because we
12:51
Speaker 1: live in a three D space. So let's get into
12:54
Speaker 1: these strange conundrums. So Daniel, first of all, what would
12:57
Speaker 1: you say, is it to D object? How would you define?
13:00
Speaker 1: As usual? The definition is going to be critical is
13:03
Speaker 1: to exactly what we mean by two D object. But
13:06
Speaker 1: let's start like, really theoretically, in an idealized sense, I
13:10
Speaker 1: think the world is having three dimensions, in the sense
13:13
Speaker 1: that there's three extensions, right, three coordinates. You need to
13:16
Speaker 1: define your location in space, and so you can think
13:20
Speaker 1: of an object having like one dimension is aligned two dimensions,
13:24
Speaker 1: would be a square and any height on that square
13:26
Speaker 1: would make it a cube. I would make it three dimensions.
13:29
Speaker 1: So a two D object would be something that had
13:33
Speaker 1: no measurement in the third dimension, that it's location in
13:36
Speaker 1: the third dimension had only one edge, not two edges,
13:40
Speaker 1: doesn't have like a start and an end. It's start
13:42
Speaker 1: and end are exactly the same location. So it's you know,
13:46
Speaker 1: it would be essentially infinitely flat sheet of paper for example.
13:50
Speaker 1: You see, So it's an object, it has to be
13:52
Speaker 1: like a physical thing in our world that really only exists,
13:56
Speaker 1: like it only takes up space in one direction. Like
14:00
Speaker 1: you said, it's invisible if you look at it kind
14:02
Speaker 1: of on the side. Yeah, because it can't exist in
14:05
Speaker 1: the third dimension. That means that if you measured its height,
14:08
Speaker 1: the top of it and the bottom of it would
14:10
Speaker 1: be exactly the same number. Right, there's no height to
14:14
Speaker 1: it at all, because anything more than zero would mean
14:17
Speaker 1: there's an extent in that third dimension, and then it's
14:19
Speaker 1: just pretty thin, not exactly fin that. We're looking for
14:22
Speaker 1: something which really has zero height in that third dimension,
14:25
Speaker 1: but it needs to exist in our space so we
14:27
Speaker 1: can interact with it. You can see it from the side,
14:30
Speaker 1: for example. That's the question, can an object like that exist?
14:33
Speaker 1: An object on which you were a person and you
14:36
Speaker 1: were walking around, you wouldn't even notice that there was
14:38
Speaker 1: a third dimension because you would only exist on that
14:41
Speaker 1: too D space, you know, basically flat land. Yeah, and
14:43
Speaker 1: my cartoonists and so, you know, making things two days.
14:47
Speaker 1: It's kind of my jam. But I think it's also
14:50
Speaker 1: pretty cool to think about, like what happens if you
14:52
Speaker 1: have multiple of these infinitely flat objects, Like if you
14:55
Speaker 1: stuck in a whole bunch of them together, they would
14:58
Speaker 1: still be flat, they would still have zero height. Yeah,
15:01
Speaker 1: because any number of times zero is zero. So you
15:05
Speaker 1: can eat an infinite number of slices of two D
15:08
Speaker 1: pizza and you've eaten zero volume of pizza. You won't
15:11
Speaker 1: even grow in one dimension like your belt size dimension
15:15
Speaker 1: no is zero volume right, So that means essentially you
15:18
Speaker 1: can't have a two D slice of pizza. Can you
15:20
Speaker 1: taste it? Though? Maybe you can taste it like if
15:22
Speaker 1: it hits your tongue? You know, is that possible? Thin?
15:25
Speaker 1: Have we invented the perfect two D diet? Two D
15:28
Speaker 1: Quantum Diet by Daniel? Download the app mat we will
15:32
Speaker 1: sputter a layer of pizza two D pizza onto your tongue. Yeah,
15:36
Speaker 1: because you can't pick it up right? Well, I guess
15:38
Speaker 1: the question is is it possible at all to have
15:40
Speaker 1: an object that is like that, that is infinitely thin?
15:43
Speaker 1: Are there loss of physics that would prevent it? Or
15:46
Speaker 1: is it theoretically possible? So I still have three answers
15:49
Speaker 1: to that, you know, yes, a no, and then maybe
15:51
Speaker 1: so starting with a yes. You know that everything in
15:54
Speaker 1: our world is built out of particles and particles in
15:58
Speaker 1: our model, how many dimensions do they have? Well, we
16:02
Speaker 1: think of them as points. There are point particles. We
16:05
Speaker 1: don't know if the electron has any substructure in it,
16:08
Speaker 1: so we treat it as if it doesn't. We consider
16:11
Speaker 1: it to be a dot, essentially an infinitely small dot.
16:14
Speaker 1: That means it's zero dimensional so in our theory, and
16:18
Speaker 1: electron takes up no volume. So if you can have
16:21
Speaker 1: a zero D particle, you can make a one D
16:23
Speaker 1: object by having two of them, and then the line
16:26
Speaker 1: between them is a one D object, and four of
16:28
Speaker 1: them are actually just three of them make a plane
16:31
Speaker 1: that in principle is a two dimensional object. So that's
16:35
Speaker 1: sort of the yes answer on the theoretical idea. Like
16:38
Speaker 1: if I took one atom or like one quirk right,
16:42
Speaker 1: and I lined it up with like a hundred other
16:44
Speaker 1: quarts in the same line, that would technically be an
16:48
Speaker 1: object by our regular definition, but it would have only
16:51
Speaker 1: one dimension technically exactly if you believe that particles are
16:55
Speaker 1: zero dimensional, and you know, I don't really know if
16:57
Speaker 1: that really flies, because particles are an excitation in a
17:01
Speaker 1: quantum field and they're localized, so probably not exactly zero dimensional.
17:06
Speaker 1: But if you start from a zero dimensional particle, then yes,
17:09
Speaker 1: a line of them is a one dimensional object. I
17:11
Speaker 1: guess the problem is that you know particles are point objects,
17:15
Speaker 1: but they have kind of a three D presence. Yes,
17:18
Speaker 1: they do have a three D presence, because how would
17:20
Speaker 1: you build that one D line of quarks. The way
17:24
Speaker 1: that you connect things is through their forces, right. The
17:27
Speaker 1: reason that an atom is an atom is because of
17:29
Speaker 1: the forces that bind the electron to the proton, and
17:33
Speaker 1: those forces, as you say, have a three D presence.
17:36
Speaker 1: And if you have a pile of hydrogen, for example,
17:38
Speaker 1: the reason it's not just all in one spot is
17:40
Speaker 1: that those atoms repel each other, and so there are
17:43
Speaker 1: forces between them that give an object volume, and that
17:47
Speaker 1: volume is then three dimensional because the forces are three dimensional, right,
17:51
Speaker 1: But I guess even those forces could fall on that line.
17:53
Speaker 1: Like let's say you empty out the universe. The universe
17:56
Speaker 1: is empty and you only have two quarks. That's technically
17:59
Speaker 1: to the object, that's a two D object, But it
18:01
Speaker 1: fails the other test, like could you stack another one
18:03
Speaker 1: on top of it exactly and get zero height? If
18:06
Speaker 1: you bring another one next to it, it would not
18:08
Speaker 1: want to be exactly on top of it, And so
18:11
Speaker 1: really it's a three D object. It's just sort of
18:13
Speaker 1: like a very thin tube. All right, That was your
18:16
Speaker 1: yes answer? What's your maybe answer? So The yes answer
18:19
Speaker 1: was start from zer D particles, you can The no
18:21
Speaker 1: answer was zer y particles really have three D forces,
18:24
Speaker 1: So no, The maybe answer is remember that our world
18:28
Speaker 1: is quantum mechanical, and so in some sense you don't
18:32
Speaker 1: have to have infinite thinness to be minimal thinness. Right,
18:37
Speaker 1: our universe has a minimal length. So now imagine an
18:41
Speaker 1: object which is normal in one dimension and in the
18:44
Speaker 1: second dimension, but in the third dimension it has the
18:47
Speaker 1: minimal length like the just one space pixel essentially wide,
18:51
Speaker 1: that you might consider to be a two dimensional object. Oh,
18:55
Speaker 1: I see, by like the definition of space in the universe,
18:58
Speaker 1: if something is thinner than the quantum minimum distance, then
19:03
Speaker 1: you you kind of have to say it's flat, perfectly flat, right,
19:07
Speaker 1: because you can't resolve that it's any thinner. You couldn't
19:11
Speaker 1: have a thinner object except for in your mind as
19:13
Speaker 1: a geometer imagining perfect to D objects. But in our
19:17
Speaker 1: universe things you could build, you couldn't have a thinner object.
19:20
Speaker 1: So you should crown that to be either the thinnest
19:23
Speaker 1: three dimensional object possible or a two D object. And
19:27
Speaker 1: we'll talk about it a little bit later, but there
19:29
Speaker 1: are some objects like that in our universe that follow
19:32
Speaker 1: the math for two D objects. Interesting, it gets complicated.
19:36
Speaker 1: We'll have to go deep. We'll have to have tried
19:40
Speaker 1: to avoid being shallow. All right, well, let's get it
19:42
Speaker 1: into whether or not there are theoretically to the objects
19:46
Speaker 1: out there and whether or not they exist in the
19:48
Speaker 1: real world. At first, let's take a quick break. Alright,
20:04
Speaker 1: we're talking about to the objects, Daniel, And now this
20:06
Speaker 1: is a podcast. Does that mean that listeners have to
20:08
Speaker 1: put on like two d your phone, like a red
20:12
Speaker 1: and a blue one. Would that help? Well, they're hearing
20:14
Speaker 1: the answers in two d right, one from me and
20:15
Speaker 1: one from you. I guess, yeah, dude, two dudes, just
20:19
Speaker 1: two dads or dudes. So technically it is a to
20:23
Speaker 1: D podcast, that's right. And sometimes we agree with each
20:25
Speaker 1: other and sometimes we don't. Sometimes I'm negative, sometimes we
20:29
Speaker 1: cancel out. It's all a math problem. Hopefully there's constructive
20:33
Speaker 1: interference in the explanation to mention. All right, you just
20:35
Speaker 1: went too deep there. I guess one question you can
20:38
Speaker 1: ask is whether or not you can theoretically have to
20:41
Speaker 1: the objects. And as I understand that the physics does
20:44
Speaker 1: allow for theoretical to the objects, yea theoretical to D
20:47
Speaker 1: objects are not a problem. But we talked before about
20:50
Speaker 1: this idea of the universe as a hologram. Is there
20:53
Speaker 1: a really powerful idea, and it shows that all the
20:57
Speaker 1: information in a three dimensional space can actually be encoded
21:01
Speaker 1: on the surface of that space. You know, take like
21:05
Speaker 1: a sphere and imagine all the stuff inside of it,
21:08
Speaker 1: all the physics that's going on inside that sphere might
21:11
Speaker 1: actually just be encoded on the surface of that sphere.
21:15
Speaker 1: And that's a really powerful idea because it helps people
21:17
Speaker 1: do some calculations, like there's two totally different kinds of
21:21
Speaker 1: theories that have different dimensions, and this links them together.
21:24
Speaker 1: It's really important results for string theory. But also it's
21:27
Speaker 1: really cool for thinking about black holes, like what's inside
21:30
Speaker 1: a black hole? And is it possible that all the
21:33
Speaker 1: information inside a black hole is actually just embedded on
21:36
Speaker 1: the surface of the event horizon. Yeah, we had a
21:39
Speaker 1: whole podcast about whether or not the universe is a
21:41
Speaker 1: hologram imprinted on the surface of a black hole. And
21:45
Speaker 1: you know, as a cartoonist, I'm a big believer in
21:47
Speaker 1: that you can capture whole worlds in a sheet of paper.
21:50
Speaker 1: You know, it's my whole philosophy of life. But I
21:54
Speaker 1: guess the question is, you know, it's cool that you
21:56
Speaker 1: can maybe project the whole three D world into a
21:58
Speaker 1: two D surface, like for example of a black hole,
22:01
Speaker 1: But don't you lose information like in a cartoon, I
22:03
Speaker 1: don't know what's standing behind my cartoon characters, Like, wouldn't
22:08
Speaker 1: that information get lost? Yeah? So there's three spatial dimensions
22:11
Speaker 1: in the universe and then two spatial dimensions on the surface,
22:14
Speaker 1: But there are quantum fields on that two dimensional surface,
22:17
Speaker 1: and those fields can encode all sorts of information. Like
22:20
Speaker 1: a field can have multiple dimensions. It can be a
22:23
Speaker 1: vector field. For example, at every point in space, a
22:27
Speaker 1: field can have more than one number. You can have
22:29
Speaker 1: an entire vector, which is three numbers, or five numbers
22:32
Speaker 1: or ten numbers. So you could have lots of information
22:34
Speaker 1: sort of packed into every unit of space. So even
22:37
Speaker 1: though the space has fewer dimensions, the fields in that
22:41
Speaker 1: space could have more information sort of per unit of space,
22:44
Speaker 1: so you end up with the same amount of information.
22:47
Speaker 1: You mean, you're cheat. It comes down to the definitions.
22:53
Speaker 1: I mean, it's it's kind of like you just stacking
22:54
Speaker 1: pixels on top of each other, kind of right. It's
22:57
Speaker 1: kind of like in a three D movie that you
22:59
Speaker 1: when you go to the theater, it's like it's the
23:01
Speaker 1: same screen, but it's giving you twice the amount of
23:03
Speaker 1: information in the same image. Yeah, and it's just another
23:06
Speaker 1: way to mathematically express things. And this concept invented by
23:10
Speaker 1: one Maldasena is called a D S c F T
23:13
Speaker 1: because it shows us how one set of theories a
23:15
Speaker 1: d S which means anti disit or space, which is
23:18
Speaker 1: what gravity works in, is really equivalent to these conformal
23:22
Speaker 1: field theories which operate in two dimensional space. And so
23:25
Speaker 1: you're right, it's a trick, but it's also it's a
23:27
Speaker 1: cool trick because it shows us that two totally different
23:30
Speaker 1: fields are actually have been doing the same thing the
23:32
Speaker 1: whole time. That three D movies are really just movies, right,
23:36
Speaker 1: And so the days and maybe our entire universe that
23:39
Speaker 1: we think is three D is actually only two D.
23:43
Speaker 1: Like maybe we're all living on the surface of a
23:45
Speaker 1: black hole or something. Yeah, maybe our universe actually is
23:48
Speaker 1: only two dimensions, and we have this experience of a
23:51
Speaker 1: third dimension because of the richness of the quantum fields
23:54
Speaker 1: gives the illusion of a third dimension. That's the hologram. Right,
23:58
Speaker 1: So that's a fun idea, and it helps think about
24:00
Speaker 1: how to solve black holes and construct string theories, and
24:03
Speaker 1: goes to fund philosophical arguments about like, well, what does
24:06
Speaker 1: it really mean to have three dimensions or two plus
24:08
Speaker 1: one illusory dimensions? But you know, if that's the case,
24:11
Speaker 1: that would mean that fundamentally the whole universe really is
24:14
Speaker 1: two D. Yeah, we're all inside a comic book, right,
24:17
Speaker 1: It's like everything in the universe is a two D
24:20
Speaker 1: object in that case, right, Yeah, And the comic book
24:23
Speaker 1: is really an excellent example because what do you do
24:25
Speaker 1: when you look at the comic book is you don't
24:27
Speaker 1: just examine the two D surface of the paper. You
24:30
Speaker 1: imagine a whole rich world in your mind. You know,
24:32
Speaker 1: a well drawn comic creates into the mind of the
24:35
Speaker 1: reader this whole three dimensional model. And that's exactly what
24:39
Speaker 1: we're talking about here, is having enough information on a
24:41
Speaker 1: two D surface to project out into a fully realized
24:45
Speaker 1: three D world. Well, I called DIBs and being Superman
24:48
Speaker 1: in this comic book, all right, I called DIBs on
24:51
Speaker 1: all those super thin slices of pizza in your comic book.
24:53
Speaker 1: Have at it. I'd rather fly than although if you're
24:56
Speaker 1: flying a comic book, you're you're really not going anywhere.
24:59
Speaker 1: Does that count as exercise? When Superman flies? Does he
25:01
Speaker 1: burning calories? Does his fit bit counter? Well? I think
25:04
Speaker 1: he can't fly if he doesn't get enough sun, So
25:07
Speaker 1: technically I guess he is expending energy. Is that right?
25:09
Speaker 1: He can't fly but it doesn't get enough sun. Does
25:11
Speaker 1: he photosynthesize? Yeah? Don't you know anything about Superman, Daniel,
25:14
Speaker 1: about the physics of Superman? Apparently I don't. He gets
25:18
Speaker 1: his power from the yellow sun. Where so he's basically
25:21
Speaker 1: a plan basically a super solar cell. Yeah, solar battery.
25:26
Speaker 1: All right, Well, so that's one kind of two dimensional object.
25:29
Speaker 1: Is this idea that the whole world is universe is
25:32
Speaker 1: two dimensional? But there are all some ways in which
25:34
Speaker 1: the theory says that you can't have kind of two
25:36
Speaker 1: dimensional things in our three D world, right, Yeah, And
25:40
Speaker 1: earlier we were talking about building things which are the
25:43
Speaker 1: thinnest they could possibly be in a quantum universe. Idea
25:47
Speaker 1: there is that the universe we don't think is infinitely dividable.
25:50
Speaker 1: We don't think you can take a mile and cut
25:52
Speaker 1: in half and then cut it half again, and cutn't
25:54
Speaker 1: half again, and keep doing that forever. We think that
25:57
Speaker 1: probably there's a smallest unit of distance, below which it
26:01
Speaker 1: doesn't make any sense to talk about distance, because there's
26:04
Speaker 1: no measure that's smaller than that. It's like pixels on
26:07
Speaker 1: the screen. And so the idea is, if the universe
26:10
Speaker 1: is quantized, if there's a minimum distance, then like a
26:14
Speaker 1: sheet of something, which is the thinnest possible sheet, might
26:18
Speaker 1: effectively be a two D material. The problem is that
26:21
Speaker 1: we think that distance, if it exists, is probably really
26:24
Speaker 1: really small, like ten to the minus thirty five, and
26:28
Speaker 1: we're certainly not capable of making anything or observing anything
26:32
Speaker 1: that thin today. But quantum mechanics has other implications. You know,
26:36
Speaker 1: quantum mechanics limits how particles can move. Another idea, which
26:40
Speaker 1: has been around for several decades, is to make something
26:42
Speaker 1: that's so thin that it's thinner than the wavelength of
26:45
Speaker 1: the electrons, so that the electrons in that object are
26:49
Speaker 1: essentially trapped to only move in two dimensions because the
26:52
Speaker 1: thing they're stuck in doesn't allow them to get excited
26:55
Speaker 1: or move in that third dimension. I see, I feel
26:57
Speaker 1: like there's two ideas here. One is making things small
27:00
Speaker 1: holler than the smallest resolution of the universe, and the
27:04
Speaker 1: other one is making things smaller than the electron wave length.
27:08
Speaker 1: So which one are Are they the same or which
27:10
Speaker 1: one are you talking about here? They're not the same.
27:13
Speaker 1: One is very fundamental like to the nature of space
27:15
Speaker 1: and time, and just sort of to get you thinking
27:17
Speaker 1: about how the universe really is quantized. How there's like
27:21
Speaker 1: units of thinness, and the thinnest unit for space is
27:25
Speaker 1: really really really thin, but the thinnest unifer an electron,
27:28
Speaker 1: is much much larger, and something that's really kind of
27:30
Speaker 1: achievable because an electron has an extent in space which
27:34
Speaker 1: is much more significant. So you know, can you build
27:37
Speaker 1: something which makes it so that electrons can only move
27:40
Speaker 1: in two dimensions? That could be much much bigger than
27:43
Speaker 1: the fundamental unit of space. I mean imagine, for example,
27:46
Speaker 1: taking two sheets of glass and putting ping pong balls
27:49
Speaker 1: between them, and the ping pong balls can move between
27:51
Speaker 1: the sheets of glass, but they can't move up and
27:54
Speaker 1: down at all. If you could build a material like
27:56
Speaker 1: that where the electrons only move in two dimensions, then
27:59
Speaker 1: you might cansider that to be a two dimensional material.
28:02
Speaker 1: I guess the hard question is what is the object? Like,
28:05
Speaker 1: are the electrons the object or the thin sheet is
28:08
Speaker 1: the object? Because the sheet itself isn't made out of
28:12
Speaker 1: multiple layers of atoms. Are you talking about making something
28:15
Speaker 1: that's just one layer of atoms? So the basic idea
28:17
Speaker 1: is to make something which is a single layer of atoms.
28:20
Speaker 1: It's a lot like what we were talking about earlier.
28:22
Speaker 1: We take a single cork and you line it up
28:24
Speaker 1: and you make a sheet of corks. If you could
28:26
Speaker 1: get these things which bind together and to make a
28:29
Speaker 1: single layer of atoms, like a material that's just one
28:32
Speaker 1: atomic layer thick, then the electrons in that material would
28:37
Speaker 1: move as if they were in a two dimensional world.
28:40
Speaker 1: I see. So then you're saying like kind of like
28:42
Speaker 1: that collection of electrons is then sort of a two
28:45
Speaker 1: D object because it can't really, you know, move in
28:49
Speaker 1: any other dimension except the one on the surface. Yeah,
28:52
Speaker 1: because there's no room for them to move, like ping
28:54
Speaker 1: pong balls trapped between two sheets of glass. Electrons are
28:58
Speaker 1: bound to the atoms, and if there's no layer up
29:01
Speaker 1: or layer down for them to go, then they're sort
29:03
Speaker 1: of trapped on that sheet. So that's pretty cool. Is
29:06
Speaker 1: it hard to make something like that, like to make
29:08
Speaker 1: a sheet that's only one atom thick. It turns out
29:11
Speaker 1: it's surprisingly easy and you probably make them all the
29:14
Speaker 1: time when you draw cartoons. Really, are you saying my
29:17
Speaker 1: ideas have no no? It turns out that you make them.
29:23
Speaker 1: Every time you sharpen a pencil. You make a two
29:25
Speaker 1: dimensional material. Because carbon is a really amazing object, and
29:30
Speaker 1: you can form all sorts of really crazy stuff. And
29:32
Speaker 1: it is possible to make sheets of carbon that are
29:35
Speaker 1: just one atom thick. And one way to do it
29:38
Speaker 1: is to break off pieces of basically graphite, which is
29:41
Speaker 1: pencil lead. And graphite is so brittle that basically every
29:44
Speaker 1: time you write on a surface of paper or you
29:46
Speaker 1: sharpen your pencil, you are generating these sheets of graphine
29:50
Speaker 1: just things. So like carbon kind of likes to do that, right,
29:53
Speaker 1: like it, It kind of likes to arrange itself in
29:56
Speaker 1: little sheets and not like cubes or clusters. It likes
29:59
Speaker 1: to do all sorts of things, and so you have
30:01
Speaker 1: to get it to do this. But graphite exactly is
30:04
Speaker 1: very brittle, and so it's not that hard to like
30:06
Speaker 1: peel off layers of it to make these two dimensional
30:10
Speaker 1: sheets of carbon. And so I thought this was super interesting,
30:13
Speaker 1: and I went to ask a friend of mine, who's
30:15
Speaker 1: actually a professor here at u C Irvine, is this
30:18
Speaker 1: is possible, what it really means, and what she thinks
30:21
Speaker 1: about two dimensional materials? Nice? Who did you talk to? So?
30:24
Speaker 1: I talked to a young assistant professor named Judy Rohani.
30:28
Speaker 1: She's very friendly. She's from Hungary and she just came
30:30
Speaker 1: to u C I about a year and a half ago,
30:32
Speaker 1: and she arrived during the pandemic, which means she's never
30:35
Speaker 1: really gone to experience the campus life here. Wow. And
30:38
Speaker 1: so she works on these two de materials, right. She
30:41
Speaker 1: makes these flat sheets of carbon and then she puts
30:44
Speaker 1: electrons in them, and then the electrons sort of move
30:46
Speaker 1: around in this one dimensional world. Yeah. She's actually a theorist,
30:50
Speaker 1: so she mostly like writes papers about them and thinks
30:52
Speaker 1: about them rather than actually building these things. But yeah,
30:55
Speaker 1: she's a pretty deep understanding of how they work. All right.
30:57
Speaker 1: So you asked her to talk to us about some
30:59
Speaker 1: of the materials. Yeah. I asked her if she thought
31:02
Speaker 1: two dimensional materials were possible and what it meant for
31:05
Speaker 1: an object to be two dimensional? All right? Here is
31:08
Speaker 1: what Professor Roney had to say, So, you know what,
31:11
Speaker 1: like for theories, anything is possible, right because I just
31:15
Speaker 1: take a TI to come on and then say like, well,
31:17
Speaker 1: I just considered something that has two spatial demensions dimensions
31:21
Speaker 1: instead of three, and that will give me some kind
31:24
Speaker 1: of confinement. So you know, my mobile particles for examples,
31:28
Speaker 1: like electrons, they can only move in two dimensions, but
31:31
Speaker 1: not in the third dimension. And then then it comes
31:34
Speaker 1: like real life, you know, like I have a real
31:36
Speaker 1: chunk of material that definitely has extensions in all three dimensions, right,
31:41
Speaker 1: So that's very different. It's like I guess if you
31:44
Speaker 1: ask this question like fifteen years ago, I was just like, yeah,
31:48
Speaker 1: today is very theoretical. There is no such thing as
31:52
Speaker 1: a two de material, right because why would it not
31:55
Speaker 1: like fold up like that, you know, why wouldn't stay
31:59
Speaker 1: like straight as a sheet of paper or something, or
32:01
Speaker 1: how could it exist, like what would stabilize anything like that?
32:04
Speaker 1: And now it turns out that that there are actually
32:06
Speaker 1: two dimensional materials, and then what those are kind of
32:10
Speaker 1: like if you imagine that you have a material that
32:13
Speaker 1: is say like one automn thick or maybe maybe still
32:17
Speaker 1: it's a better way to say, or maybe just a
32:20
Speaker 1: few atoms in, like maybe two or three atoms in,
32:23
Speaker 1: and that's that's actually possible to create these materials. So
32:26
Speaker 1: actually kind of bail them off from their three dimensional
32:30
Speaker 1: let's say modern material or different types of materials. They
32:35
Speaker 1: really exist and people are doing different kinds of experiments
32:38
Speaker 1: and so it's not just you know, theoretical dream anymore.
32:42
Speaker 1: It's actually an existing thing, which is very exciting because
32:45
Speaker 1: they do have a lot of dissimilarities to see the
32:49
Speaker 1: action three D models or materials. All right, I like it,
32:53
Speaker 1: As she said, for a theorist, anything is possible. I
32:57
Speaker 1: think I really tells you something about this field. This
33:00
Speaker 1: is an idea which came about like in the forties
33:03
Speaker 1: and fifties. People were wondering is this really possible? They
33:06
Speaker 1: were thinking about it and theorizing about it, and only recently,
33:09
Speaker 1: only like twenty years ago, did this actually become realizable.
33:13
Speaker 1: So this is something it's sort of like the black
33:15
Speaker 1: holes for condensed matter physics. They're wondering, mathematically, we figured
33:18
Speaker 1: this out, but could anybody actually make this thing in
33:21
Speaker 1: real life? So I think we're sort of living in
33:24
Speaker 1: the science fiction future for a lot of these condensed
33:26
Speaker 1: matter physicists. That's pretty cool. And she says that, you know,
33:29
Speaker 1: if you do confine electrons into one of these thin materials,
33:33
Speaker 1: they do sort of actually kind of move like in
33:35
Speaker 1: a two D world. Yeah, and it makes the thing
33:37
Speaker 1: really really different. And that's what's really interesting. If that
33:40
Speaker 1: if you take a whole loaf of bread and you
33:41
Speaker 1: cut in half, you have half a loaf of bread. Right,
33:44
Speaker 1: But at some point if you take really really thin slices,
33:47
Speaker 1: it stops being bread and it starts turning into something else. Right,
33:51
Speaker 1: it turns into toast that's totally different bread or biscotti.
33:55
Speaker 1: It turns into biscotty. You know, you have to pay
33:57
Speaker 1: like a few bucks more starbucks, get put tomato, sauce
34:01
Speaker 1: and cheese on, and poor he will call it a pizza.
34:03
Speaker 1: But I think it's really cool that you take something
34:06
Speaker 1: and you make a thin enough slice that it basically
34:08
Speaker 1: turns into something else. Like imagine taking a loaf of
34:11
Speaker 1: bread and making it such a thin slice that you
34:13
Speaker 1: get a slice of ham, you know, or it turns
34:15
Speaker 1: into cheese or something. That's basically what's happening here. You
34:18
Speaker 1: take graphite, which is you know, this like thing inside
34:21
Speaker 1: pencil lead and you take such a thin slice off
34:24
Speaker 1: of it that it comes off with completely different properties,
34:27
Speaker 1: totally different sort of mechanical strength and electrical properties and
34:31
Speaker 1: all that stuff. Wow, that sounds like delicious magic right there.
34:35
Speaker 1: All right, so those are theoretical to the objects, and
34:38
Speaker 1: so now let's get into real to the objects. Are
34:42
Speaker 1: any of these actually realizable in our world? And maybe
34:46
Speaker 1: they're all around this, So let's get into that. But
34:48
Speaker 1: first let's take another quick break. All right, Daniel, we're
35:03
Speaker 1: talking about real life to the objects. Now we talked
35:07
Speaker 1: about in theory. It could be that we're all in
35:09
Speaker 1: the to the world, or maybe you can make electrons
35:12
Speaker 1: behave like they're in two dimensionals. But in the real
35:15
Speaker 1: world that we live in, at least that the one
35:17
Speaker 1: that seems like it's three dimensions, can you have to
35:20
Speaker 1: the objects? So you sort of can, I mean it's
35:22
Speaker 1: a little bit cheating. They're not technically two dimensions because
35:26
Speaker 1: the materials themselves do have a height. But the mathematics
35:29
Speaker 1: on these materials is the same as if they were
35:32
Speaker 1: two dimensions. Like if the world was two dimensional, mathematics
35:36
Speaker 1: and physics especially would be different. For example, we know
35:39
Speaker 1: that if you shine a light, then the strength of
35:41
Speaker 1: that light decreases like one over the distance squared. That's
35:45
Speaker 1: one of the distance squared. Because our universe is in
35:48
Speaker 1: three dimensions. The same amount of light spread over the
35:51
Speaker 1: surface of a sphere, and the surface of a sphere
35:54
Speaker 1: goes like the radius squared. So there's things like that
35:58
Speaker 1: where mathematical relationships tell you about the dimensionality of the
36:02
Speaker 1: world you're living in. And when we study the behavior
36:04
Speaker 1: on some of these physical materials we're gonna be talking about,
36:07
Speaker 1: we see the mathematical relationships you expect from a two
36:10
Speaker 1: dimensional world, not a three dimensional world. I see. So
36:13
Speaker 1: there are like three D objects that behave or you know,
36:16
Speaker 1: follow the rules of a two dimensional universe, Yes, exactly.
36:20
Speaker 1: And so in the sense if you're following the math
36:21
Speaker 1: of a two dimensional world, are you really a two
36:24
Speaker 1: D object? Interesting like if you do live in a cartoon?
36:28
Speaker 1: Are you really real? If you cosplay enough a cartoon,
36:32
Speaker 1: are you really in that cartoon? No judging, no judging.
36:36
Speaker 1: So to step us through, what are some of these
36:38
Speaker 1: real life to the objects or three the objects that
36:41
Speaker 1: behave like to the objects, So one of them is
36:43
Speaker 1: looking at the surface of liquid helium, liquid Helium, of course,
36:47
Speaker 1: is helium that's super duper duper cold so that it
36:49
Speaker 1: turns into a liquid, and if you drop electrons onto
36:52
Speaker 1: liquid helium, then they like to stick to the surface.
36:56
Speaker 1: Like liquid helium is this really weird surface tension, and
36:58
Speaker 1: electrons like to stick to the surface, but they're free
37:01
Speaker 1: to slide along it because liquid helium is super fluid,
37:04
Speaker 1: so electrons can slide along it really easily, but they're
37:06
Speaker 1: stuck on the surface. And of course the surface of
37:09
Speaker 1: an object is two dimensional, and so these electrons are
37:12
Speaker 1: confined to the surface, but they can slide around. So
37:15
Speaker 1: it's really a lot like those ping pong balls stuck
37:18
Speaker 1: between two glass planes. And so this is something people
37:21
Speaker 1: can actually build. And they call this a two dimensional
37:24
Speaker 1: electron gas, not a gas, because it's like something you
37:27
Speaker 1: can breathe. But these are just sort of like idealized
37:29
Speaker 1: particles bouncing around and moving, and it follows the laws
37:34
Speaker 1: of thermodynamics in two dimensions. It's almost like just having
37:37
Speaker 1: things on balls on the table, right like it they're
37:39
Speaker 1: just sitting on the surface of the ping pong table
37:42
Speaker 1: and they sort of roll around, but they can't just
37:45
Speaker 1: jump off, right, But if they bounced into each other,
37:48
Speaker 1: then they would sometimes leave the surface. You can get
37:50
Speaker 1: that sort of excitation in the third dimension. But if
37:53
Speaker 1: they're trapped, if there really are confined you have like
37:55
Speaker 1: a layer of glass over your ping pong table, then
37:58
Speaker 1: they really are trapped in there, and the only way
38:00
Speaker 1: they can move is in two dimensions. And I see,
38:01
Speaker 1: so the electrons are sort of stuck to the surface
38:04
Speaker 1: of the liquid helium. Yeah, it's some weird chemistry thing
38:07
Speaker 1: where they are stuck to the service of the liquid helium.
38:09
Speaker 1: And like how you say it's some weird chemistry thing
38:12
Speaker 1: and you don't have a good answer. That means I
38:14
Speaker 1: don't understand it. I'm not a chemist. All the chemistry
38:17
Speaker 1: is some weird chemistry thing to be all right. So
38:20
Speaker 1: that's one kind of two D pseudo object. What are
38:23
Speaker 1: some other kinds? The most interesting, and I think the
38:25
Speaker 1: most exciting is this thing called graph being graphing is
38:29
Speaker 1: a two D sheet of carbon atoms that assemble themselves
38:33
Speaker 1: into an object. You know that carbon can make lots
38:36
Speaker 1: of different things. It can make diamond, you can make graphite,
38:38
Speaker 1: which is basically coal, but it can also make all
38:41
Speaker 1: sorts of other things. And I love carbon and all
38:43
Speaker 1: of its forms, because it really makes a point which
38:46
Speaker 1: I think is really deeply true about the universe, which
38:48
Speaker 1: is that the nature of an object is not about
38:50
Speaker 1: what it's made out of, but about how those things
38:53
Speaker 1: are put together. So you can put the same carbon
38:55
Speaker 1: atoms together to make a diamond or a lump of coal,
38:58
Speaker 1: and that really tells you that it's really just some
39:00
Speaker 1: out how you build the thing, and there's a really
39:02
Speaker 1: weird and unique way that you can build it to
39:04
Speaker 1: make this single atomic layer of carbon atoms, and they
39:08
Speaker 1: call that graphene. Yeah, and that was the Nobel Prize
39:11
Speaker 1: maybe like ten or fifteen years ago, right where they
39:13
Speaker 1: discovered it by using scotch tape on a pencil lead shavings. Yeah,
39:18
Speaker 1: in two thousand and ten. They won the Nobel Prize
39:21
Speaker 1: for an experiment they published in two thousand four. And
39:24
Speaker 1: these are two folks in the UK that, as you say,
39:27
Speaker 1: you scotch tape, they took like pieces of graphite and
39:30
Speaker 1: they realized that if you get scotch tape on the
39:32
Speaker 1: graphite and you pull it away, you get thinner pieces
39:35
Speaker 1: of graphite, sometimes very very thin. And then they would
39:38
Speaker 1: pride these pieces of scotch tape open, and they would
39:41
Speaker 1: do it again and again and again until they got
39:44
Speaker 1: mono layers of graphite, which they called graphine. Right, it's
39:48
Speaker 1: like you create like a sheet of single carbon atoms. Yeah,
39:52
Speaker 1: a sheet of single carbon atoms. Now in your mind
39:55
Speaker 1: you might be imagining like that they're rolling out some
39:57
Speaker 1: huge roll of this stuff that's like ten by ten meters.
40:00
Speaker 1: What they were able to do in their first paper
40:02
Speaker 1: were pieces of graphing that were ten microns in size.
40:06
Speaker 1: That's still pretty big. I mean it's like, you know,
40:09
Speaker 1: maybe a couple of hundred adams in each side. Absolutely,
40:13
Speaker 1: so it's pretty impressive. And they had some bigger pieces
40:15
Speaker 1: that you could see by I they weren't actually down
40:17
Speaker 1: to one atomic layer. There were like several atomic layers.
40:20
Speaker 1: This is not a very precise method. You know, scotch
40:23
Speaker 1: tape on pencil shavings essentially, I mean, it's not like
40:26
Speaker 1: duct tape. If you used duct tape, then then you're
40:28
Speaker 1: really doing real physics. I would guess that every Experimental
40:31
Speaker 1: physics Nobel Prize since duct tape was invented has had
40:34
Speaker 1: duct tapes somewhere in their experience. That Mr Duck should
40:37
Speaker 1: get his own prize in engineering somewhere. But it also
40:41
Speaker 1: means that we've probably all been generating sheets of graphing
40:44
Speaker 1: every time we've used pencils, because this stuff really is
40:47
Speaker 1: so riddle. You get these little sheets of graphing, these
40:50
Speaker 1: two dimensional materials falling off of your pencils. Yeah, and
40:54
Speaker 1: graphing is interesting because it's not just like flat, almost
40:57
Speaker 1: two dimensional, but it has some pretty using properties. Right.
41:01
Speaker 1: It's really an incredibly different kind of stuff than graphite.
41:05
Speaker 1: You know, graphite, this stuff in your pencil not very strong, right,
41:08
Speaker 1: You wouldn't want to build like a sheet of armor
41:10
Speaker 1: out of this stuff. But graphene is two hundred times
41:13
Speaker 1: stronger than steel by weight, and it's like a sheet
41:17
Speaker 1: of it is a thousand times lighter than a sheet
41:20
Speaker 1: of paper. What does that mean? Stronger? Like, if you
41:21
Speaker 1: pull in it or try to poke through it, it
41:23
Speaker 1: will be stronger than if you made it out of steel.
41:27
Speaker 1: You can support the weight, so you can hang something
41:29
Speaker 1: from it, for example, or build things out of it.
41:31
Speaker 1: It's stronger than steel. You could, for example, make a
41:34
Speaker 1: hammock that's so thin it would be invisible, and the
41:38
Speaker 1: cat could sit on the hammock and be like floating
41:40
Speaker 1: in air cool and it also has interesting electrical properties. Right,
41:44
Speaker 1: It's really an incredible material because it has the most
41:46
Speaker 1: electrical and thermal conductivity of any material we know about
41:50
Speaker 1: at room temperature. So it's like the strongest, lightest, most
41:55
Speaker 1: electrically conductive, most thermally conductive material basically we've ever discovered it.
42:00
Speaker 1: Now is the idea then to make like computer chips
42:02
Speaker 1: out of it, Like instead of using silicon and you know,
42:06
Speaker 1: doping in and printing it, you could maybe draw it
42:09
Speaker 1: using graphing. That was the original idea because we know
42:12
Speaker 1: that chips need to get smaller and smaller for computers
42:15
Speaker 1: to get faster and faster. But we're sort of approaching
42:17
Speaker 1: the limit of what semiconductors can do, and it's really
42:21
Speaker 1: hard to imagine making things that are smaller out of metal.
42:25
Speaker 1: So these guys achieved creating a material which is electrically
42:29
Speaker 1: conductive and so can be used to form these chips
42:32
Speaker 1: and is super duper narrow. So that's exactly what people
42:35
Speaker 1: are working on applications of graphing to do electronics and
42:38
Speaker 1: computer chips, but also construction, you know, making things out
42:42
Speaker 1: of this new kind of material, Right, like you can
42:44
Speaker 1: maybe stack these sheets and make super strong body armor
42:48
Speaker 1: basically or anything, right the house. Yeah, and you get
42:51
Speaker 1: really weird properties, like you can make sheets of graphing,
42:53
Speaker 1: but there are also other kinds of materials you can
42:56
Speaker 1: now make model layers of and you take one sheet
42:59
Speaker 1: of graphing as sheet of something else, and you can
43:01
Speaker 1: make these weird structures they're called hetero structures that now
43:04
Speaker 1: have other really strange properties. And so because these are
43:08
Speaker 1: weird two D materials, you can stack them together to
43:10
Speaker 1: make three D sort of like designer materials. You can
43:14
Speaker 1: make materials that are totally different from anything we've been
43:17
Speaker 1: able to make before. So it's opened up this whole
43:19
Speaker 1: new field of like engineering new kinds of materials. So
43:23
Speaker 1: you can build a house and then you can let
43:24
Speaker 1: your kids draw in it with a pencil and it'd
43:26
Speaker 1: be totally acceptable. Right, You're like, I have nothing, I
43:31
Speaker 1: have nothing for that. All right, that's a cartoonist dream house,
43:35
Speaker 1: it sounds like to me. All right. So then you
43:37
Speaker 1: can also make these two D materials using quasi particles,
43:41
Speaker 1: which I know we talked about before, but maybe we
43:43
Speaker 1: didn't talk about the two dimensionality of them. Yeah, quasi particles. Remember,
43:47
Speaker 1: our things are not particles in the way that we
43:49
Speaker 1: think about them, but mathematically they follow the same rules
43:53
Speaker 1: as particles. And so the way I think about it
43:55
Speaker 1: is like, well, a particle is a little excited blob
43:58
Speaker 1: of energy and a quantum field. You can also have
44:01
Speaker 1: excited blobs of energy and other stuff that stays sort
44:04
Speaker 1: of localized and moves around, and so sort of follows
44:07
Speaker 1: the same math that we use to consider particles. And
44:11
Speaker 1: the kind of thing you can deposit energy into is
44:13
Speaker 1: like a sheet of plasma. You know. Plasma is this
44:16
Speaker 1: fourth state of matter where you heat up stuff hot
44:19
Speaker 1: enough that the electrons go free, and you have this
44:22
Speaker 1: basically gas of charged particles. Like what's in the sun
44:26
Speaker 1: is plasma or what's in your fluorescent light tumbe is plasma.
44:29
Speaker 1: Plasma because it's charged and has lots of really strong
44:32
Speaker 1: electromagnetic forces, and so sometimes it forms these sheets, you know,
44:36
Speaker 1: it's like separates into sheets, a positive sheet in a
44:38
Speaker 1: negative sheet, and those sheets can have excited states. Sometimes
44:43
Speaker 1: like ripples go through those sheets and they act like particles.
44:46
Speaker 1: So that's a quasi particle that's called an en eon. Yeah,
44:50
Speaker 1: and I know what's kind of exciting about these materials
44:52
Speaker 1: is their application in things like quantum computers, right, and
44:56
Speaker 1: encryption and making things that are sort of full proof
44:59
Speaker 1: against quantum decoherence. There are certainly applications in quantum computers
45:03
Speaker 1: for some quasi particles. I think that for me, the
45:06
Speaker 1: exciting thing about them is that they follow rules of
45:09
Speaker 1: a different universe. They follow the rules of a two
45:12
Speaker 1: dimensional universe, like the mathematical rules the things we're talking
45:16
Speaker 1: about very early in the top of the program, like
45:18
Speaker 1: why is our universe three D and not four D?
45:20
Speaker 1: And what would it be like? We can sort of
45:22
Speaker 1: see what a two D universe really would be like,
45:25
Speaker 1: and we have the math to describe it. But now
45:27
Speaker 1: we actually get to see the physics of it, and
45:29
Speaker 1: you might wonder, like, well, what would it do D
45:31
Speaker 1: universe be? Like? How could that be different? You know,
45:34
Speaker 1: in a two dimensional universe there's a different relationship, for example, right,
45:37
Speaker 1: between energy and velocity. Like in our universe energy is
45:41
Speaker 1: one half MV squared, right, there's a V squared there,
45:44
Speaker 1: But in a two dimensional universe it's not V squared.
45:47
Speaker 1: There's a linear relationship between energy and velocity. So that's
45:50
Speaker 1: the kind of mathematical difference. You get like different kind
45:53
Speaker 1: of physics in these two d universes, and so you
45:56
Speaker 1: can see that happening in these examples. And it's especially
46:00
Speaker 1: weird for an eons is that they follow different spin statistics.
46:05
Speaker 1: Like we have particles in our universe that are either
46:08
Speaker 1: fermions or bosons, and fermions don't like to exist in
46:12
Speaker 1: the same quantum state, whereas bosons are happy to hang
46:15
Speaker 1: out in the same quantum state. Well, anyons can be
46:19
Speaker 1: somewhere between fermions and bosons. They're not like fermions exactly,
46:23
Speaker 1: They're not like boson's exactly. They're like has sort of
46:26
Speaker 1: like fractional in between states. Cool, you'd have to start
46:29
Speaker 1: a whole new field called cartoon physics basically, right, Like
46:33
Speaker 1: it's a whole new and different, whole new ball game,
46:36
Speaker 1: whole new comic book. It's a whole new ball game
46:38
Speaker 1: and a whole new way to like explore the universe
46:40
Speaker 1: and see weird stuff and to get surprised. Well, it
46:43
Speaker 1: sounds pretty cool. It sounds like to the objects are
46:46
Speaker 1: not just as possible and theoretical, but they're also right
46:49
Speaker 1: here in our universe. You can make them. You can
46:52
Speaker 1: create them, you can sandwich them, you can make pizzas
46:54
Speaker 1: out of them, put entovies on them, and so that
46:58
Speaker 1: opens things up to a lot of interesting new math
47:01
Speaker 1: and maybe a whole bunch of new materials. And so
47:03
Speaker 1: to have the last word, we'll bring back Professor Rohani
47:07
Speaker 1: to tell us a little bit about the future of
47:09
Speaker 1: these new and exciting materials. Oh. I think there is
47:12
Speaker 1: a lot of research already in experiment even as you
47:15
Speaker 1: see I I and a lot of researching different two
47:19
Speaker 1: dimensional materials. Graphin is not the only one. There are
47:22
Speaker 1: materials so cood, wonderbos materials, and these are layer materials
47:28
Speaker 1: that you can imagine as very similar to the graphite
47:31
Speaker 1: of which you can peel off the grappin, so you
47:33
Speaker 1: have very weakly connected layers and that you can just
47:37
Speaker 1: build the layers of these materials. And what people can
47:41
Speaker 1: do with them is kind of engineer the band structure
47:44
Speaker 1: and therefore together with that engineer physical properties of material
47:48
Speaker 1: and create new type of material with completely new physical
47:51
Speaker 1: properties just by putting these layers on top of each other,
47:55
Speaker 1: like making making a sandwich or something of them. They're
47:59
Speaker 1: doing ex ments are using orso graphine and hexagonal born
48:03
Speaker 1: n trade and other condropost materials. And I think the
48:07
Speaker 1: transition method that could janites I can pronounce that the
48:11
Speaker 1: perfectly yes, that you can use to build these different
48:16
Speaker 1: kind of so called hetero structures when you just leave
48:18
Speaker 1: your you know, these different two dimensional materials on top
48:22
Speaker 1: of each other and then create new types of materials
48:25
Speaker 1: and you know, examine, how do I change the physical properties?
48:30
Speaker 1: Can I make a superconductor or can I make out
48:33
Speaker 1: of you know, like I have graphine, which is insanely
48:35
Speaker 1: good conductor, but if I leave you and maybe the
48:38
Speaker 1: becompany insulator and so on. So you know, all of
48:42
Speaker 1: discussions and I think it's very nice because it's kind
48:44
Speaker 1: of playground and you can build so many things with
48:49
Speaker 1: this and not just you know, I kind of try
48:51
Speaker 1: to engineer and make functional materials that you can then
48:56
Speaker 1: use in applications for you know, the semi conductor business,
48:59
Speaker 1: which is huge, right, so you can just make you know,
49:01
Speaker 1: faster for more efficient chips and stuff like that, but
49:05
Speaker 1: also completely new technologies. And I think a lot of
49:09
Speaker 1: research has already put in the in the past I
49:11
Speaker 1: think ten fifteen years. So you can take bread slices
49:15
Speaker 1: and slices and then rebuild it in different slices to
49:18
Speaker 1: make whatever you like, to make all sorts of new stuff. Yeah,
49:22
Speaker 1: synthetic materials. Yeah. Like think you take a slice of
49:25
Speaker 1: bread which is not a bread anymore. It is completely different,
49:28
Speaker 1: and then you put some ham on it, and it's
49:30
Speaker 1: not a sandwich. Is just something entirely different. You know,
49:32
Speaker 1: it's likely So it's insane. All right. That was a
49:35
Speaker 1: deep dive into some to the ideas. Sounds like the
49:39
Speaker 1: future is bright for these two D objects. Yeah, and
49:42
Speaker 1: people are just now thinking about even crazier ideas, like mathematically,
49:46
Speaker 1: can you have a one D object? Can you construct
49:48
Speaker 1: an object that's just a string of atoms that are
49:51
Speaker 1: somehow bound together? What would be the properties of that
49:54
Speaker 1: kind of thing? How could you make it? Could you
49:56
Speaker 1: like take graphine and somehow like slice it off using
49:59
Speaker 1: two the Scotch tape to make one D strings? Is
50:02
Speaker 1: that the next Nobel Prize? Oh? Man, I feel like
50:05
Speaker 1: you should take it easy and just maybe go one
50:07
Speaker 1: and a half D first, you know what I mean?
50:10
Speaker 1: Like that's crazy. Hey, Well, my wife says I'm too dimensional,
50:14
Speaker 1: so I gotta mechanic go on a diet exactly. But
50:17
Speaker 1: until then we can have fun thinking about these things,
50:19
Speaker 1: wondering what the math is like in a one dimensional universe,
50:22
Speaker 1: and maybe one day somebody will build a one D
50:25
Speaker 1: object and we can actually see how electrons move along
50:28
Speaker 1: it in one dimension. You just you have to look
50:30
Speaker 1: at it from the side. You can't look at it
50:31
Speaker 1: hit on. All right, Well, we hope you enjoyed that.
50:34
Speaker 1: Thanks for joining us, see you next time. Thanks for listening,
50:45
Speaker 1: and remember that Daniel and Jorge explained. The Universe is
50:48
Speaker 1: a production of I Heart Radio or more podcast from
50:51
Speaker 1: my heart Radio. Visit the I Heart Radio Apple Apple Podcasts,
50:55
Speaker 1: or wherever you listen to your favorite shows.