Latest / The Quark Side - Quantum Physics Podcast / Emergent Topology Beyond the Particle Picture

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Emergent Topology Beyond the Particle Picture · The Quark Side - Quantum Physics Podcast

0:01
Speaker 1: Welcome to the quart Side Quantum Physics Podcast, an exploration
0:05
Speaker 1: of the fundamental structure of reality, where quantum laws govern matter, energy,
0:11
Speaker 1: and information. Here, uncertainty is a feature, not a flaw,
0:16
Speaker 1: and understanding begins with the smallest scales.
0:27
Speaker 2: Welcome back. We are getting into something today that I
0:30
Speaker 2: genuinely think is going to change the way you look
0:35
Speaker 2: at the world. And I don't mean that in a
0:37
Speaker 2: spiritual journey kind of sense, though it does get pretty.
0:39
Speaker 3: Close, it gets weirdly close.
0:41
Speaker 2: Yeah, I mean it in the literal physical sense of
0:44
Speaker 2: looking at a table or a wall or your own
0:47
Speaker 2: hand and just questioning what is what is actually there?
0:52
Speaker 3: It's a fundamental shift. I mean usually when we talk
0:54
Speaker 3: about science news, it's a faster chip, or a better battery,
0:57
Speaker 3: or a new species of frog, a new species of
0:59
Speaker 3: frog exactly. We're adding to the library of things we know.
1:03
Speaker 3: But today we're talking about rewriting the I don't know
1:07
Speaker 3: the preface of.
1:08
Speaker 2: The book, the preface being what is stuff?
1:11
Speaker 3: Essentially, yes, at its very core.
1:13
Speaker 2: Because we're taught a very specific story when we're kids, right,
1:17
Speaker 2: I remember sitting in fifth grade science class and the
1:20
Speaker 2: teacher draws a circle on the chalkboard. Oh yeah. She
1:23
Speaker 2: puts a little dot in the middle of the nucleus
1:25
Speaker 2: and then draws these little orbits around it with other dots,
1:28
Speaker 2: the electrons, the bore model.
1:30
Speaker 3: It's iconic. It's on the side of every science museum.
1:33
Speaker 2: It is, and it's comforting, you know. It tells us
1:35
Speaker 2: that the universe is made of legos, right, tiny hard, distinct,
1:39
Speaker 2: little billiard balls that bounce around and stick together to
1:42
Speaker 2: make well, to make us.
1:44
Speaker 3: It's what we call the particle picture, and it has
1:46
Speaker 3: been the dominant way of thinking about reality for I mean,
1:48
Speaker 3: over one hundred years. It's practical, it's intuitive, and it
1:52
Speaker 3: works for almost everything we do in engineering. It works perfectly.
1:56
Speaker 2: But you are here today to tell me that a
1:58
Speaker 2: team of researchers in Vienna has basically taken a sledgehammer
2:01
Speaker 2: to that lego.
2:02
Speaker 3: Set h that is that's a pretty fair assessment. Yeah.
2:07
Speaker 3: We were looking at a paper that was just published
2:09
Speaker 3: in Nature Physics from t u ween that's the Vienny
2:12
Speaker 3: University of Technology, Okay, and they have discovered a state
2:15
Speaker 3: of matter that, according to that standard particle picture, should
2:19
Speaker 3: be well impossible. Impossible is a big word in physics.
2:23
Speaker 3: Impossible usually just means we haven't found the right math yet.
2:27
Speaker 3: But in this case, the contradiction is it's stark. They
2:31
Speaker 3: found a material that follows very strict geometric rules, what
2:35
Speaker 3: we call topology, but it does so without having any
2:37
Speaker 3: defined particles to actually follow those rules.
2:40
Speaker 2: Okay, hold on, that's the headline that melted my brain
2:42
Speaker 2: when I first read about this geometry without particles. Mm hm.
2:47
Speaker 2: It sounds like saying you have a traffic jam, but
2:49
Speaker 2: there are no cars, or a smile without the cat,
2:51
Speaker 2: the chessure cat. Yes, we are definitely going to get
2:54
Speaker 2: to that analogy because it's absolutely perfect. But before we
2:56
Speaker 2: go down that rabbit hole, let's set the stakes here.
2:58
Speaker 2: This isn't just about, you know, winning an argument in
3:01
Speaker 2: a faculty lounge. Why does this matter to the person
3:04
Speaker 2: listening right now?
3:05
Speaker 3: Because this discovery, I think is the key to the
3:08
Speaker 3: next generation of technology. We are hitting a wall with
3:11
Speaker 3: our current tech. You hear about Moore's law slowing down
3:14
Speaker 3: all the time, Our sensors are reaching their fundamental limits.
3:18
Speaker 3: This discovery, this breakdown of the particle picture, it opens
3:23
Speaker 3: a door to censors that are virtually immune to noise.
3:26
Speaker 3: It opens the path to quantum computers that don't crash
3:29
Speaker 3: when you look at them, funny which they had to do,
3:31
Speaker 3: which they do, and maybe most impressively, it shows us
3:36
Speaker 3: how we could steer electricity without using magnetic fields.
3:40
Speaker 2: Steering electricity without magnets. How is that? Even?
3:43
Speaker 3: It sounds like magic, but it's just advanced geometry.
3:46
Speaker 2: Okay, I'm hooked.
3:47
Speaker 3: Huh.
3:48
Speaker 2: I want to understand how the cars disappeared, but the
3:50
Speaker 2: traffic jam stayed. Let's unpack this. Let's do it so
3:53
Speaker 2: to really understand why this is such a shock, we
3:56
Speaker 2: have to understand what we thought was true. We need
3:59
Speaker 2: to talk about this part picture, or as you called it,
4:01
Speaker 2: the approximation.
4:03
Speaker 3: Right, the useful fiction. So let's take a simple copy
4:06
Speaker 3: wire the cord that's charging your laptop right now. When
4:09
Speaker 3: you think about electricity flowing through that wire, what do
4:12
Speaker 3: you visualize?
4:13
Speaker 2: I picture a tube a highway, and inside that tube
4:17
Speaker 2: there are millions of little glowing balls electrons just racing
4:22
Speaker 2: from the wall socket to my computer.
4:24
Speaker 3: Exactly. You picture them as distinct entities, little spheres. They
4:28
Speaker 3: have a position, it's here, they have velocity. It's moving
4:30
Speaker 3: that fast, right, And.
4:32
Speaker 2: If the wire gets hot, it's because those little balls
4:34
Speaker 2: are I don't know, crashing into things, greating friction.
4:38
Speaker 3: That is the Grood model from like nineteen hundred. It
4:41
Speaker 3: treats electrons like pinballs, and for i'd say ninety nine
4:45
Speaker 3: percent of electrical engineering, that model is fantastic work helps
4:48
Speaker 3: us design circuits, fuse boxes, toasters. But here is the
4:53
Speaker 3: secret that physicists don't really tell you until you're in
4:56
Speaker 3: grad school. It's not really true.
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Speaker 2: I feel, but t trade My entire high school education
5:02
Speaker 2: is a lie.
5:02
Speaker 3: Don't be It's a very very useful fiction. In reality,
5:05
Speaker 3: Inside that wire you have billions of electrons interacting with
5:09
Speaker 3: billions of atomic nuclei, and they are all pushing and
5:11
Speaker 3: pulling on each other simultaneously. It's a it's a quantum mess.
5:14
Speaker 3: It's a soup.
5:15
Speaker 2: So how do we do any math if it's just
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Speaker 2: a soup? Yeah, you can't calculate the trajectory of a soup.
5:19
Speaker 3: You can't. So we use a trick, a very very
5:21
Speaker 3: clever mathematical trick called quasi particles.
5:24
Speaker 2: Quasi particles, which implies fake particles.
5:27
Speaker 3: Almost particles, or as if particles. Think of it this way.
5:31
Speaker 3: Imagine you were at a really crowded concert. Okay, packed
5:34
Speaker 3: shoulder to shoulder. If you try to track one specific
5:37
Speaker 3: person moving from the back of the room to the stage,
5:40
Speaker 3: it's really hard. They are getting shoved, turned around, stuck impossibly.
5:44
Speaker 2: Yeah.
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Speaker 3: But now imagine a small circle of empty space opens
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Speaker 3: up in the crowd, a gap, and that gap moves
5:51
Speaker 3: towards the bar.
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Speaker 2: Okay, I can track the gapees, I can see it
5:54
Speaker 2: moving exactly.
5:55
Speaker 3: But the gap isn't a person. It's the absence of people,
5:58
Speaker 3: but it moves like a person. It has a speed,
6:01
Speaker 3: it has a location. So in physics we treat that
6:04
Speaker 3: collective behavior, that gap, as if it were a particle.
6:07
Speaker 3: We give it a mass, we give it a charge,
6:08
Speaker 3: and we do the math on the gap, not on
6:10
Speaker 3: the whole crowd.
6:11
Speaker 2: That is genius. So we just we pretend the collective
6:13
Speaker 2: mess is actually just a bunch of simple, well behaved objects,
6:16
Speaker 2: and the math works out precisely.
6:18
Speaker 3: That is the entire foundation of modern solid state physics.
6:23
Speaker 3: We turn these incredibly complex interactions into simple quasi particles.
6:28
Speaker 3: And this has been the role. I mean, even the
6:30
Speaker 3: most advanced Nobel Prize winning theories of the last decade
6:34
Speaker 3: have relied on this fundamental assumption.
6:36
Speaker 2: It's the assumption that if you look closely.
6:38
Speaker 3: Enough, you can find a quasi particle to hang your
6:41
Speaker 3: hat on.
6:41
Speaker 2: So the idea is it might be complicated, but eventually,
6:45
Speaker 2: when you boil it down, it acts like a particle.
6:48
Speaker 3: Yes, that was the bedrock until now.
6:52
Speaker 2: Enter the disruptor. Hmmm, the Vienna team. They were looking
6:56
Speaker 2: at a specific material with a name that it sounds
7:01
Speaker 2: like a distinct lack of creativity. It does three four
7:04
Speaker 2: SN six.
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Speaker 3: It's purely descriptive serium, ruthenium, and ten. It tells you
7:07
Speaker 3: the ingredients.
7:07
Speaker 2: I feel like they could have named it V and
7:09
Speaker 2: I or something cooler, but okay, or four SN six.
7:12
Speaker 2: What makes this alphabet soup so special?
7:14
Speaker 3: So it was called a heavy fermion system, which is
7:17
Speaker 3: just physicists speak for the electrons here interact really, really strongly.
7:21
Speaker 3: But the key isn't just the material itself, it's what
7:24
Speaker 3: they did to it. They cooled it down to temperatures
7:27
Speaker 3: that are just they're mind boggling.
7:30
Speaker 2: How cold are we talking?
7:31
Speaker 3: We are talking Millie Kilvin's a tiny tiny fraction of
7:36
Speaker 3: a degree above absolute zero.
7:38
Speaker 2: Okay, so that's colder than deep space, colder than the
7:41
Speaker 2: dark side of the.
7:42
Speaker 3: Moon, oh much much colder. And at these temperatures, this
7:46
Speaker 3: material enters a state called quantum criticality.
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Speaker 2: That sounds like the alarm that goes off on a
7:50
Speaker 2: spaceship right before it explodes, warning quantum criticality reached.
7:55
Speaker 3: It's not quite that dramatic, but it's almost. It's more
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Speaker 3: like a state of supreme indecision.
8:01
Speaker 2: Indecision. How can the material be indecisive?
8:04
Speaker 3: Okay, So imagine a coin spinning on a table. When
8:07
Speaker 3: it's spinning, is it heads or tails?
8:09
Speaker 2: It's neither, it's both at the same time, kind of right.
8:12
Speaker 3: Usually in nature, the coin eventually falls, water freezes into ice,
8:17
Speaker 3: steam condenses into water. A magnet aligns north or south.
8:21
Speaker 3: Nature likes to make a choice. We call that a
8:22
Speaker 3: phase transition.
8:23
Speaker 2: But in this material, it doesn't choose.
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Speaker 3: In this quantum critical state, the material refuses to choose.
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Speaker 3: It is poised on this razor's edge between two different
8:34
Speaker 3: possible states let's just say magnetic and non magnetic for simplicity,
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Speaker 3: and it fluctuates wildly between them.
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Speaker 2: So it's flickering.
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Speaker 3: It's flickering exactly. Diana Kirschbaum, the lead author on the paper,
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Speaker 3: She describes it as a state where the material cannot
8:48
Speaker 3: decide which one it wants to adopt. And because it's
8:51
Speaker 3: flickering so fast and so violently, the interactions between the electrons,
8:56
Speaker 3: they effectively become infinite definite interactions. That sounds bad, It's
8:59
Speaker 3: just it means there so strongly dominate everything. And when
9:02
Speaker 3: those interactions become that strong are trick the quasi particle,
9:06
Speaker 3: it breaks.
9:07
Speaker 2: The gap in the crowd disappears.
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Speaker 3: The crowd becomes a mash pit, a liquid, a blur.
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Speaker 3: You can no longer identify a distinct thing moving through
9:15
Speaker 3: the system. You can't say, here is a particle with
9:18
Speaker 3: mass X and velocity y. The mass becomes undefined, the
9:21
Speaker 3: velocity becomes undefined. The particle picture dissolves completely into a
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Speaker 3: quantum soup.
9:25
Speaker 2: Okay, I'm with you. We have a soup. No billiard balls,
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Speaker 2: no quasi particles, just raw, throbbing quantum chaos.
9:33
Speaker 3: And this is where the conflict arises, because logically, if
9:36
Speaker 3: you don't have.
9:37
Speaker 2: Particles, you can't have structure.
9:39
Speaker 3: You can have geometry.
9:40
Speaker 2: This brings us to the other big concept we need
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Speaker 2: to tackle, topology.
9:43
Speaker 3: The twenty sixteen Nobel Prize a huge deal in physics.
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Speaker 2: Right, this word gets thrown around a lot topological quantum matter.
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Speaker 2: It sounds very, very fancy, but at its core it's
9:55
Speaker 2: about shapes.
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Speaker 3: Right, It's about a very specific kind of shape analysis.
10:00
Speaker 3: Topology is often called rubber sheet geometry. In normal Euclidean geometry,
10:06
Speaker 3: a square is different from a circle because a square
10:09
Speaker 3: has corners and straight edges. Sure, in topology, we don't
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Speaker 3: care about corners or straightness. We only care about one thing. Holes.
10:18
Speaker 2: This is where the donuts come in.
10:19
Speaker 3: It's always the donuts. So imagine you have a ball
10:21
Speaker 3: of plater. You can squash it, you can stretch it,
10:23
Speaker 3: you can twist it, you can flatten it into a pancake. Topologically,
10:27
Speaker 3: the ball and the pancake are exactly the same because.
10:29
Speaker 2: I didn't tear it or poke a new hole in it, exactly.
10:32
Speaker 3: But if I want to turn that ball into.
10:34
Speaker 2: A donut, you have to poke a hole through the middle.
10:36
Speaker 3: You have to perform a violent act. You have to
10:38
Speaker 3: tear the material. That tearing is a change in topology.
10:43
Speaker 3: So we classify objects by their number of holes. A
10:46
Speaker 3: ball has zero holes, a doughnut has one hole, a
10:49
Speaker 3: pretzel has three holes.
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Speaker 2: What about a coffee mug. I've heard this one.
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Speaker 3: A coffee mug has one hole, the one in the handle.
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Speaker 3: So topologically a coffee mug is identical to a donut.
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Speaker 3: You can imagine squishing the cup part of the mug
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Speaker 3: into the ring of the handle without ever tearing it.
11:04
Speaker 2: Okay, I love that mental image. Okay, but electrons aren't donuts.
11:08
Speaker 2: They don't have handles. How does this apply to the
11:11
Speaker 2: quantum soup?
11:12
Speaker 3: It applies to the mathematics that describe the electrons, and
11:14
Speaker 3: we map out all their possible quantum states, their energy levels,
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Speaker 3: their momentum, their spin. That map can have a shape,
11:21
Speaker 3: and sometimes that abstract mathematical map has a hole or
11:25
Speaker 3: a knot in it. A mathematical donut, mathematical donut exactly.
11:29
Speaker 3: And here's the crucial part. Just like a real donut
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Speaker 3: keeps its hole, even if you dent it or take.
11:34
Speaker 2: A bite out of it, it's still the donut.
11:36
Speaker 3: It's still a donut. A topological material keeps its special
11:39
Speaker 3: electrical properties even if the wire is dirty or bent
11:42
Speaker 3: or has some impurities. It is incredibly robust.
11:45
Speaker 2: And this is why everyone is so excited about it.
11:47
Speaker 2: For technology, it's bulletproof physics.
11:50
Speaker 3: It is. But here's the catch. The entire definition of
11:54
Speaker 3: topological matter, the definition that won that Nobel prize, it
11:58
Speaker 3: relies on describing the shape of the particle.
12:01
Speaker 2: The shape of the dancers, not the dance.
12:02
Speaker 3: Yes, you analyze the wave function of the quasi particles
12:07
Speaker 3: to see if their mathematical space has a hole in it.
12:09
Speaker 2: Okay, so syllogism time. Let's see if I have this
12:13
Speaker 2: right premise, ie, you need particles to define topology. That
12:17
Speaker 2: was the assumption. Yere premi is two. This zero four
12:19
Speaker 2: EKA and six stuff in its quantum critical state has
12:22
Speaker 2: no particles.
12:23
Speaker 3: Correct, The picture dissolves conclusion.
12:25
Speaker 2: Therefore zero four s, A and six cannot have any
12:28
Speaker 2: topological properties.
12:29
Speaker 3: That was the prevailing wisdom. That was the logic. It's
12:32
Speaker 3: perfectly sound. If the particle picture breaks down, the topological
12:35
Speaker 3: classification should break down with it.
12:37
Speaker 2: And this wasn't just some abstract theoretical annoyance. This actually
12:41
Speaker 2: affected the scientists in the lab right. They hesitated it did.
12:45
Speaker 3: Science is done by humans, and humans have doubts and biases.
12:49
Speaker 3: There were some theoretical models, just math done on paper,
12:52
Speaker 3: hinting that maybe, just maybe this material could host topological states.
12:58
Speaker 3: But the experimental team at ten they were reluctant.
13:03
Speaker 2: Why why not just look?
13:05
Speaker 3: Because it felt like a complete wild goose chase. Professor
13:08
Speaker 3: Silka Bueler Passion, who led the team, she spoke about this,
13:12
Speaker 3: Why would you spend all this time and money and
13:14
Speaker 3: effort looking for a delicate ordered geometric structure and a
13:18
Speaker 3: material that is essentially a chaotic, fluctuating blur, like looking.
13:22
Speaker 2: For a perfect snowflake in a blender.
13:24
Speaker 3: That's a perfect analogy. It seemed contradictory, illogical, but they
13:28
Speaker 3: did it anyway. Curiosity prevailed. Diana Kirschbaum, the PhD student
13:32
Speaker 3: and first author on the paper, she pushed to investigate it.
13:35
Speaker 3: And it's just that beautiful spark of science. Right. The
13:37
Speaker 3: theory says X. My intuition says, why, let's just ask
13:40
Speaker 3: the universe what it actually thinks.
13:41
Speaker 2: So they fired up the world's coldest fridge. They cooled
13:45
Speaker 2: this stuff down to near absolute zero, and they went
13:48
Speaker 2: looking for the donut. How do you even look for
13:51
Speaker 2: a mathematical doughnut in a rock?
13:53
Speaker 3: You look for something called the Hall effect.
13:55
Speaker 2: Okay, we need to break this down. The Hall effect
13:57
Speaker 2: sounds familiar. Like from college.
13:59
Speaker 3: Physics as a classic. It was discovered way back in
14:02
Speaker 3: eighteen seventy nine. Here's the basic setup. You have a flat,
14:06
Speaker 3: thin strip of metal. You run a current through it,
14:09
Speaker 3: let's say from north to south.
14:11
Speaker 2: Okay, So electrons are flowing down the.
14:13
Speaker 3: Highway, cruising along. Now you bring a strong magnet close
14:17
Speaker 3: to the strip with its field pointing, say straight up.
14:21
Speaker 3: That magnetic field exerts a force, the Lorentz force that
14:24
Speaker 3: pushes the moving electrons sideways.
14:26
Speaker 2: Like a strong crosswind hitting the cars on the highway exactly.
14:29
Speaker 3: So the electrons instead of going straight, they start to
14:32
Speaker 3: curve and pile up on let's say the west side
14:35
Speaker 3: of the strip. That pile up of negative charge creates
14:38
Speaker 3: a voltage difference between the west side and the east side.
14:40
Speaker 3: We call that the Hall voltage.
14:42
Speaker 2: Okay, so the simple rule is no magnet equals no
14:46
Speaker 2: sideways voltage. You apply a magnet, you get a sideways voltage.
14:49
Speaker 3: Correct. That's the rule. But in topological materials there's a twist. Literally,
14:55
Speaker 3: if the mathematical structure of the material has that doughnut shape,
14:58
Speaker 3: that topological twist, it acts like an internal magnetic field.
15:02
Speaker 2: The material itself pushes the electrons to the side.
15:05
Speaker 3: The geometry of the quantum states pushes the electrons. This
15:08
Speaker 3: is called the anomalous Hall effect. You see the electrons
15:11
Speaker 3: swerving to the side without applying any external magnet at all.
15:15
Speaker 2: So it's like the banked turn on a racetrack. The
15:18
Speaker 2: cars turn not because the driver is steering, but because
15:22
Speaker 2: the road itself is curved.
15:23
Speaker 3: That is a perfect analogy. The very curvature of the
15:26
Speaker 3: quantum wave function acts precisely like a banked turn for electrons.
15:30
Speaker 2: So the team in Vienna hooks up their electrodes to
15:33
Speaker 2: this particleless soup, expecting to see what nothing.
15:37
Speaker 3: If the logic held that no particles means no topology,
15:41
Speaker 3: they should have seen absolutely zero anomalous Hall effect. The
15:45
Speaker 3: cars shouldn't swerve because well, there are no cars and
15:47
Speaker 3: there's no road.
15:48
Speaker 2: And what did they see.
15:49
Speaker 3: They saw a massive signal, a huge anomalous Hall effect.
15:52
Speaker 3: The electrons were swerving hard without a magnet, Without any
15:56
Speaker 3: external magnet, they found the signature of the doughnut.
15:58
Speaker 2: But but how you.
16:01
Speaker 3: Just told me. The particles dissolved, the cars aren't there.
16:03
Speaker 2: That's the breakthrough, that's the discovery. They found that the topology.
16:07
Speaker 2: The geometry was surviving the death of the particles, the smile.
16:11
Speaker 3: Of the chessure cat hanging in the air after the
16:14
Speaker 3: cat has faded.
16:15
Speaker 2: Away, precisely and it gets even weirder, even more profound.
16:19
Speaker 2: They mapped out when this effect happened, and they found
16:22
Speaker 2: that this swerving, this topological signal was at its strongest
16:28
Speaker 2: exactly when the quantum critical fluctuations were the most violent.
16:31
Speaker 3: Wait a second, so the chaos wasn't destroying the geometry.
16:34
Speaker 2: The chaos was creating the geometry.
16:36
Speaker 3: That is completely counterintuitor.
16:38
Speaker 2: It turns everything on its head. They did a control experiment.
16:41
Speaker 2: If they applied pressure or a strong magnetic field to
16:44
Speaker 2: force the material to choose a state, to stop fluctuating
16:48
Speaker 2: and become a normal, well behaved material, again the topological
16:52
Speaker 2: effect vanished.
16:53
Speaker 3: So if you fix the material's identity crisis, the magic
16:57
Speaker 3: goes away, exactly the doughnut shape. The topology only exists
17:02
Speaker 3: because of the quantum criticality. The intense collective interactions between
17:06
Speaker 3: the electrons that infinite mosh pit are what actually generate
17:10
Speaker 3: the topological state.
17:12
Speaker 2: So this is a fundamentally new thing. They had to
17:14
Speaker 2: coin a new term for it.
17:16
Speaker 3: They did. They're calling it an emergent topological semi metal emergent.
17:20
Speaker 2: Yeah, that's a heavy word in physics.
17:22
Speaker 3: It is It implies that the property arises from the
17:25
Speaker 3: collective behavior. It's not a property that's built into the
17:28
Speaker 3: individual pieces. It emerges from the complex way they dance together.
17:33
Speaker 2: It's like consciousness, right. You can't find consciousness in a
17:35
Speaker 2: single neuron. It's not a property of the neuron. Yeah,
17:38
Speaker 2: but you put billions of them together and let them interact,
17:41
Speaker 2: and suddenly you have a mind.
17:43
Speaker 3: That's a fantastic parallel. You can't find the topology in
17:45
Speaker 3: a single electron, but you put them in this critical,
17:49
Speaker 3: fluctuating state, and this robust topological order emerges from the chaos.
17:54
Speaker 2: They didn't just observe this, they explained it too. I read.
17:57
Speaker 2: They brought in some heavy theoretical backup.
17:59
Speaker 3: Yes, and from Rice University in Texas, led by professor
18:02
Speaker 3: Kimyosi and Lei Chen. They did the heavy lifting on
18:05
Speaker 3: the mathematical modeling. They built a new theoretical framework that
18:09
Speaker 3: combines quantum criticality, the fluctuations with the concepts of topology.
18:14
Speaker 2: They wrote the Peace Treaty between Chaos and order.
18:16
Speaker 3: In a way. Yes, and they proved mathematically that you
18:20
Speaker 3: don't need the particle for the geometry to exist. Professor
18:24
Speaker 3: Bueler Passion summed it up perfectly in their press release.
18:26
Speaker 3: She said, a particle picture is not required.
18:29
Speaker 2: That is such a dry scientific way to say something
18:32
Speaker 2: that basically breaks reality. A particle picture is not required.
18:36
Speaker 2: It's like saying, oh, by the way, gravity is optional
18:39
Speaker 2: on Tuesdays.
18:40
Speaker 3: It feels that big because it generalizes the entire concept
18:43
Speaker 3: of topology. It moves it from being a property of
18:47
Speaker 3: matter of particles to being a property of fields or
18:50
Speaker 3: interactions themselves. The geometry is more fundamental than the stuff.
18:54
Speaker 2: So we've established that the universe is fundamentally weirder than
18:58
Speaker 2: we thought. But let's bring this back to the why
19:00
Speaker 2: should I care? Factor? Because you mentioned earlier this is
19:02
Speaker 2: a blueprint for new technology.
19:04
Speaker 3: It is a huge one. Now that we know this
19:08
Speaker 3: state of matter exists, we can go out and hunt for.
19:10
Speaker 2: It, hunt for aware in other weird materials.
19:13
Speaker 3: In a whole class of materials we were previously ignoring.
19:17
Speaker 3: See before this, physicists who were looking for new topological materials,
19:22
Speaker 3: they generally avoided quantum critical systems. They thought, oh, that's
19:25
Speaker 3: too messy. The quasi particles aren't well defined, the math
19:28
Speaker 3: won't work there.
19:29
Speaker 2: They were looking for their keys under the street light
19:31
Speaker 2: because that's where the light was, not where they dropped
19:33
Speaker 2: them exactly.
19:34
Speaker 3: Now we know the keys are actually in the dark,
19:37
Speaker 3: messy alleyway, and we have a map to find them.
19:41
Speaker 3: This opens up a huge class of materials. We call
19:44
Speaker 3: them strongly correlated electron systems to be potential technological gold mines.
19:50
Speaker 2: Okay, so what are we building with this gold.
19:52
Speaker 3: Let's start with sensors. Remember the robustness, the undendable donut, right.
19:56
Speaker 3: Because the electrical signal in these materials is protected by
19:59
Speaker 3: g geometry, not by the purity of the material, it
20:02
Speaker 3: is incredibly resistant to noise, temperature fluctuations, small impurities in
20:08
Speaker 3: the crystal vibrations. They don't mess up the signal nearly
20:12
Speaker 3: as much.
20:13
Speaker 2: So if I'm building an ultrasensitive sensor for an MRI
20:15
Speaker 2: machine or a satellite telescope or a gravity wave detector, you.
20:19
Speaker 3: Get a signal that is fundamentally cleaner and more stable.
20:22
Speaker 3: You get a level of sensitivity that we currently can't
20:25
Speaker 3: achieve with conventional electronics.
20:28
Speaker 2: That's huge Okay, what about energy.
20:30
Speaker 3: That steering without magnets aspect the anomalous Hall effect right now,
20:36
Speaker 3: to manage power flows or steer currents and computer chips,
20:39
Speaker 3: we use a lot of components that rely on resistance,
20:42
Speaker 3: which creates waste heat.
20:44
Speaker 2: That's the heat that's killing my phone's battery life.
20:46
Speaker 3: It is. Now, imagine if the material steered the current
20:49
Speaker 3: for you simply because of its intrinsic geometric shape. It's
20:53
Speaker 3: a frictionless process. It's what we call dissipationless.
20:56
Speaker 2: Just flows like water down a perfectly shaped hill.
20:59
Speaker 3: Exactly. It could lead to a new generation of electronics
21:02
Speaker 3: that are drastically more energy efficient.
21:04
Speaker 2: And then there is the big one, the one everyone
21:06
Speaker 2: always talks about, quantum computing.
21:09
Speaker 3: Holy Grail.
21:10
Speaker 2: We've been hearing about quantum computers for twenty years. It's
21:14
Speaker 2: always they're coming next year. Why is it taking so long?
21:18
Speaker 3: The short answer is because quantum states are incredibly fragile.
21:23
Speaker 3: A quibit, a quantum bit is like a soap bubble.
21:26
Speaker 3: If a stray photon hits it, if it vibrates too much,
21:29
Speaker 3: if it gets just a little too warm, pop, the
21:32
Speaker 3: information is lost. This is a process called decoherence.
21:36
Speaker 2: So we spend all our energy and resources trying to
21:39
Speaker 2: build these elaborate refrigerators to keep the bubble from popping.
21:42
Speaker 3: Right, But there is a different approach, a theoretical one
21:45
Speaker 3: called topological quantum.
21:47
Speaker 2: Computing, using the donut.
21:49
Speaker 3: Using the donut. Instead of storing the information in the
21:52
Speaker 3: fragile state of a single particle, like the orientation of
21:55
Speaker 3: a soap bubble, you store it in the topology. You
21:58
Speaker 3: store it in the existence of the whole itself.
22:00
Speaker 2: You can't pop a hole.
22:01
Speaker 3: You can't pop a hole exactly. You can shake the material,
22:04
Speaker 3: you could heat it up a little, you can have
22:06
Speaker 3: a defect, but the whole remains. The information is topologically protected.
22:10
Speaker 2: So this discovery in Vienna, hmm, it's a huge step
22:14
Speaker 2: towards that.
22:15
Speaker 3: It proves that these robust topological states can exist even
22:19
Speaker 3: in messy, fluctuating, hot quantum environments. It suggests that this
22:24
Speaker 3: emergent topology might be the best place to look to
22:27
Speaker 3: build a stable quibot that doesn't need to be perfectly
22:30
Speaker 3: isolated from the world.
22:31
Speaker 2: It's like nature's own error correction is built right in.
22:33
Speaker 3: That is a great way to put it. It's error
22:35
Speaker 3: correction by geometry I want to take.
22:37
Speaker 2: A step back and just look at the philosophical side
22:40
Speaker 2: of this for a minute, because we started this whole
22:42
Speaker 2: conversation with the simple idea that stuff is made of particles,
22:46
Speaker 2: the lego blocks, the lego blocks, and we have ended
22:49
Speaker 2: up with stuff is made of geometry that emerges from chaos.
22:54
Speaker 2: That's a big leap.
22:56
Speaker 3: It's a transition from a material view of the universe
22:59
Speaker 3: to a structural or informational view.
23:02
Speaker 2: It really feels like we are peeling back a layer
23:04
Speaker 2: of the onion and finding out there is no onion
23:07
Speaker 2: at the center. There's just the shape of where the
23:08
Speaker 2: onion used to be.
23:10
Speaker 3: There is a theory in fundamental physics. It's speculative, but
23:13
Speaker 3: it's gaining traction that perhaps everything is geometry, that particles
23:18
Speaker 3: like electrons and quirks aren't really fundamental things at all,
23:21
Speaker 3: but are just persistent knots in the fabric of space
23:24
Speaker 3: time or twists in an underlying quantum field.
23:29
Speaker 2: So if you can somehow untie the knot, the electron
23:32
Speaker 2: would just vanish.
23:33
Speaker 3: It would vanish, leaving behind flat space time. And this discovery,
23:37
Speaker 3: the fact that you can have the topological property the
23:40
Speaker 3: geometry without the well defined particle is a strong piece
23:44
Speaker 3: of experimental evidence for that worldview. It suggests that the
23:47
Speaker 3: geometry is the more fundamental reality. The particle is just
23:51
Speaker 3: a temporary symptom of the geometry that is profound.
23:55
Speaker 2: It means that when I touch this table, I'm not
23:57
Speaker 2: actually touching matter. I'm touching a geometric rule says your
24:00
Speaker 2: hand cannot pass through this region of space.
24:03
Speaker 3: You are interacting with a topology that resists your hand. Ye.
24:06
Speaker 2: Yes, I'm going to be thinking about that for a week.
24:07
Speaker 3: That's Yeah, it's the kind of thought that keeps physicists
24:10
Speaker 3: up at night, But in a good way.
24:13
Speaker 2: It means there was still so much to discover. We
24:15
Speaker 2: really thought we had the rule book pretty.
24:17
Speaker 3: Much written, and nature just handed us a new appendix.
24:20
Speaker 2: Or maybe a whole new volume, probably a whole new volume.
24:23
Speaker 3: Yeah.
24:23
Speaker 2: Before we wrap up, I just want to give a
24:25
Speaker 2: shout out to the human element here again, because it
24:28
Speaker 2: would have been so easy for that team at t
24:30
Speaker 2: Uwaine to say the logic says, no, let's save the money,
24:34
Speaker 2: let's not run the experiment.
24:36
Speaker 3: It would have been the completely rational choice based on
24:39
Speaker 3: existing theory.
24:40
Speaker 2: Look, they didn't, Yeah, they chose curiosity over convention. They
24:44
Speaker 2: chose to look in the blender for the snowflake.
24:47
Speaker 3: And that is how all the best science happens. It
24:49
Speaker 3: happens when someone looks at a contradiction and says, that's funny,
24:52
Speaker 3: instead of that's impossible.
24:54
Speaker 2: That's funny. Isaac Asimov said that was the most important
24:57
Speaker 2: phrase in science.
24:58
Speaker 3: It was absolutely right.
25:00
Speaker 2: So for the listener who is currently feeling like their
25:03
Speaker 2: physical reality has been slightly dissolved around them, what is
25:07
Speaker 2: the one big thing they should take away from all this?
25:09
Speaker 3: I would say this, don't get too attached to your models.
25:12
Speaker 3: The particle picture is a model. It's a tool. It's
25:15
Speaker 3: a great tool for fixing a toaster or building a bridge,
25:19
Speaker 3: but it's not the ultimate truth. The universe is more fluid,
25:22
Speaker 3: it's more emergent, and it's surprisingly more geometric than our
25:26
Speaker 3: simple pictures allow.
25:27
Speaker 2: And sometimes you have to lose the cat to really
25:30
Speaker 2: find the smile.
25:31
Speaker 3: I couldn't have set it better myself.
25:32
Speaker 2: Thank you so much for guiding us through the quantum soup.
25:36
Speaker 2: My brain hurts, but in the best possible way.
25:38
Speaker 3: It was a pleasure, always fun to question reality.
25:41
Speaker 2: And to everyone listening, keep asking the simple questions. Ask
25:45
Speaker 2: what stuff is made of, Ask why the light comes on,
25:49
Speaker 2: And when the answer doesn't quite make sense, dig deeper.
25:52
Speaker 2: We'll see you next time.