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The Strange Quantum Particles Carrying a Fraction of an Electron · The Quark Side - Quantum Physics Podcast

• 0:01
  Speaker 1: Welcome to the Quarkside Quantum Physics Podcast, an exploration of
• 0:05
  Speaker 1: 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.
• 0:18
  Speaker 2: At the smallest scales.
• 0:27
  Speaker 3: I want you to imagine, just for a second, a
• 0:30
  Speaker 3: regular everyday coin. Like, let's say a penny.
• 0:33
  Speaker 2: Okay, a penny.
• 0:35
  Speaker 1: Right.
• 0:35
  Speaker 3: You've got it in your pocket. You can feel the
• 0:37
  Speaker 3: copper edges. You know its weight. And in our everyday world,
• 0:40
  Speaker 3: that penny is a fixed, indivisible unit.
• 0:43
  Speaker 2: Yeah, you definitely can't hand a cashier a quarter of
• 0:46
  Speaker 2: a penny. Exactly.
• 0:47
  Speaker 3: You can't just take a pair of tin snips, slice
• 0:50
  Speaker 3: it into four pieces, and try to spend the fractions.
• 0:53
  Speaker 3: I mean, the entire financial system simply does not allow it.
• 0:56
  Speaker 2: It's the bottom floor.
• 0:58
  Speaker 3: Right. The penny is the absolute bottom floor. And for
• 1:01
  Speaker 3: over a century, that is exactly how we have understood
• 1:04
  Speaker 3: the electric charge of an electron. It has always been,
• 1:07
  Speaker 3: you know, the fundamental, unbreakable unit of the universe.
• 1:11
  Speaker 2: It's the penny of particle physics, basically.
• 1:13
  Speaker 3: Yes. But today, we are looking at a breakthrough that
• 1:16
  Speaker 3: completely shatters that idea. Because scientists have managed to measure
• 1:20
  Speaker 3: particles that hold exactly one quarter of an electron's charge.
• 1:25
  Speaker 2: Which is just wild to think about.
• 1:26
  Speaker 3: It is. They have essentially broken the unbreakable unit of electricity.
• 1:31
  Speaker 3: And when you first hear that, I mean, it sounds
• 1:33
  Speaker 3: like magic or maybe just a really bad math error.
• 1:36
  Speaker 2: Yeah, the initial concept totally challenges your basic intuition. But
• 1:40
  Speaker 2: to make sense of it, we really have to establish
• 1:42
  Speaker 2: a crucial distinction right away.
• 1:44
  Speaker 3: Okay, what's that?
• 1:46
  Speaker 2: We aren't talking about isolating a single electron, putting it
• 1:49
  Speaker 2: under some microscopic laser, and physically slicing it into four pieces.
• 1:54
  Speaker 3: Oh, so the actual fundamental electron isn't being chopped up.
• 1:59
  Speaker 2: No, no. The fundamental electron itself remains whole, always.
• 2:03
  Speaker 3: Wait, so if we aren't slicing a single electron into quarters,
• 2:06
  Speaker 3: where is this fractional charge even coming from?
• 2:09
  Speaker 2: Well, it emerges from something called a collective state.
• 2:12
  Speaker 3: A collective state, okay.
• 2:13
  Speaker 2: Right. So when you subject electrons to incredibly extreme, highly
• 2:18
  Speaker 2: specific physical conditions, they stop acting like, you know, isolated
• 2:22
  Speaker 2: independent particles bouncing around.
• 2:24
  Speaker 3: They lose their individuality.
• 2:25
  Speaker 2: Exactly. They organize. They merge their behaviors and interactions to
• 2:29
  Speaker 2: create entirely new entities. And in physics, we call these quasi-particles.
• 2:34
  Speaker 3: Quasi-particles.
• 2:35
  Speaker 1: Yeah.
• 2:36
  Speaker 2: They're born from the collective, and they behave as if
• 2:38
  Speaker 2: they possess fractional charges.
• 2:40
  Speaker 3: I mean, I'm trying to visualize how a collection of
• 2:42
  Speaker 3: whole things creates a fraction. Because if you put a
• 2:46
  Speaker 3: bunch of whole pennies together, you just get, well, more pennies.
• 2:49
  Speaker 3: You don't get a quarter of a penny.
• 2:52
  Speaker 2: That's true. So think about a massive stadium crowd instead
• 2:56
  Speaker 2: of a pocket full of coins. Okay.
• 2:58
  Speaker 3: I'm at a football game.
• 2:59
  Speaker 1: Right.
• 3:00
  Speaker 2: Picture tens of thousands of people in the stands doing
• 3:03
  Speaker 2: the wave. If you just isolate one single person standing
• 3:07
  Speaker 2: up and sitting back down.
• 3:09
  Speaker 3: That person is not a wave.
• 3:11
  Speaker 2: Exactly. A single human being cannot possess the properties of
• 3:14
  Speaker 2: a wave.
• 3:15
  Speaker 3: They're just doing a jumping jack. Right.
• 3:18
  Speaker 2: But when that entire crowd perfectly coordinates their motion... A
• 3:22
  Speaker 2: completely new, measurable entity sweeps around the arena.
• 3:25
  Speaker 3: The wave itself becomes a real thing.
• 3:28
  Speaker 2: Yes, you can track its speed, measure its height, predict
• 3:31
  Speaker 2: its path. But it only exists because of the collective,
• 3:35
  Speaker 2: synchronized action of the individuals.
• 3:38
  Speaker 3: Ah, so the quasi-particle is the wave in the stadium.
• 3:42
  Speaker 2: The quasi-particle is the wave. And in the bizarre reality
• 3:45
  Speaker 2: of quantum mechanics, this specific wave possesses a property, a
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  Speaker 2: distinct one-quarter charge, that none of the individual people in
• 3:53
  Speaker 2: the stadium could possibly possess on their own. Wow.
• 3:57
  Speaker 3: So the collective motion generates a physical reality that the
• 4:01
  Speaker 3: individual parts can't.
• 4:02
  Speaker 2: Exactly. It's a completely emergent property.
• 4:05
  Speaker 3: Okay, that makes the what much clearer, but it raises
• 4:08
  Speaker 3: a massive how. Because electrons don't normally do this. I mean,
• 4:12
  Speaker 3: they actively repel each other, right?
• 4:14
  Speaker 1: Oh, yeah.
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  Speaker 2: Very strongly.
• 4:16
  Speaker 3: So what kind of extreme quantum sandbox do you have
• 4:19
  Speaker 3: to build to force them into this highly coordinated stadium wave?
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  Speaker 3: Because reality doesn't just rewrite its own rules without some
• 4:26
  Speaker 3: serious coercion.
• 4:27
  Speaker 2: The coercion is immense. I mean, the phenomenon we're dealing
• 4:30
  Speaker 2: with here is known as the fractional quantum Hall effect.
• 4:34
  Speaker 3: The fractional quantum Hall effect? Right.
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  Speaker 2: And to force electrons to exhibit this, researchers have to
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  Speaker 2: build a very specific, literally flawless playground. And the foundation
• 4:45
  Speaker 2: of this playground is a material called gallium arsenide.
• 4:49
  Speaker 3: Which, just to give you some context, gallium arsenide isn't
• 4:51
  Speaker 3: some mythical element we only find in secret government labs.
• 4:55
  Speaker 2: No, not at all.
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  Speaker 3: It's actually a material you might have in your house
• 4:59
  Speaker 3: right now. It's heavily used in, like, solar panels and
• 5:02
  Speaker 3: the chips inside wireless communication devices.
• 5:05
  Speaker 2: Yeah, it's very common in advanced electronics. But exactly how
• 5:09
  Speaker 2: the researchers structure it for this experiment is far from standard.
• 5:13
  Speaker 3: They don't just use a big block of the stuff, right?
• 5:15
  Speaker 1: No.
• 5:16
  Speaker 2: They confine the electrons within a layer of this gallium
• 5:19
  Speaker 2: arsenide that is almost unimaginably thin. We're talking specifically about
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  Speaker 2: 70 nanometers wide.
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  Speaker 3: 70 nanometers. To put that in perspective for you, a
• 5:30
  Speaker 3: single human hair is roughly, what, 80,000 to 100,000 nanometers wide?
• 5:35
  Speaker 2: Yeah, roughly. So they are trapping these electrons in a
• 5:39
  Speaker 2: functionally two-dimensional pancake. And the purity of this layer is vital.
• 5:44
  Speaker 3: It has to be perfectly smooth.
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  Speaker 2: It has to be grown crystal by crystal, layer by
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  Speaker 2: atomic layer. There can be absolutely no defects or impurities
• 5:53
  Speaker 2: for the electrons to crash into.
• 5:55
  Speaker 3: Okay, so we trap them in a flawless 2D pancake. But,
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  Speaker 3: and hold on, I have to challenge the logic here.
• 6:01
  Speaker 1: Go ahead.
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  Speaker 3: Electrons carry a negative charge. Negative charges violently repel each other.
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  Speaker 3: So if you lock millions of them in a 70
• 6:08
  Speaker 3: nanometer flat plane and remove all their 3D space, wouldn't
• 6:13
  Speaker 3: they just repel each other even harder?
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  Speaker 2: You'd think so, yes.
• 6:16
  Speaker 3: It seems like it should just result in complete chaos,
• 6:19
  Speaker 3: like a microscopic mosh pit, not a beautifully synchronized stadium wave.
• 6:23
  Speaker 2: That is the exact paradox they use to their advantage.
• 6:26
  Speaker 2: You're completely right that squeezing them together normally creates chaotic repulsion.
• 6:31
  Speaker 3: So how do they tame the chaos?
• 6:33
  Speaker 2: They introduce the next two extremes. First, they cool this
• 6:37
  Speaker 2: material down to temperatures just a few fractions of a
• 6:41
  Speaker 2: degree above absolute zero. Wow.
• 6:43
  Speaker 3: So an environment so unimaginably cold that almost all ambient
• 6:47
  Speaker 3: thermal energy is just obliterated.
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  Speaker 2: Exactly. The cold removes their ability to jitter around. It
• 6:54
  Speaker 2: basically drains the energy they would normally use to randomly
• 6:57
  Speaker 2: crash into each other.
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  Speaker 3: It freezes out the thermal noise.
• 7:00
  Speaker 2: Right. It freezes them out. But then comes the final,
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  Speaker 2: decisive blow. They subject this freezing, two-dimensional layer to a massive,
• 7:10
  Speaker 2: overwhelmingly powerful magnetic field.
• 7:13
  Speaker 3: Okay, so they're frozen and now magnetized.
• 7:16
  Speaker 1: Yeah.
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  Speaker 2: In a normal environment, moving electrons travel in relatively straight
• 7:21
  Speaker 2: lines until they hit something. But under a strong magnetic field,
• 7:25
  Speaker 2: the rules change. The magnetic force pushes moving charges sideways.
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  Speaker 3: So they can't go straight anymore.
• 7:32
  Speaker 2: Exactly. It forces the electrons to travel in tight, quantized
• 7:36
  Speaker 2: circular orbits.
• 7:38
  Speaker 3: Okay, let me get this straight. They are trapped in
• 7:40
  Speaker 3: a flat plane, completely frozen, and now magnetically forced to
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  Speaker 3: run in tiny little circles.
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  Speaker 2: With nowhere to run, no thermal energy to fight with,
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  Speaker 2: and the magnetic field dictating their path, the normal chaotic
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  Speaker 2: repulsive behavior completely breaks down.
• 7:56
  Speaker 3: They just give up?
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  Speaker 2: More like they adapt. They are forced into a state
• 8:00
  Speaker 2: of deep quantum entanglement. To avoid hitting each other while
• 8:04
  Speaker 2: running in these mandatory circles, they have to perfectly synchronize
• 8:08
  Speaker 2: their movements. Oh, wow.
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  Speaker 3: So the repulsion actually becomes the glue that coordinates the dance.
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  Speaker 2: Exactly. They can't crash. So they lock into this unavoidable
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  Speaker 2: choreographed traffic jam. And that synchronized traffic jam is the
• 8:22
  Speaker 2: stadium wave.
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  Speaker 3: That's the quasi-particle.
• 8:25
  Speaker 2: That's the quasi-particle. The collective motion of this specific dance
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  Speaker 2: generates these exotic quantum states that scientists have spent decades
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  Speaker 2: hunting for.
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  Speaker 3: And how do they categorize these different states?
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  Speaker 2: They measure them using something called a filling factor, which
• 8:40
  Speaker 2: is usually represented by the Greek letter nu. Nu, okay.
• 8:45
  Speaker 2: The filling factor is basically just the ratio of the
• 8:47
  Speaker 2: number of electrons to the number of magnetic flux quanta.
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  Speaker 2: You can think of them as invisible magnetic threads piercing
• 8:54
  Speaker 2: through the material.
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  Speaker 3: So we are looking for a very specific ratio then.
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  Speaker 1: Right.
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  Speaker 2: Most fractional quantum Hall states have odd denominators, like one-third
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  Speaker 2: or one-fifth. Those are relatively well understood.
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  Speaker 3: But this one is different.
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  Speaker 2: Very different. The breakthrough we're exploring focuses on a highly elusive,
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  Speaker 2: incredibly rare category called even denominator states.
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  Speaker 3: Even denominator. So not one-third, but.
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  Speaker 2: The exact phenomenon isolated here is the nu equals one-half state.
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  Speaker 2: So for every two magnetic threads piercing the material, there
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  Speaker 2: is exactly one electron.
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  Speaker 3: Okay, but if we have successfully forced this incredibly rare
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  Speaker 3: one-half state into existence, how do we actually prove what
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  Speaker 3: it's doing?
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  Speaker 2: That's the real trick.
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  Speaker 3: Right, because it's one thing to theoretically map out this
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  Speaker 3: zero-degree magnetic dance and say, oh, it predicts a quarter-charge wave,
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  Speaker 3: but physically measuring it. You can't just take tweezers, pull
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  Speaker 3: a quasi-particle out of the deep freeze, and drop it
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  Speaker 3: on a bathroom scale.
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  Speaker 2: No, you definitely can't. And honestly, the measurement problem is
• 9:58
  Speaker 2: arguably the most brilliant aspect of this entire endeavor. The
• 10:02
  Speaker 2: teams at the EPFL in Switzerland, the Weizmann Institute of Science,
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  Speaker 2: and Princeton University had to figure out how to listen
• 10:09
  Speaker 2: to the quantum realm without disrupting the fragile state they'd
• 10:12
  Speaker 2: just created.
• 10:13
  Speaker 3: Wait, how do you listen to an electron wave trapped
• 10:17
  Speaker 3: in a freezing pancake?
• 10:18
  Speaker 2: They engineered a microscopic trap within that 70 nanometer gallium
• 10:23
  Speaker 2: arsenide layer using a very distinctive etching method. And by
• 10:27
  Speaker 2: carefully depositing metallic gates on top of the material, they
• 10:30
  Speaker 2: created what physicists call a quantum point contact.
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  Speaker 3: A quantum point contact. OK, let's make that tangible for everyone.
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  Speaker 2: Think of it as a toll booth on a highway
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  Speaker 2: or a severe bottleneck right in the middle of our
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  Speaker 2: 2D pancake. They apply a voltage to those metal gates,
• 10:47
  Speaker 2: which acts like an invisible electric fence.
• 10:51
  Speaker 3: Oh, so it pinches the path the electrons can take
• 10:53
  Speaker 3: until it's almost entirely closed?
• 10:55
  Speaker 2: Exactly. You are forcing these complex, coordinated stadium waves to
• 11:00
  Speaker 2: squeeze through an impossibly narrow gap.
• 11:03
  Speaker 3: And what happens when they squeeze through?
• 11:05
  Speaker 2: Because the bottleneck is so agonizingly tight, the flow of
• 11:08
  Speaker 2: quasiparticles is partially scattered. They can't maintain a smooth, continuous
• 11:13
  Speaker 2: flow anymore.
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  Speaker 3: They get backed up.
• 11:15
  Speaker 2: Right. They have to push through the gap at a random, erratic,
• 11:19
  Speaker 2: stop-and-start manner. And as these individual charge carriers pass through,
• 11:24
  Speaker 2: they generate tiny fluctuations in the electrical current.
• 11:27
  Speaker 3: So it creates a specific type of electrical turbulence.
• 11:30
  Speaker 2: Yes. And in physics, we call this turbulence shot noise.
• 11:35
  Speaker 2: By meticulously measuring the magnitude of this electrical noise, scientists
• 11:40
  Speaker 2: can calculate the actual physical size of the charge moving
• 11:43
  Speaker 2: through the bottleneck.
• 11:45
  Speaker 3: You know, the concept of shot noise can be a
• 11:46
  Speaker 3: little abstract, but it actually maps perfectly to rain hitting
• 11:50
  Speaker 3: a roof.
• 11:51
  Speaker 2: Oh yeah, that's a great way to think about it.
• 11:52
  Speaker 3: Right. So imagine you're standing inside a cabin, you're blindfolded,
• 11:57
  Speaker 3: and you are trying to figure out the exact size
• 12:00
  Speaker 3: of the water droplets falling outside. If someone turns on
• 12:03
  Speaker 3: a high-pressure garden hose and aims it right at the roof,
• 12:06
  Speaker 3: all you hear is a steady, continuous roar of water. Right.
• 12:08
  Speaker 2: The flow is way too high to distinguish any individual drop.
• 12:12
  Speaker 2: The continuous current just Hides the individual components. Exactly.
• 12:17
  Speaker 3: But if it starts to rain naturally, the flow is
• 12:19
  Speaker 3: broken up. The individual drops hit the tin roof in
• 12:22
  Speaker 3: a distinct, random stop and start pattering sound. Yep. A massive,
• 12:27
  Speaker 3: heavy thunderstorm drop makes a very loud, distinct thud, while
• 12:32
  Speaker 3: a tiny, misty drizzle drop makes a quiet, barely perceptible tap.
• 12:36
  Speaker 2: And by carefully listening to the volume and rhythm of
• 12:39
  Speaker 2: that patter, the electrical noise... you can mathematically deduce the
• 12:43
  Speaker 2: volume of the raindrop.
• 12:45
  Speaker 3: So the researchers are basically listening to the electrical patter
• 12:49
  Speaker 3: of these charges squeezing through the tollbooth.
• 12:51
  Speaker 2: Exactly. They are listening to the noise to figure out
• 12:54
  Speaker 2: the size of the quantum raindrop.
• 12:56
  Speaker 3: That is brilliant. But to make sure they weren't just
• 12:59
  Speaker 3: hearing things, they put this experimental design through a massive,
• 13:03
  Speaker 3: rigorous gauntlet, didn't they?
• 13:04
  Speaker 2: They had to. A single measurement from a single lab
• 13:07
  Speaker 2: in quantum physics is often viewed with deep skepticism.
• 13:11
  Speaker 3: Yeah, an anomaly in the equipment or a slight miscalibration
• 13:14
  Speaker 3: could easily produce a false positive.
• 13:16
  Speaker 2: Exactly. The scientific method demands reproducibility, so they built two
• 13:20
  Speaker 2: nearly identical devices and ran the experiments in two completely
• 13:24
  Speaker 2: independent laboratories, one at EPFL in Switzerland and one at
• 13:28
  Speaker 2: the Weizmann Institute in Israel.
• 13:30
  Speaker 3: They essentially set up a double-blind test for quantum mechanics.
• 13:33
  Speaker 2: They really did. And before they even attempted to listen
• 13:36
  Speaker 2: for the mysterious quarter charge, they had to prove their
• 13:39
  Speaker 2: tin roof actually worked.
• 13:41
  Speaker 3: How do you calibrate something that sensitive?
• 13:43
  Speaker 2: They calibrated their sensors using known states. They set the
• 13:47
  Speaker 2: conditions to produce a state where they already knew the
• 13:49
  Speaker 2: charge was a full normal electron.
• 13:51
  Speaker 3: Okay, start with a baseline.
• 13:53
  Speaker 1: Right.
• 13:54
  Speaker 2: Then they tested another state known to produce a charge
• 13:57
  Speaker 2: of exactly two-thirds of an electron.
• 13:59
  Speaker 3: And did the devices pass?
• 14:00
  Speaker 2: Perfectly. Both independent devices perfectly measured the known raindrop sizes.
• 14:06
  Speaker 2: The baseline was completely established, proving the sensitivity of their
• 14:09
  Speaker 2: quantum point contacts.
• 14:11
  Speaker 3: So only then did they shift the magnetic fields and
• 14:13
  Speaker 3: temperatures to summon that mysterious nu equals one half state?
• 14:17
  Speaker 2: Exactly. And when they directed that specific collective wave through
• 14:21
  Speaker 2: the toll booth, both independent labs arrived at a result
• 14:24
  Speaker 2: that is just beautiful in its precision.
• 14:27
  Speaker 3: What were the exact numbers?
• 14:29
  Speaker 2: The EPFL device measured a charge of 0.250 plus or
• 14:31
  Speaker 2: minus 0.013.
• 14:31
  Speaker 3: Wow.
• 14:31
  Speaker 2: And the Weizmann device measured 0.249 plus or minus 0.018.
• 14:41
  Speaker 3: That is incredible. They captured the fraction perfectly, exactly one
• 14:45
  Speaker 3: quarter of an electron's charge, E over 4.
• 14:48
  Speaker 2: The penny has officially been split into quarters.
• 14:51
  Speaker 3: It really has. But, and having reached this milestone, I
• 14:53
  Speaker 3: kind of have to play the ultimate skeptic for a minute.
• 14:56
  Speaker 2: Go for it.
• 14:56
  Speaker 3: Because while a 0.250 charge measurement is an undeniable triumph
• 15:00
  Speaker 3: of experimental physics, you might be wondering why this matters outside.
• 15:03
  Speaker 2: Of a laboratory. That's the million-dollar question. Right.
• 15:06
  Speaker 3: Like, why should anyone care about a quarter of a
• 15:08
  Speaker 3: charge surviving for a fraction of a second in a
• 15:09
  Speaker 3: freezing lab at a few kelvins?
• 15:11
  Speaker 2: It is the most important question to ask of any
• 15:13
  Speaker 2: fundamental research. But this is not just a trophy for
• 15:17
  Speaker 2: particle physicists. This discovery points directly toward the holy grail
• 15:21
  Speaker 2: of modern technology.
• 15:22
  Speaker 3: Which is?
• 15:23
  Speaker 2: Fault-tolerant topological quantum computing.
• 15:26
  Speaker 3: Okay, we definitely need to decode fault-tolerant topological quantum computing,
• 15:31
  Speaker 3: because the current state of standard quantum computers is, frankly,
• 15:35
  Speaker 3: notoriously and painfully fragile.
• 15:37
  Speaker 2: It really is. I mean, standard quantum computers use quantum bits,
• 15:41
  Speaker 2: or qubits, to perform calculations that would take a classical
• 15:44
  Speaker 2: supercomputer millions of years to solve.
• 15:46
  Speaker 3: Which sounds great, in theory.
• 15:48
  Speaker 1: It does.
• 15:49
  Speaker 2: But those standard qubits are incredibly sensitive. The slightest interference
• 15:52
  Speaker 2: from the outside world... can cause the qubit to collapse
• 15:55
  Speaker 2: and totally lose its state.
• 15:57
  Speaker 3: A tiny fluctuation in the room temperature, a stray electromagnetic
• 16:01
  Speaker 3: wave from a cell phone, or literally just background cosmic
• 16:04
  Speaker 3: radiation can ruin the calculation entirely.
• 16:07
  Speaker 2: Trying to run a complex algorithm on a standard quantum
• 16:10
  Speaker 2: computer is like trying to build a five-story house out
• 16:13
  Speaker 2: of balanced playing cards while sitting in the middle of
• 16:15
  Speaker 2: a windstorm.
• 16:16
  Speaker 3: That sounds completely impossible.
• 16:18
  Speaker 2: It's extremely difficult. You have to spend massive amounts of
• 16:21
  Speaker 2: energy and engineering just to isolate the system from the environment.
• 16:25
  Speaker 3: So to make quantum computing viable on a global scale,
• 16:28
  Speaker 3: we have to figure out a way to make the
• 16:30
  Speaker 3: playing cards windproof.
• 16:32
  Speaker 2: Exactly.
• 16:33
  Speaker 3: And that brings us back to our E over 4 quasi-particle.
• 16:37
  Speaker 3: How does splitting a charge fix the windstorm?
• 16:40
  Speaker 2: Well, the presence of this specific one-quarter charge strongly suggests
• 16:45
  Speaker 2: that the quasi-particles in the one-half state might possess an
• 16:48
  Speaker 2: incredibly exotic property.
• 16:50
  Speaker 3: What kind of property?
• 16:52
  Speaker 2: They might be what physicists call non-abelian anions.
• 16:56
  Speaker 3: Non-abelian anions. Okay, let's break down the difference between how
• 17:01
  Speaker 3: standard memory works and how non-abelian memory could completely change
• 17:04
  Speaker 3: data storage.
• 17:05
  Speaker 2: Okay, let's do it.
• 17:06
  Speaker 3: If a standard computer or even a normal quantum computer
• 17:09
  Speaker 3: stores data, it stores it locally. It places the information
• 17:12
  Speaker 3: in a single specific point.
• 17:15
  Speaker 2: Right. The information is tied to the exact state of
• 17:17
  Speaker 2: a localized particle.
• 17:18
  Speaker 3: It's kind of like writing your most important password on
• 17:21
  Speaker 3: a delicate glass bead. If a hammer, or in the
• 17:24
  Speaker 3: quantum world, a wave of thermal noise, hits that exact bead,
• 17:28
  Speaker 3: the bead shatters.
• 17:29
  Speaker 2: And the information is instantly destroyed.
• 17:31
  Speaker 3: It's gone forever because it existed in only one vulnerable place.
• 17:35
  Speaker 2: But a non-abelian state bypasses that vulnerability entirely, right?
• 17:38
  Speaker 1: It does.
• 17:39
  Speaker 2: It does not store information in a single local point. Instead...
• 17:44
  Speaker 2: It stores the information in the global overarching topology of
• 17:47
  Speaker 2: the system.
• 17:48
  Speaker 3: Global topology can sound really dense, but think of it
• 17:52
  Speaker 3: as taking a piece of string and tying it into
• 17:54
  Speaker 3: a complex knot. The knot represents your data.
• 17:56
  Speaker 2: I love that analogy.
• 17:57
  Speaker 3: Right. If a burst of local quantum noise comes along
• 18:00
  Speaker 3: and frays a tiny piece of the string on the
• 18:02
  Speaker 3: far edge, the knot itself doesn't disappear.
• 18:04
  Speaker 2: Exactly. The information survives because the geometry of the whole
• 18:08
  Speaker 2: system holds it together. The data isn't in the material
• 18:11
  Speaker 2: of the string. It's encoded in how the string is woven.
• 18:15
  Speaker 3: That's wild. So if these quasi-particles are truly non-abelian, it
• 18:19
  Speaker 3: means that simply by moving these particles around each other
• 18:22
  Speaker 3: in a specific order, essentially braiding their paths through space
• 18:26
  Speaker 3: and time, we can weave quantum information into unbreakable computational knots.
• 18:31
  Speaker 2: That's the dream. A topological quantum computer built out of
• 18:34
  Speaker 2: these non-abelian states wouldn't need massive, complex error correction systems.
• 18:39
  Speaker 3: Because it's fundamentally stable.
• 18:41
  Speaker 1: Right.
• 18:41
  Speaker 2: It would be inherently error-free at the hardware level. The
• 18:45
  Speaker 2: environmental windstorm could blow all it wants, but those computational
• 18:49
  Speaker 2: knots just won't untie.
• 18:51
  Speaker 3: So this gallium arsenide breakthrough is critical because the nu
• 18:54
  Speaker 3: equals one half state is thought to be only the
• 18:57
  Speaker 3: second known state in this material to possess these special
• 19:01
  Speaker 3: non-abelian properties.
• 19:02
  Speaker 1: Yes.
• 19:03
  Speaker 2: And because it survives at a few kelvins, it's slightly
• 19:06
  Speaker 2: more robust for extreme lab conditions. It actually transitions from
• 19:10
  Speaker 2: a theoretical concept to a viable candidate for building the
• 19:13
  Speaker 2: actual foundation of tomorrow's processors.
• 19:16
  Speaker 3: Which means the potential applications are completely world altering. We're
• 19:20
  Speaker 3: talking about designing pharmaceutical drugs atom by atom, simulating complex
• 19:24
  Speaker 3: climate models with flawless precision.
• 19:26
  Speaker 2: And cracking cryptographic codes that current technology couldn't break in millennia.
• 19:31
  Speaker 3: It really is a roadmap to the future. But as
• 19:34
  Speaker 3: with any map at the edge of known science, we
• 19:36
  Speaker 3: have to acknowledge where we actually are on the path
• 19:39
  Speaker 3: right now.
• 19:39
  Speaker 2: That's fair. There is a crucial scientific reality check required here.
• 19:44
  Speaker 3: Okay, bring us back down to Earth.
• 19:47
  Speaker 2: Measuring the exact E over 4 charge is a monumental achievement.
• 19:51
  Speaker 2: The unprecedented precision between the EPFL and Wiseman Labs is
• 19:55
  Speaker 2: beautiful science, but it remains a supporting piece of evidence.
• 20:01
  Speaker 3: It's the smoking gun, but not the bullet itself?
• 20:04
  Speaker 2: Well said. It strongly supports the theoretical models that predict
• 20:08
  Speaker 2: these quasi-particles have non-abelium properties. However, measuring the fractional charge
• 20:14
  Speaker 2: does not definitively prove that they can be braided. Ah, okay.
• 20:19
  Speaker 3: So we still have to tie the knot.
• 20:21
  Speaker 2: Exactly. The hunt is still fiercely on to directly observe
• 20:25
  Speaker 2: and confirm those global geometric behaviors. We've engineered the right conditions,
• 20:30
  Speaker 2: we've isolated the anomaly, and we've measured the impossible charge. Now,
• 20:35
  Speaker 2: we just have to prove we can actually braid them.
• 20:38
  Speaker 3: We are watching the real-time pursuit of manipulating the very
• 20:41
  Speaker 3: building blocks of reality. Scientists are forcing electrons to abandon
• 20:45
  Speaker 3: their fundamental individuality and merge into synchronized waves, all so
• 20:49
  Speaker 3: we can harness the exotic, rule-breaking properties that emerge from
• 20:53
  Speaker 3: that collective dance.
• 20:54
  Speaker 2: It's a massive leap forward.
• 20:55
  Speaker 3: It really is. We are not just observing the universe anymore.
• 20:59
  Speaker 3: We are learning how to rewrite its deepest mechanics. And
• 21:03
  Speaker 3: it leaves a lingering thought for you to consider. If
• 21:06
  Speaker 3: manipulating the microscopic space between frozen, magnetically squeezed particles allows
• 21:11
  Speaker 3: us to weave unbreakable computational knots, what other impossible rules
• 21:15
  Speaker 3: of physics are just waiting for the exact right extreme
• 21:18
  Speaker 3: conditions to be broken? And how might those shattered rules
• 21:22
  Speaker 3: reshape the boundaries of human technology tomorrow? Because honestly, if
• 21:26
  Speaker 3: a basic, indivisible penny can be split into quarters, you
• 21:29
  Speaker 3: have to wonder what else we have been entirely wrong about.