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Quantum Weirdness to World-Changing Tech · The Quark Side - Quantum Physics Podcast

0:01
Speaker 1: Welcome to the quark 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 at the smallest scales.
0:27
Speaker 2: Okay, so let's start with a box. A box, Yeah,
0:31
Speaker 2: the box. I know you've heard the story a thousand times,
0:34
Speaker 2: but we have to start here. Right inside this box,
0:37
Speaker 2: there's a.
0:37
Speaker 3: Cat and a pretty grim little device.
0:40
Speaker 2: Oh it's diabolical, A single radioactive atom that might decay,
0:44
Speaker 2: a Geiger counter to detect it, and a hammer that,
0:48
Speaker 2: if triggered, smashes a vial of poison.
0:50
Speaker 3: It is probably the most famous and definitely the most
0:53
Speaker 3: morbid thought experiment in all of science exactly.
0:56
Speaker 2: And the punchline, the thing everyone kind of knows is
0:58
Speaker 2: that until you open that box, the atom is in
1:01
Speaker 2: this weird state of both decayed and not decayed, a superposition,
1:05
Speaker 2: so the poison is both released and not released.
1:08
Speaker 3: Yeah.
1:08
Speaker 2: And the cat, well, the cats somehow simultaneously alive and dead.
1:12
Speaker 3: Schrodinger's cat, that's the poster child for quantum mechanics. Is weird.
1:16
Speaker 2: It really is, and for decades, I mean That's all
1:18
Speaker 2: it was, wasn't It was like a philosophical party trick,
1:21
Speaker 2: something to highlight the absurdity of it all it was.
1:23
Speaker 3: It was a paradox, to show that the rules of
1:25
Speaker 3: the tiny quantum world made no sense when you scaled
1:28
Speaker 3: them up to our world, the cats and boxes.
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Speaker 2: It felt like an abstraction, something for physicists to argue
1:34
Speaker 2: about on.
1:34
Speaker 3: A blackboard, right, not for the real world.
1:37
Speaker 2: But and this is the whole point of our conversation
1:39
Speaker 2: today on February second, twenty twenty six, that's not the
1:43
Speaker 2: story anymore. That idea that it's just a weird puzzle,
1:46
Speaker 2: it's outdated.
1:47
Speaker 3: It's completely changed. We've gone from the blackboard to well,
1:51
Speaker 3: the motherboard.
1:51
Speaker 2: Yeah, we're not talking about a hypothetical cat anymore. We
1:54
Speaker 2: are talking about the invisible engine powering I mean pretty
1:58
Speaker 2: much the entire modern world. The weirdness isn't a bug.
2:03
Speaker 2: It turns out it's the operating system.
2:05
Speaker 3: That's a perfect way to put it.
2:06
Speaker 2: And what's prompting This is a brand new piece that
2:08
Speaker 2: just came out in the journal Science. It's a perspective
2:11
Speaker 2: by doctor Marlin Scully and the title just says it all.
2:15
Speaker 2: Its started with a cat how one hundred years of
2:18
Speaker 2: quantum weirdness powers today's tech.
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Speaker 3: And we should say doctor Scully is the perfect person
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Speaker 3: to be writing this. He's not just a historian here.
2:26
Speaker 3: He's a major figure in the field. Who is He's
2:28
Speaker 3: a distinguished professor at Texas A and M. He's got
2:31
Speaker 3: an affiliation with Princeton. I mean, if you study quantum optics,
2:35
Speaker 3: you've probably read his textbook. He's one of the people
2:38
Speaker 3: who helped build the bridge from the old strange theory
2:43
Speaker 3: to the new practical applications.
2:45
Speaker 2: So he's seen the whole transition.
2:47
Speaker 3: He's lived it, he's helped cause it.
2:50
Speaker 2: Okay, so our mission today is to trace that journey.
2:53
Speaker 2: We're going to go back one hundred years to when
2:56
Speaker 2: the smartest people on the planet.
2:57
Speaker 3: Were just baffled, completely baffled.
3:00
Speaker 2: And bring it forward to today where we use that
3:02
Speaker 2: bafflement to build things that honestly feel a lot like magic.
3:06
Speaker 3: And we're going to break it down. We're not just
3:08
Speaker 3: going to list a bunch of gadgets. We want to
3:09
Speaker 3: get into the why. We'll talk about a concept called coherence,
3:13
Speaker 3: which is the secret behind every laser. Okay, we'll dive
3:16
Speaker 3: into entanglement, the spooky connection that Einstein hated, but that
3:20
Speaker 3: now protects your bank account.
3:22
Speaker 2: And you mentioned it even gets into what breaking the
3:24
Speaker 2: rules of engines.
3:25
Speaker 3: Breaking the classical rules. Yeah, we'll look at how quantum
3:28
Speaker 3: mechanics is pushing the limits of energy efficiency, and then
3:31
Speaker 3: we'll get into some really unexpected.
3:33
Speaker 2: Places like biology and weather forecasting. I saw that on
3:37
Speaker 2: the outline and it just seemed out of left field.
3:39
Speaker 3: It is, But that's how deep this goes. Now. It's everywhere.
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Speaker 2: So if you want to understand the phone in your hand,
3:44
Speaker 2: the Internet, even the future of medicine, you kind of
3:47
Speaker 2: have to understand the cat.
3:48
Speaker 3: You have to start with the cat.
3:49
Speaker 2: All right, let's do it. Rewind the clock for us,
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Speaker 2: take us back to the nineteen twenties. What did the
3:54
Speaker 2: world of physics feel like then.
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Speaker 3: In a word, chaos, complete intellectual crisis.
4:01
Speaker 2: Really, I always pictured these confident guys in tweed jackets.
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Speaker 3: Well, maybe in nineteen hundred they were confident. At the
4:08
Speaker 3: turn of the century, there was this feeling that physics
4:10
Speaker 3: was basically done.
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Speaker 2: The end of science idea exactly.
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Speaker 3: You had Newton's laws for gravity and motion, you had
4:17
Speaker 3: Maxwell's equations for light and electricity. You had thermodynamics. Lord
4:23
Speaker 3: Kelvin famously said there was nothing new left to discover,
4:26
Speaker 3: just more and more precise measurements.
4:27
Speaker 2: Wow was he wrong.
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Speaker 3: He was spectacularly wrong, because as soon as they started
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Speaker 3: probing the atom, the whole thing fell apart. All those
4:36
Speaker 3: beautiful classical rules just broke.
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Speaker 2: Give me an example, what's the first big crack that
4:41
Speaker 2: appears the electron?
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Speaker 3: Okay, so we know an atom has a nucleus in
4:45
Speaker 3: the middle and electrons buzzing around it. The simple picture
4:48
Speaker 3: is a tiny solar.
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Speaker 2: System, right, planets orbiting the Sun.
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Speaker 3: But an electron is a charged particle, and classical physics
4:57
Speaker 3: Maxwell's equations are very clear about this. A charged particle
5:01
Speaker 3: moving in a circle has to radiate energy, it has
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Speaker 3: to give off light. Okay, so if it's constantly losing energy,
5:07
Speaker 3: it should slow down, its orbit should decay, and in
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Speaker 3: a fraction of a second, every electron should spiral into
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Speaker 3: the nucleus, which would mean every atom in the universe
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Speaker 3: should instantly collapse. Matters shouldn't exist. You meet this table,
5:21
Speaker 3: none of it. So clearly something was deeply wrong with
5:24
Speaker 3: the old rules.
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Speaker 2: The theory predicted. We shouldn't be here to discuss the theory.
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Speaker 3: Pretty much bit of a problem.
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Speaker 2: So who rides to the rescue first. This is where
5:31
Speaker 2: Neil's Bore comes in, right.
5:33
Speaker 3: Yes, Neil's Bore from Denmark. He comes along and proposes this. Well,
5:39
Speaker 3: it was a radical idea. He basically just said the
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Speaker 3: old rules don't apply.
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Speaker 2: He just declared it.
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Speaker 3: He did. He proposed his model, the one we all
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Speaker 3: drew in high school chemistry, the little solar system with
5:50
Speaker 3: fixed rings.
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Speaker 2: Yeah, the nucleus and then shells for the electrons, right, and.
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Speaker 3: He said electrons can only exist in these specific shells,
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Speaker 3: these allowed orbits. They can't be in between. They can
6:00
Speaker 3: jump from one shell to another, but they can't spiral
6:02
Speaker 3: in Why not? He didn't really have a deep why.
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Speaker 3: His answer was basically, because if they did, Adams wouldn't exist,
6:08
Speaker 3: and they clearly do. It was a brilliant patch. It
6:11
Speaker 3: was a band aid that stopped the bleeding, and it
6:13
Speaker 3: worked remarkably well for explaining why Adams emit light in
6:17
Speaker 3: very specific colors.
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Speaker 2: So it was a good description, but not a fundamental
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Speaker 2: explanation exactly.
6:22
Speaker 3: It's set the stage, but the next step, the search
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Speaker 3: for the real why is where the drama really kicks in.
6:28
Speaker 3: This is the big clash of the nineteen twenties.
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Speaker 2: This is Schrodinger versus Heisenberg.
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Speaker 3: The ultimate physics showdown. And they had completely different approaches
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Speaker 3: to the problem. I mean fundamentally different philosophies.
6:38
Speaker 2: Okay, lay it out. Who's in the first corner.
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Speaker 3: In the first corner, you have the let's say, the
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Speaker 3: more traditional intuitive thinker, Erwin Schrodinger, the cat guy himself,
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Speaker 3: the very same. He looked at the electron and said, look,
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Speaker 3: maybe this whole kind of little ball idea is wrong.
6:56
Speaker 3: What if the electron isn't a particle at all? What
6:59
Speaker 3: if it's a wave, a wave of a wave of probability,
7:02
Speaker 3: a kind of smear of existence. He came up with
7:05
Speaker 3: the famous shrewding your equation, which describes the electron perfectly
7:10
Speaker 3: as a wave function. And a lot of physicists love this.
7:14
Speaker 3: Why because we can picture waves. You can imagine a
7:16
Speaker 3: ripple on a pond. It felt comfortable, it felt like
7:19
Speaker 3: something you could visualize.
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Speaker 2: It's intuitive. Okay, it's not a hard little dot, it's
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Speaker 2: a fuzzy cloud.
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Speaker 3: I think that. But in the other corner you have
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Speaker 3: the young radical Werner. Heisenberg, the abstract guy, the completely
7:30
Speaker 3: abstract guy. He looked at the data, which were these
7:33
Speaker 3: tables of numbers about how atoms absorbed in emitted light,
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Speaker 3: and he basically said, I don't care about your pictures.
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Speaker 3: I don't care about your intuitive waves. All that matters
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Speaker 3: is the math that predicts the experimental results.
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Speaker 2: So you just focused on the numbers.
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Speaker 3: Only the numbers. He developed something called matrix mechanics, which was,
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Speaker 3: I mean, it's just pure abstract linear algebra. Tables, numbers
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Speaker 3: going in, tables, numbers coming out, no orbits, no waves,
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Speaker 3: nothing to picture in your head.
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Speaker 2: And I'm guessing these two cams did not get along.
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Speaker 3: They hated each other's theories, I mean truly. Schrodinger called
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Speaker 3: Heisenberg's math repulsive and monstrous. Wow. And Heisenberg thought Schrodinger's
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Speaker 3: wave idea was I think the quote is sentimental trash.
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Speaker 3: He thought it was a cowardly attempt to stuff the
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Speaker 3: weird new quantum reality back into an old classical box.
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Speaker 2: It sounds like an argument between an artist and an
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Speaker 2: accountant over how to describe a painting.
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Speaker 3: That's a fantastic analogy. One is talking about the feeling
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Speaker 3: in the form the others talking about the pigment codes
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Speaker 3: and the canvas dimensions.
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Speaker 2: So who won?
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Speaker 3: That's the amazing part. They both did. It was eventually
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Speaker 3: proven that their two different mathematical formalisms were actually identical.
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Speaker 2: There were just two different languages describing the exact same.
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Speaker 3: Thing precisely, and the merger of those ideas that's what
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Speaker 3: gave us modern quantum field theory, the single most successful,
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Speaker 3: most precisely tested theory in the entire history of science.
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Speaker 2: But in this is the key point from doctor Scully's article.
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Speaker 2: For a long long time, this was all just about
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Speaker 2: describing things. It was about explaining why the atom doesn't collapse.
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Speaker 3: Yes, it was passive. We were observers. We were looking
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Speaker 3: at the quantum world and saying, wow, isn't that weird.
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Speaker 3: Let's write down the math for the weirdness.
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Speaker 2: But the big shift, the centennial we're sort of celebrating here,
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Speaker 2: is moving from observation to what application utilization.
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Speaker 3: We stopped just looking at the electron and we started
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Speaker 3: putting it to work. As Kelly says in his piece,
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Speaker 3: it started as a way to explain tiny particles, but
9:31
Speaker 3: now it's driving innovations that were just I mean, they
9:34
Speaker 3: were unimaginable the generation to go.
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Speaker 2: So we took the weirdness, the stuff that made them
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Speaker 2: all argue, the paradoxes, all of it.
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Speaker 3: The uncertainty, the superposition, the spookiness.
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Speaker 2: And we realized they weren't problems, they were features.
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Speaker 3: They were tools, the best tools nature ever gave us.
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Speaker 2: Okay, so let's get into those tools. Doctor Scully breaks
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Speaker 2: it down into three big concepts. Let's start with the
9:54
Speaker 2: first one. Coherence. I have to admit when I hear
9:57
Speaker 2: that word, I just think of an argument that makes sense.
10:00
Speaker 2: I don't think physics.
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Speaker 3: It's a fair point. Yeah, But in physics, coherence is
10:04
Speaker 3: really about synchronization harmony.
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Speaker 2: Okay.
10:10
Speaker 3: To get it, you have to first picture what normal
10:13
Speaker 3: everyday light is like. Think about a regular old incandescent
10:17
Speaker 3: light bulb.
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Speaker 2: Okay, got it. It's on, it's giving off light.
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Speaker 3: But at the atomic level, inside that filament, it's absolute chaos.
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Speaker 3: The atoms are hot, they're jiggling around randomly. One atom
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Speaker 3: spits out a photon, a particle of light going left.
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Speaker 3: A nanosecond later, another one spits when out going right,
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Speaker 3: and they're.
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Speaker 2: All different colors, lightly exactly.
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Speaker 3: Different phases, different directions, different frequencies. The light waves are
10:38
Speaker 3: all jumbled up and out of sink. It's noise.
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Speaker 2: It's like a huge crowd of people all talking at once.
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Speaker 3: That's the perfect analogy. It's a noisy, disorganized crowd that
10:48
Speaker 3: is incoherent light.
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Speaker 2: So what's coherent light?
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Speaker 3: Coherent light is when you somehow manage to grab every
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Speaker 3: single one of those atoms and force them to do
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Speaker 3: the exact same thing at the exact same time.
11:00
Speaker 2: Turn the crowd into a choir.
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Speaker 3: A perfectly disciplined, perfectly synchronized choir. Every single light wave
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Speaker 3: is marching in lockstep, same frequency, same phase, same direction.
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Speaker 3: The peaks of the waves lineup, the troughs of the
11:12
Speaker 3: waves lineup.
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Speaker 2: And when you do that, what do you get.
11:14
Speaker 3: You don't get a light bulb, You get a laser.
11:16
Speaker 2: The laser. It's funny it lasers feel so normal now
11:19
Speaker 2: they're in barcode scanners. My cat chase is a laser pointer.
11:22
Speaker 2: It feels like old tech.
11:23
Speaker 3: It's totally ubiquitous. Yeah, but we can't lease sight of
11:26
Speaker 3: how completely impossible it seemed. I mean, when the idea
11:29
Speaker 3: was first proposed based on an insight from Einstein, a
11:32
Speaker 3: lot of top physicists said it was practically impossible.
11:35
Speaker 2: Why what was the barrier?
11:37
Speaker 3: They just thought that nature's tendency towards disorder, towards chaos,
11:42
Speaker 3: towards that noisy crowd would always win. They didn't think
11:45
Speaker 3: you could ever impose that much quantum order on a
11:47
Speaker 3: real world system.
11:48
Speaker 2: But we did.
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Speaker 3: We did in nineteen sixty. And that coherence, that order
11:53
Speaker 3: is what gives a laser. It's almost magical properties because
11:56
Speaker 3: all the waves are working together. The beam is incredibly intense,
12:00
Speaker 3: and it doesn't spread out like light from a flashlight.
12:03
Speaker 2: It stays in a tight straight line.
12:04
Speaker 3: A phenomenally tight line. I mean, we literally bounce lasers
12:08
Speaker 3: off of reflectors that the Apollo astronauts left on the
12:10
Speaker 3: Moon to measure the Earth Moon distance down to the millimeter.
12:14
Speaker 3: You can't do that with a flashlight.
12:15
Speaker 2: Okay, that's impressive, But what about the everyday stuff. Scully mentions, Well, the.
12:19
Speaker 3: Barcode scanner is the most famous, simple one, but think bigger.
12:23
Speaker 3: Think about medicine, a lis I searcher. Exactly, we are
12:27
Speaker 3: using a blade made of pure coherent light to reshape
12:31
Speaker 3: the human cornea, to vaporize tissue with microscopic precision that
12:35
Speaker 3: is only possible because of quantum coherence.
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Speaker 2: Or what about the Internet itself? The whole thing runs
12:40
Speaker 2: on fiber optic.
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Speaker 3: Billions of miles of glass fiber with pulses of coherent
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Speaker 3: laser light flashing through them. Well, carrying this conversation right now,
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Speaker 3: all of human knowledge flying around the globe is ordered photons.
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Speaker 2: It's mind boggling that the solution to that nineteen twenties
12:55
Speaker 2: argument about waves and particles is the reason I can
12:58
Speaker 2: stream a movie.
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Speaker 3: That's pillar number one one. We learned how to tame
13:02
Speaker 3: the quantum wave.
13:03
Speaker 2: Okay, pillar one, coherence gives us the laser. Let's move
13:07
Speaker 2: to pillar two. And this is the one that it's weird.
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Speaker 3: Entanglement, spooky action at a distance.
13:13
Speaker 2: I love that Einstein said that it sounds so unscientific.
13:16
Speaker 2: He just called it spooky.
13:18
Speaker 3: It shows you how much it bothered him. I mean,
13:20
Speaker 3: Einstein was a firm believer in what's called locality mean
13:24
Speaker 3: meaning that if you want to affect something over there,
13:26
Speaker 3: you have to go over there and touch it, or
13:27
Speaker 3: you have to send something a baseball, a sound wave,
13:30
Speaker 3: a beam of light to interact with it, and nothing, nothing,
13:34
Speaker 3: can travel faster than.
13:35
Speaker 2: Light, the cosmic speed limit.
13:37
Speaker 3: The absolute speed limit. But quantum mechanics predicted something that
13:40
Speaker 3: seemed to violate this. It predicted that you could create
13:43
Speaker 3: two particles, say two photons, in a special linked state,
13:48
Speaker 3: an entangled state.
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Speaker 2: What does that mean linked?
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Speaker 3: It means they no longer have separate identities. They were
13:54
Speaker 3: described by a single shared wave function, a single mathematical reality,
13:59
Speaker 3: even if they're physically separated.
14:01
Speaker 2: So they're like one object in two different places.
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Speaker 3: That's a good way to think about it. Their properties
14:05
Speaker 3: are correlated in a way that classical physics just forbids.
14:09
Speaker 3: So let's do the classic example. You create a pair
14:11
Speaker 3: of entangled photons. You send one to Alice in New York.
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Speaker 2: And the other to Bob on Mars.
14:16
Speaker 3: Let's go with Mars. Sure, Alice and Bob. So while
14:19
Speaker 3: these photons are in flight, their properties are undefined. Let's
14:23
Speaker 3: talk about their polarization, like the orientation of the light wave.
14:27
Speaker 3: It's not horizontal or vertical. It's in a superposition of both,
14:31
Speaker 3: a cloud of possibility.
14:33
Speaker 2: Okay, so it's undecided, right.
14:35
Speaker 3: But the instant, and I mean the absolute instant that
14:38
Speaker 3: Alice in New York measures her photon and her detectors
14:41
Speaker 3: as vertical. She knows with one hundred percent certainty that
14:46
Speaker 3: Bob's photon on Mars, millions of miles away, has instantly
14:49
Speaker 3: resolved itself into the horizontal state.
14:51
Speaker 2: Instantly, not in the time it would take for a
14:54
Speaker 2: light signal to travel from here to Mars.
14:56
Speaker 3: Faster than that, infinitely faster, it seems. The collapse of
15:01
Speaker 3: the wave function appears to be instantaneous across any distance.
15:05
Speaker 2: I can see why Einstein called that spooky.
15:07
Speaker 3: He hated it. He thought it meant the theory had
15:10
Speaker 3: to be incomplete. He argued, there must be some hidden variables,
15:13
Speaker 3: like secret instructions the particles were carrying with them from
15:16
Speaker 3: the start.
15:17
Speaker 2: Like they flipped a coin before they left, and agreed, okay,
15:19
Speaker 2: if she asks your vertical, and I'm horizontal exactly.
15:23
Speaker 3: He thought it was a conspiracy, not a real connection.
15:26
Speaker 3: But here's the amazing thing. We've done the experiments. Yeah,
15:31
Speaker 3: over and over, and Einstein was wrong.
15:34
Speaker 2: There are no secret instructions.
15:36
Speaker 3: Nope, the spooky connection is real. The universe is non local.
15:41
Speaker 3: It's just a fact.
15:42
Speaker 2: Okay, So the universe is weirder than Einstein was comfortable with.
15:45
Speaker 2: We've established that, but how do we use this? What's
15:47
Speaker 2: the application?
15:48
Speaker 3: The number one application right now is cryptography keeping secrets safe?
15:52
Speaker 2: Okay, so digital security.
15:53
Speaker 3: Think about it. Our entire global economy, our military secrets
15:57
Speaker 3: are personal data. It's all part by encryption, and that
16:02
Speaker 3: encryption is based on math problems that are really really
16:06
Speaker 3: hard to solve.
16:06
Speaker 2: Like factoring huge numbers.
16:08
Speaker 3: Right, but really hard isn't the same as impossible. A
16:12
Speaker 3: powerful enough computer, say a future quantum computer, could potentially
16:17
Speaker 3: crack our current encryption methods.
16:19
Speaker 2: So all our secrets would be out in the open potentially.
16:22
Speaker 3: Yes, it's a huge concern. But entanglement offers a way out.
16:26
Speaker 3: It allows you to create an encryption key that isn't
16:28
Speaker 3: just mathematically hard to break, it's physically impossible to copy
16:32
Speaker 3: or even listen to without being detected.
16:34
Speaker 2: How does that work?
16:35
Speaker 3: Okay, So imagine Alice wants to send a secret key
16:38
Speaker 3: to Bob. Instead of sending a string of ones and zeros,
16:41
Speaker 3: she sends as free of entangled photons. Now, an evesdropper
16:45
Speaker 3: we'll call her Eve tries to intercept the message.
16:47
Speaker 2: She taps the fiber optic cable, right.
16:50
Speaker 3: But to find out the state of the photon. What
16:51
Speaker 3: does Eve have to do.
16:53
Speaker 2: She has to measure it.
16:54
Speaker 3: She has to measure it. And in quantum mechanics, the
16:56
Speaker 3: active measurement isn't passive. It changes the system. The moment
17:01
Speaker 3: ease detector interacts with that photon, it collapses the wave function,
17:05
Speaker 3: it breaks the entanglements. Sees the fingerprint a giant unmissible fingerprint.
17:10
Speaker 3: Alice and Bob can then sacrifice a small part of
17:13
Speaker 3: their key, compare notes over a public channel, and if
17:16
Speaker 3: they see a bunch of errors that shouldn't.
17:18
Speaker 2: Be there, they know Eve was listening.
17:19
Speaker 3: They know instantly they throw away the compromise key and
17:22
Speaker 3: start over. It's like a security system that's guaranteed by
17:26
Speaker 3: the fundamental laws of physics.
17:27
Speaker 2: It's like a message written in invisible ink that bursts
17:30
Speaker 2: into flame if anyone but the intended reader tries to
17:33
Speaker 2: look at it.
17:33
Speaker 3: That's a perfect way to put it. And this is
17:35
Speaker 3: in science fiction. Governments are building quantum communication networks. There's
17:39
Speaker 3: a Chinese satellite called Mishis that does this from space.
17:42
Speaker 3: We are building the foundations of a quantum internet.
17:45
Speaker 2: That's wild, but the source mentions another use for entanglement
17:49
Speaker 2: that's bigger. LEGO.
17:52
Speaker 3: Yes, the Laser Interferometer Gravitational Wave Observatory.
17:55
Speaker 2: These are the giant detectors that discovered gravitational waves, the
17:59
Speaker 2: ripples in SIE spacetime from colliding black holes.
18:01
Speaker 3: That's the one. And what they're trying to measure is
18:04
Speaker 3: almost impossibly small. A gravitational wave passing through Earth stretches
18:10
Speaker 3: and squeezes everything by a distant smaller than the width
18:13
Speaker 3: of a proton.
18:14
Speaker 2: How can you possibly measure that a truck driving by
18:17
Speaker 2: a mile away must shake the ground more than that it.
18:20
Speaker 3: Does, which is why the detectors are so isolated. But
18:24
Speaker 3: even with perfect isolation, there's a fundamental limit. It's called
18:28
Speaker 3: quantum noise or shot noise.
18:30
Speaker 2: What's that.
18:30
Speaker 3: It's the fact that a laser beam, even a perfect one,
18:33
Speaker 3: isn't a smooth, continuous river of light. It's made of
18:36
Speaker 3: individual photons. It's like rain on a roof. There's a
18:40
Speaker 3: natural randomness, a statistical jitter to when the photons arrive
18:43
Speaker 3: with the detector.
18:44
Speaker 2: So the laser beam itself is noisy at the quantum.
18:47
Speaker 3: Level exactly, and that noise can be bigger than the
18:50
Speaker 3: tiny signal from the gravitational wave you're trying to hear.
18:52
Speaker 3: It's like trying to hear a pin drop during a hailstorm.
18:54
Speaker 2: So how does entanglement help these A.
18:56
Speaker 3: Very clever trick called squeezed light. It's a way of
19:00
Speaker 3: manipulating the Heisenberg uncertainty principle.
19:02
Speaker 2: Oh boy, okay, unpack that for me. Heisenberg says, you
19:06
Speaker 2: can't know certain pairs of things perfectly at the same time, right,
19:09
Speaker 2: Like a particle's position and its momentum exactly.
19:12
Speaker 3: There's a trade off. The more precisely you know its position,
19:15
Speaker 3: the fuzzier its momentum becomes, and vice versa. Well, a
19:19
Speaker 3: light wave also has pairs like that. It has an
19:22
Speaker 3: amplitude its brightness, and a phase where it is in
19:26
Speaker 3: its wave cycle. Okay, Using entangled photons, scientists can squeeze
19:30
Speaker 3: the uncertainty. They essentially say, we don't really care about
19:34
Speaker 3: the phase for this measurement, but we need to know
19:35
Speaker 3: the amplitude with insane precision. So they manipulate the quantum
19:39
Speaker 3: state to dump all the uncertainty into the phase.
19:42
Speaker 2: You're hiding the noise in a part of the light
19:44
Speaker 2: you're not looking at.
19:45
Speaker 3: You're sweeping the quantum dust under a rug. You don't
19:47
Speaker 3: care about. And the result is you get a laser
19:49
Speaker 3: beam whose brightness is quieter, more stable than quantum mechanics
19:53
Speaker 3: would normally allow.
19:54
Speaker 2: And that lets them here are the black holes.
19:56
Speaker 3: It boosts lego sensitivity significantly. We are listening to the
20:01
Speaker 3: echoes of cosmic collisions from billions of years ago by
20:04
Speaker 3: using a quantum trick that Einstein thought was just stooky nonsense.
20:09
Speaker 2: Okay, this is amazing. So coherence gives us the laser
20:13
Speaker 2: entanglement gives us secure codes and a way to listen
20:16
Speaker 2: to the cosmos. This brings us to the third big
20:19
Speaker 2: concept from Scully's paper, and this one, this one feels
20:23
Speaker 2: like it's breaking a really fundamental rule.
20:25
Speaker 3: There are dynamics the quantum heat engine.
20:28
Speaker 2: Right now, What I remember from physics class is that
20:30
Speaker 2: there's a hard limit, the Carno limit, named after some
20:34
Speaker 2: nineteenth century French engineer Setti Krno Yes, and he basically said,
20:37
Speaker 2: you can't build a perfect engine. You put heat in,
20:40
Speaker 2: you get workout, but you always always have waste heat
20:43
Speaker 2: left over. There's a maximum possible efficiency and you can't
20:46
Speaker 2: beat it.
20:47
Speaker 3: It's one of the most fundamental laws. You can't get
20:49
Speaker 3: something for nothing. And you can't even break even. There
20:51
Speaker 3: is no free lunch.
20:52
Speaker 2: But doctor Scully's work seems to suggest there's a.
20:55
Speaker 3: Loophole, a quantum loophole. Let's be very clear. We are
20:58
Speaker 3: not breaking the law of conservation of energy. We are
21:01
Speaker 3: not creating energy out of thin air.
21:04
Speaker 2: Okay, good, I was worried for a second.
21:05
Speaker 3: But what Scully and others have shown is that you
21:08
Speaker 3: can design an engine that operates with an efficiency greater
21:12
Speaker 3: than the classical carnolimit.
21:14
Speaker 2: How is that possible?
21:16
Speaker 3: It all comes back to coherence. Think about a regular engine,
21:19
Speaker 3: like a steam engine. The working fluid is hot gas,
21:23
Speaker 3: and those gas molecules are like trillions of tiny billiard
21:27
Speaker 3: balls all bouncing around randomly and chaotically. That chaos is
21:33
Speaker 3: a source of inefficiency.
21:34
Speaker 2: Disorganize energy exactly.
21:36
Speaker 3: You lose a lot just to that randomness. But what
21:39
Speaker 3: if your working fluid wasn't a bunch of random billiard balls.
21:43
Speaker 3: What if it was a collection of atoms prepared in
21:45
Speaker 3: a special quantum coherence state.
21:47
Speaker 2: You're using the choir again instead of the crowd.
21:50
Speaker 3: The choir's back. By using coherence, you can create correlations
21:53
Speaker 3: between the atoms that suppress some of that randomness, you
21:56
Speaker 3: could essentially channel the heat energy into useful work in
22:00
Speaker 3: a way that avoids the pathways that would normally lead
22:02
Speaker 3: to waste.
22:03
Speaker 2: So the kernel limit wasn't a fundamental law the universe.
22:05
Speaker 2: It was just a limit based on using dumb classical particles.
22:09
Speaker 3: It was a limit based on the assumptions of classical thermodynamics.
22:12
Speaker 3: When you introduce quantum information and quantum coherence into the system,
22:17
Speaker 3: you change the rules of the game. You're extracting useful
22:20
Speaker 3: work from a place that classical physics had written off
22:23
Speaker 3: as unavoidable waste.
22:25
Speaker 2: That feels like a massive deal for energy production down
22:28
Speaker 2: the line.
22:28
Speaker 3: It's a whole new frontier. We're not going to see
22:30
Speaker 3: quantum engines in our cars tomorrow, but it fundamentally changes
22:33
Speaker 3: our understanding of the relationship between information, energy, and work.
22:38
Speaker 3: As Kelly says, it's a striking example of how quantum
22:40
Speaker 3: principles can rewrite the rules of classical physics.
22:43
Speaker 2: It really is. Okay, I want to shift gears. Now,
22:46
Speaker 2: we've talked lasers, computing energy. This all feels like the
22:49
Speaker 2: traditional domain of physics, hard tech, but the source material
22:53
Speaker 2: then goes somewhere I did not see coming biology. Yeah,
22:56
Speaker 2: it's so strange. I mean, my mental image of a
22:59
Speaker 2: quantum experiment is a lab cool to a thousandth of
23:02
Speaker 2: a degree above absolute zero, a perfect vacuum, everything shielded.
23:06
Speaker 2: It feels incredibly fragile.
23:08
Speaker 3: That's generally true. The biggest enemy of quantum weirdness is
23:12
Speaker 3: the environment. It's a phenomenon called decoherence. The moment the
23:17
Speaker 3: outside world interacts with your delicate quantum state, it collapses.
23:21
Speaker 2: The magic vanishes, and a living thing, a cell, is
23:25
Speaker 2: the exact opposite of that. It's warm, it's wet, it's messy.
23:28
Speaker 2: It's the noisiest environment imaginable.
23:31
Speaker 3: And that's why, for a long time, the dogma among
23:34
Speaker 3: physicists was that quantum mechanics could play no meaningful role
23:37
Speaker 3: in biology. It's just too hot and wet for any
23:40
Speaker 3: of this delicate stuff to survive.
23:41
Speaker 2: But it seems that's wrong.
23:43
Speaker 3: It seems nature is a much better quantum engineer than
23:45
Speaker 3: we are.
23:46
Speaker 2: The article mentions a specific technology here. First, it's a
23:49
Speaker 2: mouthful coherent Raymond spectroscopy.
23:53
Speaker 3: It is, okay, let's just break it down. A Rayms
23:55
Speaker 3: spectroscopy on its own is a technique scientist used to
23:57
Speaker 3: identify molecules. You shine light on a sample. When a
24:01
Speaker 3: photon of light heads a molecule, it makes the molecule
24:03
Speaker 3: vibrate the chemical bond, stretch and wiggle, and that malibration
24:07
Speaker 3: steals a tiny bit of energy from the photon, which
24:10
Speaker 3: changes its color very slightly.
24:12
Speaker 2: And different molecules wiggle in different ways.
24:15
Speaker 3: Exactly, a sugar molecule has a different vibrational fingerprint than
24:19
Speaker 3: a protein or a lipid. So by looking at how
24:22
Speaker 3: the color of the light changes, you can figure out
24:24
Speaker 3: what chemicals are in your sample.
24:26
Speaker 2: Sounds useful. What's the problem.
24:27
Speaker 3: The signal is pathetically weak, only about one in a
24:30
Speaker 3: million photons, and you shine on the sample actually gets
24:34
Speaker 3: changed in this way. It's like trying to find one
24:36
Speaker 3: specific grain of sand on a beach.
24:38
Speaker 2: So how does adding coherent to the name help? You?
24:42
Speaker 3: Guessed it? It's the choir again. Instead of just shining
24:44
Speaker 3: a steady light, you use very fast, powerful laser pulses
24:48
Speaker 3: to force all the molecules of specific type, say, all
24:52
Speaker 3: the glucose molecules to start vibrating in perfect unison.
24:55
Speaker 2: You make the molecules sing together, and when.
24:57
Speaker 3: They sing together the signal they produce is amp by
25:00
Speaker 3: orders of magnitude. It goes from being a nearly invisible
25:03
Speaker 3: whisper to a shout.
25:05
Speaker 2: And what does that let you do?
25:06
Speaker 3: It lets you see biology happen in real time. The
25:09
Speaker 3: source mentions using it to map the chemical composition of
25:12
Speaker 3: a virus. At the nanoscale, you can watch a drug
25:15
Speaker 3: molecule binding to a receptor on a living cell. It
25:18
Speaker 3: gives us a window into the molecular machinery of life.
25:21
Speaker 3: That is just unprecedented.
25:23
Speaker 2: We're upgrading from a blurry photograph to a live four
25:26
Speaker 2: K video.
25:27
Speaker 3: That's a great way to put it. And it's not
25:29
Speaker 3: just a tool we're using. There's more and more evidence
25:31
Speaker 3: that life itself uses.
25:33
Speaker 2: These tricks, like in photosynthesis.
25:35
Speaker 3: That's the prime suspect for a plant to turn sunlight
25:38
Speaker 3: into chemical energy. That energy has to travel through a dense,
25:41
Speaker 3: messy forest of proteins inside the leaf. Classically, it should
25:46
Speaker 3: bounce around randomly and lose most of its power as
25:48
Speaker 3: waste heat, but it doesn't.
25:50
Speaker 2: It's super efficient.
25:51
Speaker 3: It's nearly one hundred percent efficient, and the thinking is
25:54
Speaker 3: that it uses quantum coherence. The energy travels as a wave,
25:58
Speaker 3: exploring all possible paths multaneously and instantly finds the most
26:02
Speaker 3: efficient route. It's performing a quantum search.
26:04
Speaker 2: So my houseplant is running a quantum algorithm in.
26:07
Speaker 3: A very real sense. Yes, it's humbling. We spend billions
26:11
Speaker 3: on building these sterile labs to do what a simple
26:13
Speaker 3: leaf does in the sunshine.
26:15
Speaker 2: That is incredible. Okay, So from the tiniest virus to
26:18
Speaker 2: a hurricane. The last application in the source is weather.
26:22
Speaker 3: In turbulence, the oldest unsolved problem in classical physics.
26:26
Speaker 2: I just think of it as something that makes my
26:28
Speaker 2: flight bumpy. I didn't realize it was a deep mystery.
26:30
Speaker 3: Oh it's a hunster.
26:31
Speaker 2: Yeah.
26:32
Speaker 3: Heisenberg is supposed to have said that when he died
26:34
Speaker 3: and met God, he was going to ask two questions,
26:37
Speaker 3: why relativity and why turbulence? And he said, I really
26:41
Speaker 3: believe he will have an answer for the first.
26:43
Speaker 2: So even Heisenberg thought turbulence was basically unsolvable.
26:46
Speaker 3: It's just too complex, the chaotic swirling motion of air
26:50
Speaker 3: or water. The equations that describe it are nightmareshly difficult.
26:53
Speaker 3: That's why even with supercomputers, our weather forecasts fall apart
26:56
Speaker 3: after a week or so.
26:57
Speaker 2: So where does quantum mechanics come in.
27:00
Speaker 3: Comes in by providing a simplified model system, a playground
27:03
Speaker 3: to study turbulence in a cleaner way. Scientists are looking
27:06
Speaker 3: at something called superfluid helium. Yeah, it's a bizarre state
27:10
Speaker 3: of matter. If you cool helium down to just a
27:12
Speaker 3: couple of degrees above absolute zero, it transforms. It loses
27:16
Speaker 3: all viscosity. It is zero friction.
27:18
Speaker 2: What does that mean.
27:19
Speaker 3: It means if you swirl it in a cup, it
27:21
Speaker 3: will literally never stop swirling. It can flow up the
27:24
Speaker 3: walls of a container. It's a quantum fluid where all
27:27
Speaker 3: the atoms are acting is one single coherent entity.
27:31
Speaker 2: That's strange, But how does that help with turbulence.
27:34
Speaker 3: In a normal fluid like air, turbulence is a chaotic
27:37
Speaker 3: mess of eddies and vortices of all different sizes. But
27:41
Speaker 3: in this quantum fluid, the rotation is quantized. It can
27:45
Speaker 3: only spin in discrete identical units, these tiny perfect tornadoes
27:49
Speaker 3: called quantum vortices.
27:50
Speaker 2: So it's organized chaos.
27:52
Speaker 3: It's countable chaos. You can study how these identical little
27:55
Speaker 3: vortices interact and tangle up to create turbulence on a
27:58
Speaker 3: larger scale. It's a much simple, cleaner problem than trying
28:01
Speaker 3: to model the entire.
28:02
Speaker 2: Atmosphere, and what you learned from the helium, you.
28:05
Speaker 3: Find mathematical patterns and scaling laws that, it turns out,
28:08
Speaker 3: also applied to the big, messy classical turbulence of our
28:11
Speaker 3: weather systems and the air flowing over an airplane wave.
28:14
Speaker 2: So we're making flights safer and improving storm forecasts by
28:18
Speaker 2: studying the weird behavior of super cold liquid helium.
28:23
Speaker 3: We are. It's this incredible through line. The same fundamental
28:26
Speaker 3: rules of quantum mechanics that describe that helium also describe
28:30
Speaker 3: photosynthesis and also describe the laser in your phone.
28:33
Speaker 2: It's all connected.
28:34
Speaker 3: It's all the same physics.
28:35
Speaker 2: Okay, so we've covered one hundred years. We started with
28:40
Speaker 2: the confusion, the fights. We've seen. Coherence give us lasers,
28:45
Speaker 2: entanglement give us security, and black hole detectors, and thermodynamics
28:49
Speaker 2: give us a new class of engines. We've even dipped
28:51
Speaker 2: into biology and the weather.
28:52
Speaker 3: It's been a busy century.
28:54
Speaker 2: But doctor Scully's paper it doesn't end there. It's not
28:57
Speaker 2: just a look back. He ends on a forward looking note.
29:00
Speaker 2: He says the adventure is just beginning.
29:02
Speaker 3: Which is absolutely true. For all we figured out. The
29:05
Speaker 3: list of what we don't know is still huge.
29:07
Speaker 2: What's at the top of that list, what's the biggest
29:09
Speaker 2: unsolved mystery?
29:10
Speaker 3: Gravity without a doubt?
29:12
Speaker 2: Still, after all this time.
29:14
Speaker 3: Still we have these two perfect theories. We have quantum mechanics,
29:18
Speaker 3: which describes the world of the very small with flawless precision,
29:23
Speaker 3: and we have Einstein's general relativity, his theory of gravity,
29:27
Speaker 3: which describes the world of the very large planets, stars, galaxies,
29:32
Speaker 3: also with flawless precision. That they don't work together, They
29:35
Speaker 3: hate each other. They're written in different mathematical languages, and
29:37
Speaker 3: they give nonsensical answers infinities when you try to apply
29:41
Speaker 3: them in the same place, like at the center of
29:43
Speaker 3: a black hole.
29:43
Speaker 2: So we don't know if gravity itself is a quantum force.
29:46
Speaker 3: We don't is there a quantum particle of gravity, a graviton.
29:50
Speaker 3: Is space time itself smooth and continuous, or is it
29:53
Speaker 3: made of tiny pixel like chunks at the smallest possible scale.
29:58
Speaker 3: We have ideas like string theory or loop quantum gravity,
30:02
Speaker 3: but we don't need answer yet.
30:03
Speaker 2: Unifying those two theories is the holy grail.
30:06
Speaker 3: It's the theory of everything that physicists have been dreaming
30:09
Speaker 3: about for a century.
30:10
Speaker 2: And what about the tech The big one we've only
30:12
Speaker 2: touched on is quantum computing.
30:13
Speaker 3: Right, that's where all of these principles superposition, entanglement come
30:18
Speaker 3: together in the ultimate application.
30:19
Speaker 2: So just too clear for everyone listening. What is the
30:22
Speaker 2: fundamental difference between the computer on your desk and a
30:25
Speaker 2: quantum computer.
30:27
Speaker 3: Your computer works with bits. A bit is a switch.
30:30
Speaker 3: It can be on or off, a one or a zero.
30:32
Speaker 3: It's binary. A quantum computer works with quibits, and thanks
30:38
Speaker 3: to superposition, the same principle as the cat being alive
30:41
Speaker 3: and dead, a quibit can be a one and a
30:43
Speaker 3: zero at the same.
30:44
Speaker 2: Time, so it's not one or the other. It's a
30:46
Speaker 2: blend of both exactly.
30:47
Speaker 3: And if you have two quibits, you can represent four
30:50
Speaker 3: states at once. Three quibits eight states. It scales exponentially.
30:54
Speaker 3: If you can build a quantum computer with just a
30:56
Speaker 3: few hundred stable.
30:57
Speaker 2: Quibits, you get this astronomical computing power. The source says
31:02
Speaker 2: they could solve problems in seconds that would take our
31:05
Speaker 2: best current supercomputer's.
31:06
Speaker 3: Millennia literally thousands or even millions of years. It's not
31:10
Speaker 3: just a faster version of what we have. It's a
31:12
Speaker 3: completely different way of computing.
31:14
Speaker 2: What kind of problem needs that kind of power.
31:16
Speaker 3: The biggest one is simulating reality itself. If you want
31:20
Speaker 3: to invent a new drug, you need to simulate how
31:23
Speaker 3: a complex molecule will fold and interact with proteins in
31:27
Speaker 3: the body. That's a quantum problem.
31:30
Speaker 2: And classical computers are bad at simulating quantum mechanics.
31:33
Speaker 3: They're terrible at it. It takes an insane amount of memory.
31:36
Speaker 3: It's like trying to build a perfect flight simulator using
31:39
Speaker 3: only lego. A quantum computer simulates quantum nature natively. It
31:46
Speaker 3: speaks the right language.
31:47
Speaker 2: So we could discover new medicines, design new materials for
31:51
Speaker 2: perfect solar cells or batteries, maybe even create truly accurate
31:55
Speaker 2: climate models.
31:56
Speaker 3: That's the promise a revolution in science and engineering.
32:00
Speaker 2: It really feels like we're just at the beginning, Like
32:01
Speaker 2: we've spent one hundred years learning the alphabet of the
32:04
Speaker 2: universe and now we're about to start writing sentences.
32:07
Speaker 3: I think that's a perfect metaphor. We know enough now
32:09
Speaker 3: to understand how much we still have to learn, which
32:12
Speaker 3: is a much better place to be than in nineteen
32:14
Speaker 3: hundred when they thought they knew everything.
32:16
Speaker 2: It's way more exciting. Okay, let's bring it all home.
32:19
Speaker 2: We have thrown a ton of concepts at people today,
32:22
Speaker 2: so let's do a quick sheet sheet. If you're at
32:24
Speaker 2: a party and want to sound smart, what are the
32:27
Speaker 2: five key ways quantum mechanics is already running your life?
32:30
Speaker 3: Right, Let's do it. Number one, lasers comes from quant coherence.
32:35
Speaker 3: It's in your phone, your Blu ray player, your Internet connection,
32:38
Speaker 3: the doctor's.
32:39
Speaker 2: Office, got it. Number two secure communication, that's entanglement, the
32:44
Speaker 2: future of unhackable data for banking, government, everything.
32:48
Speaker 3: Number three faster computing, well future computing using superposition to
32:53
Speaker 3: solve currently impossible problems in medicine, materials and beyond right.
32:58
Speaker 2: Number four better measurements using squeeze light and other quantum
33:02
Speaker 2: tricks to sense the world with incredible precision, from gravitational
33:06
Speaker 2: waves to maybe even tiny magnetic fields in the brain.
33:09
Speaker 3: And Number five medical breakthroughs using those spectroscopy techniques to
33:13
Speaker 3: see what's happening inside a single living cell to understand
33:16
Speaker 3: and fight disease at the most fundamental level.
33:18
Speaker 2: That is a hell of a resume for a theory
33:20
Speaker 2: that started with people getting angry about a.
33:22
Speaker 3: Cat in a box it is, And I think the
33:25
Speaker 3: real takeaway is that this stuff isn't magic. It feels
33:29
Speaker 3: like it, but it's just the real rules of the universe.
33:32
Speaker 3: We're just finally learning how to read the user manual.
33:35
Speaker 2: And like doctor Scully said, the adventure is just beginning.
33:38
Speaker 3: It makes you think, if the last century took us
33:42
Speaker 3: from that thought experiment to the smartphone and mapping black holes, what.
33:46
Speaker 2: On earth is the next one hundred years going to
33:48
Speaker 2: look like.
33:49
Speaker 3: Are we going to finally unify gravity? Are we going
33:53
Speaker 3: to understand dark matter?
33:54
Speaker 2: Are we going to be able to manipulate reality in
33:57
Speaker 2: ways that we can't even imagine?
33:58
Speaker 3: Right now, I've learned not to bet against the weirdness
34:01
Speaker 3: me neither.
34:02
Speaker 2: The universe is pretty good at blowing our minds.
34:04
Speaker 3: It certainly is.
34:05
Speaker 2: Well, that's all the time we have for this one.
34:07
Speaker 2: Thanks for diving into the quantum realm with us.
34:09
Speaker 3: It is a pleasure.
34:10
Speaker 2: Keep asking questions and we'll catch you on the next
34:13
Speaker 2: deep dive.