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Could the Universe Be Hiding Undetectable Quantum Matter? · 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 at the smallest scales.
• 0:27
  Speaker 2: I want you to imagine, just for a second, stepping
• 0:29
  Speaker 2: outside on a really crisp, clear night. You look up
• 0:35
  Speaker 2: and you see the night sky in all its glory.
• 0:37
  Speaker 3: Right, it's completely breathtaking here.
• 0:39
  Speaker 2: Yeah, you see the stars twinkling, maybe the faint smudge
• 0:43
  Speaker 2: of a distant galaxy, or the glowing dust of the
• 0:46
  Speaker 2: Milky Way stretching right across the horizon. It feels incredibly vast,
• 0:50
  Speaker 2: it really does. It feels like you are looking at
• 0:52
  Speaker 2: the entire universe. Yeah, but here is the mind bending reality.
• 0:57
  Speaker 2: Everything you can see, I mean everything emitting light, absorbing light,
• 1:00
  Speaker 2: or reflecting light. It's just a tiny microscopic fraction of
• 1:04
  Speaker 2: what is actually out there.
• 1:05
  Speaker 3: Yeah, it's wild. The vast, overwhelming majority of our universe
• 1:08
  Speaker 3: is completely invisible to our eyes and well to our
• 1:11
  Speaker 3: telescopes too, completely invisible. Exactly. We only know this unseen
• 1:15
  Speaker 3: matter exists because we can observe its gravity pulling on
• 1:19
  Speaker 3: the luminous structures, we actually can.
• 1:20
  Speaker 2: See, like, we can literally see its effects without seeing it.
• 1:24
  Speaker 3: Right. We watch galaxies rotating at speeds that you know,
• 1:27
  Speaker 3: frankly you should tear them apart, yet they hold together,
• 1:30
  Speaker 3: basically bound by the immense weight of this invisible scaffolding.
• 1:35
  Speaker 2: We are talking about dark matter, of course. It's the
• 1:38
  Speaker 2: universe's ultimate.
• 1:39
  Speaker 3: Ghost, the ultimate ghost, yeah, because it just.
• 1:41
  Speaker 2: Doesn't interact with electromagnetism at all. It drifts right through everything,
• 1:46
  Speaker 2: and for decades the physics community has been completely obsessed
• 1:50
  Speaker 2: with trying to catch it.
• 1:51
  Speaker 1: Oh.
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  Speaker 3: Absolutely, everyone wants to figure out what it is made of,
• 1:53
  Speaker 3: and you know, to detect it directly right here on Earth, which.
• 1:57
  Speaker 2: Is why we are currently living through this incredible boom
• 2:01
  Speaker 2: in quantum technology. Like physicists are building these hyper sensitive,
• 2:05
  Speaker 2: cutting edge quantum machines designed specifically to hunt for this
• 2:09
  Speaker 2: ghostly matter.
• 2:10
  Speaker 3: And that technological leap that's what sets the stage for
• 2:14
  Speaker 3: a really fascinating paradise paradox. Yeah, because a groundbreaking new
• 2:18
  Speaker 3: study analyzing how these detectors interact with dark matter has
• 2:22
  Speaker 3: revealed this profound cosmic irony.
• 2:25
  Speaker 2: Okay, I love a good cosmic irony.
• 2:27
  Speaker 3: Well, the fundamental quantum nature of dark matter is completely
• 2:30
  Speaker 3: fundamentally undetectable to us.
• 2:33
  Speaker 2: Wait really, yeah.
• 2:34
  Speaker 3: The universe is actively hiding its quantum mechanics from our machines.
• 2:38
  Speaker 2: Wow. Okay, so here is where we are going today.
• 2:42
  Speaker 2: We're going to explore the mechanics of why the universe
• 2:45
  Speaker 2: is burying its quantum secrets, how this massive realization actually works,
• 2:51
  Speaker 2: and why surprisingly this seemingly impassable wall is actually brilliant news.
• 2:57
  Speaker 3: It really is great news for science.
• 2:59
  Speaker 2: But to really grasp why the quantum nature of dark
• 3:03
  Speaker 2: matter is playing hide and seek with our most advanced technology,
• 3:07
  Speaker 2: we need to talk about what physicists actually think this
• 3:09
  Speaker 2: ghost is made of.
• 3:10
  Speaker 3: Right, We have to start with the suspects.
• 3:11
  Speaker 2: Exactly, because for a long time we've had a roster
• 3:14
  Speaker 2: of theoretical candidates.
• 3:15
  Speaker 3: We have because dark matter refuses to interact with normal
• 3:18
  Speaker 3: matter in any meaningful way, you basically have to build
• 3:21
  Speaker 3: theoretical models of particles that fit that extreme ghostly profile.
• 3:26
  Speaker 3: And one of the leading theoretical candidates right now is
• 3:29
  Speaker 3: a particle called the axion.
• 3:30
  Speaker 2: The axion, Okay, I know this is a front runner,
• 3:33
  Speaker 2: but how does it differ from the heavy bulky dark
• 3:37
  Speaker 2: matter particles people used to theorize about.
• 3:39
  Speaker 3: So the axion is what we call an ultra light particle.
• 3:42
  Speaker 2: Ultra light How light is ultra light?
• 3:44
  Speaker 3: Well, to give you a sense of scale, its mass
• 3:46
  Speaker 3: is so vanishingly small that it might be a trillionth
• 3:51
  Speaker 3: of a trillionth the mass of a single electron.
• 3:54
  Speaker 2: A trillionth of a trillion that's I mean, that's barely
• 3:56
  Speaker 2: even a thing exactly.
• 3:57
  Speaker 3: Because each individual axion carries almost zero mass. The only
• 4:01
  Speaker 3: way they could account for the immense gravitational weight of
• 4:04
  Speaker 3: dark matter in our galaxy is if there is an
• 4:06
  Speaker 3: unimaginably large number of them.
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  Speaker 2: Way a completely absurd amount, Right.
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  Speaker 3: We're talking about a density so high that they just
• 4:14
  Speaker 3: permeate every single inch of the universe around us.
• 4:16
  Speaker 2: Okay, let's unpack this. Yeah, because trying to visualize a
• 4:21
  Speaker 2: swarm of invisible, almost weightless particles making up a quarter
• 4:25
  Speaker 2: of the universe is honestly hurting my brain a bit.
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  Speaker 3: It's definitely not easy to picture.
• 4:29
  Speaker 2: So I want to picture this correctly. When scientists model axions,
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  Speaker 2: they don't treat them like a hail storm of tiny
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  Speaker 2: individual bullets, do they. They treat them as a classical field.
• 4:40
  Speaker 3: Right they do. Yeah, And it really comes down to
• 4:43
  Speaker 3: a fundamental principle of quantum mechanics called the Dobroglei.
• 4:46
  Speaker 2: Wavelength the de Brogli wavelength. Right.
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  Speaker 3: In quantum physics, every particle can also be described as
• 4:51
  Speaker 3: a wave, and the lighter the particle, the longer its
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  Speaker 3: wave stretches out.
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  Speaker 2: Okay, that makes sense. The lighter equals longer.
• 4:59
  Speaker 3: Exactly because because the axion is so incredibly light, it's
• 5:02
  Speaker 3: quantum wavelength is just huge compared to standard sub atomic particles.
• 5:07
  Speaker 2: So you have these massive, stretched out waves, and because
• 5:09
  Speaker 2: you need trillions upon trillions of them packed into the
• 5:12
  Speaker 2: exact same space just to make up a tiny bit
• 5:14
  Speaker 2: of gravity, they all sort of crowd together.
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  Speaker 3: And when they crowd together, those elongated quantum waves overlap,
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  Speaker 3: they sync.
• 5:22
  Speaker 2: Up, they sink up.
• 5:23
  Speaker 3: Yeah. Instead of acting like a bunch of erratic individual
• 5:26
  Speaker 3: particles bouncing around, they behave collectively, they just wash over
• 5:29
  Speaker 3: the Earth as a single macroscopic.
• 5:32
  Speaker 2: Wave, oscillating it as specific frequency.
• 5:34
  Speaker 3: Precisely, that smooth, continuous sloshing that is the classical field model.
• 5:40
  Speaker 2: I think I've got it. It's like the difference between
• 5:42
  Speaker 2: looking at dark matter as a massive invisible ocean current,
• 5:47
  Speaker 2: that macroscopic classical field versus you know, focusing on the
• 5:51
  Speaker 2: individual microscopic drops of water that make up the current.
• 5:54
  Speaker 3: That is a perfect way to look at it.
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  Speaker 2: So currently we're just constantly swimming in this smooth ocean
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  Speaker 2: current of dark matter.
• 6:00
  Speaker 3: Yeah, that ocean current analogy perfectly captures the classical view,
• 6:05
  Speaker 3: and it works flawlessly for predicting how galaxies form and
• 6:08
  Speaker 3: how gravity behaves on a large cosmological scale.
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  Speaker 2: Here's where it gets really interesting, though, because if axioans
• 6:16
  Speaker 2: are technically sub atomic particles, you know, these tiny drops
• 6:20
  Speaker 2: of water, shouldn't they behave by the bizarre rules of
• 6:23
  Speaker 2: quantum mechanics. When we look closely.
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  Speaker 3: Enough, you would think so.
• 6:26
  Speaker 2: Yes. If you zoom in on anything with a powerful
• 6:28
  Speaker 2: enough microscope, the smooth illusion usually breaks down, right and
• 6:31
  Speaker 2: you see the discrete quantum pieces.
• 6:34
  Speaker 3: And that logical leap is the exact foundation of the
• 6:37
  Speaker 3: current push to build highly sensitive dark matter detectors.
• 6:41
  Speaker 2: Okay, so that's what we're trying to do, right.
• 6:43
  Speaker 3: Physicists have developed these instruments called haloscopes taloscopes. Yeah, they
• 6:47
  Speaker 3: use incredibly powerful magnetic fields and superconducting quantum sensors. They
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  Speaker 3: are attempting to coax a single axion to interact with
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  Speaker 3: the magnetic field and basically canvert into a detectable microwave photon.
• 7:02
  Speaker 2: So we're trying to build machines that can detect the
• 7:05
  Speaker 2: absolute faintest whispers of energy, the absolute faintest. Yes, we
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  Speaker 2: basically want the machine to go click when a single
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  Speaker 2: drop of water from that dark matter ocean hits it.
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  Speaker 3: Exactly. The scientific community assumed that by utilizing detectors that
• 7:19
  Speaker 3: operate on strict quantum principles, we would naturally be able
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  Speaker 3: to detect the underline, discrete quantum nature of the dark
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  Speaker 3: matter itself.
• 7:27
  Speaker 2: We just expected it to happen, right.
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  Speaker 3: We anticipated seeing the erratic particle like behavior, those individual
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  Speaker 3: clicks of quantum interactions you just mentioned.
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  Speaker 2: And this is where a team of physicists Lion Tao
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  Speaker 2: Wang and his colleagues from the University of Chicago, Lawrence
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  Speaker 2: Berkeley National Lab, and UC Berkeley stepped in and realized
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  Speaker 2: a major piece of the puzzle was simply missing.
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  Speaker 3: A huge piece.
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  Speaker 2: Yeah, because we were using all this advanced quantum math
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  Speaker 2: to engineer the inner workings of the detectors, but researchers
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  Speaker 2: hadn't actually applied strict quantum mechanics to describe the dark
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  Speaker 2: matter itself at the exact moment it interacts with the machine.
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  Speaker 3: Which reveals a really fascinating blind spot in the theoretical framework.
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  Speaker 2: A huge blind spot.
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  Speaker 3: Yeah, the models dictating how the detector operates were entirely quantum,
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  Speaker 3: but the input in a dark matter expected to hit
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  Speaker 3: the detector was still largely being fed in as a
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  Speaker 3: smooth classical wave.
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  Speaker 2: Okay, I really have to push back on the logic
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  Speaker 2: of the scientific community here.
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  Speaker 3: Oh, fair enough, go ahead.
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  Speaker 2: Why would physicists spend decades at like millions of dollars
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  Speaker 2: building highly sensitive quantum heloscopes without first checking the fundamental
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  Speaker 2: math to see if the dark matter they are looking
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  Speaker 2: for actually acts like a quantum particle when it strikes
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  Speaker 2: the sensor. I know, I know. It feels like building
• 8:43
  Speaker 2: an ultra sensitive microphone to record a bat's echo location
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  Speaker 2: without I don't know, checking if bats actually make noise
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  Speaker 2: in that frequency.
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  Speaker 3: It really seems like a massive oversight when you frame
• 8:53
  Speaker 3: it that way, but it stems from how theoretical physics
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  Speaker 3: practically evolves. You mean, well, the classical field model that
• 9:01
  Speaker 3: smooth ocean current. It explained all the gravitational effects we
• 9:05
  Speaker 3: could observe perfectly.
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  Speaker 2: Okay, so it worked right.
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  Speaker 3: So when experimentalists began designing quantum level detectors, they relied
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  Speaker 3: on a standard assumption. It is incredibly common in physics
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  Speaker 3: to assume that if you push your magnification deep enough
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  Speaker 3: into the microscopic realm, the classical limits will naturally break down.
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  Speaker 2: And the quantum stuff will just sort of pop out exactly.
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  Speaker 3: They assumed the discrete quantum signatures would just emerge. They
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  Speaker 3: didn't rigorously calculate the dark matter's quantum state during detection
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  Speaker 3: because honestly, that assumption just felt mathematically safe.
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  Speaker 2: Safe, until Wang and his team decided it was time
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  Speaker 2: to stop assuming and actually run the numbers exactly.
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  Speaker 3: They wanted to see what a quantum axion would mathematically
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  Speaker 3: look like to a modern quantum detector.
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  Speaker 2: So what did they do.
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  Speaker 3: They built a brand new, entirely quantum mechanical framework from
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  Speaker 3: the ground up, modeling both the detector and the dark
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  Speaker 3: matter as interacting quantum entities.
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  Speaker 2: They put the whole system into the quantum math.
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  Speaker 3: Right. They set out to mathematically prove whether an experiment
• 10:10
  Speaker 3: could distinguish the hidden quantum states, those discrete particle like
• 10:14
  Speaker 3: clicks from the continuous, smooth, classical wave state we've always modeled.
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  Speaker 2: And the findings they publish, which are incredible by the way,
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  Speaker 2: they found that the intrinsically quantum effects of axions are
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  Speaker 2: completely fundamentally undetectable.
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  Speaker 3: Undetectable.
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  Speaker 2: Yes, when the detector looks at the dark matter, it
• 10:32
  Speaker 2: basically only sees the classical.
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  Speaker 3: Wave, right, The discrete quantum nature just vanishes.
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  Speaker 2: But why why does a fundamental particle just lose its
• 10:39
  Speaker 2: quantum identity like that?
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  Speaker 3: The disappearance of the quantum nature basically comes down to
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  Speaker 3: the relationship between the mean and the variance of the
• 10:46
  Speaker 3: signal mean invariance.
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  Speaker 2: Okay, let's break that down.
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  Speaker 3: So when a detector measures the axion field, it is
• 10:52
  Speaker 3: measuring the average strength of the wave over time. That
• 10:56
  Speaker 3: is the mean.
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  Speaker 2: Got it. The average is the mean.
• 10:58
  Speaker 3: But the quantum quarks, the individual particle interactions we are
• 11:01
  Speaker 3: actually looking for, they live in the variance.
• 11:05
  Speaker 2: The variants.
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  Speaker 3: Yeah, the tiny statistical fluctuations away from that average.
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  Speaker 2: Okay, so the fluctuations are the discrete.
• 11:11
  Speaker 3: Clicks precisely, And there are two major physical factors working
• 11:15
  Speaker 3: in tandem here to completely suppress those fluctuations.
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  Speaker 2: What's the first one?
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  Speaker 3: First, the sheer weakness of the interaction heavily penalizes our
• 11:24
  Speaker 3: ability to see anything other than the massive.
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  Speaker 2: Average because it's a ghost.
• 11:28
  Speaker 3: Right, Because the axion interacts so faintly with the magnetic
• 11:32
  Speaker 3: fields in our haloscopes to begin with, the overall signal
• 11:35
  Speaker 3: strength is incredibly low. It's super quiet, exactly so to
• 11:39
  Speaker 3: see tiny variances inside an already microscopic signal requires just
• 11:44
  Speaker 3: an impossible level of precision.
• 11:46
  Speaker 2: Wait, earlier we established that there are trillions upon trillions
• 11:49
  Speaker 2: of these axions permeating everything, Right, doesn't the sheer volume
• 11:53
  Speaker 2: of particles make up for the weak interaction, Like, if
• 11:56
  Speaker 2: enough of them are flowing through the detector, shouldn't the
• 11:59
  Speaker 2: sheer quantity amplify those little quantum fluctuations.
• 12:02
  Speaker 3: See, that is the intuitive assumption, but statistically the exact
• 12:06
  Speaker 3: opposite happens.
• 12:07
  Speaker 2: The opposite.
• 12:07
  Speaker 3: Yeah, the immense density of the axions is actually the
• 12:10
  Speaker 3: primary mechanism hiding their quantum nature.
• 12:13
  Speaker 2: You're kidding, No, It is an.
• 12:14
  Speaker 3: Extreme example of the central limit theorem in statistics.
• 12:18
  Speaker 2: The central limit theorem. Okay, let's try to visualize this.
• 12:22
  Speaker 2: Imagine you are standing in the middle of a massive stadium, Okay,
• 12:26
  Speaker 2: a stadium, and there are one hundred thousand people in
• 12:29
  Speaker 2: the stands, and they are all humming the exact same
• 12:33
  Speaker 2: continuous note.
• 12:34
  Speaker 3: Okay, so the humming represents the mean the macroscopic classical
• 12:39
  Speaker 3: dark matter wave rolling over the Earth.
• 12:41
  Speaker 2: Right now. In the quantum world, things are a little unpredictable.
• 12:45
  Speaker 2: So maybe one person over in section one oh four
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  Speaker 2: has their voice cracked for a split second. Okay, that
• 12:50
  Speaker 2: tiny vocal fluctuation, that little anomaly, That is your quantum variance.
• 12:54
  Speaker 2: That's the discrete particle click we want to hear.
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  Speaker 3: But here's the problem. If you are standing in the
• 12:59
  Speaker 3: center of the field holding a microphone, you aren't just
• 13:02
  Speaker 3: recording that one person in section one o four.
• 13:04
  Speaker 2: You're recording the other ninety nine hundred ninety nine people
• 13:09
  Speaker 2: constantly humming that perfect, overwhelming note exactly. The sheer volume
• 13:14
  Speaker 2: of the massive crowd completely drowns out the anomaly. The
• 13:17
  Speaker 2: massive number of axions hitting the detector means those tiny
• 13:21
  Speaker 2: quantum variances just average out into the smooth, continuous roar
• 13:25
  Speaker 2: of the classical wave.
• 13:26
  Speaker 3: It is physically impossible to hear the voice crack wow
• 13:29
  Speaker 3: because the detector is absorbing energy from so many overlapping
• 13:33
  Speaker 3: axion waves simultaneously. The quantum fluctuations just smooth themselves over.
• 13:38
  Speaker 2: They just blur together, right.
• 13:39
  Speaker 3: The mathematics of the wangpaper prove that these quantum signatures
• 13:43
  Speaker 3: would only manifest as extremely slight changes to what statisticians
• 13:46
  Speaker 3: call higher order statistics.
• 13:48
  Speaker 2: Higher order statistics, So we are talking about analyzing the
• 13:52
  Speaker 2: shape of the data curve itself.
• 13:54
  Speaker 3: Yes, you're looking at things like the skewness of the
• 13:56
  Speaker 3: signal or the variance of the variants. You are basically
• 13:59
  Speaker 3: trying to find correlations in the noise.
• 14:01
  Speaker 2: Of the data, which sounds impossible.
• 14:03
  Speaker 3: It essentially is because as the number of particles in
• 14:06
  Speaker 3: the field approaches the astronomical numbers required for dark matter,
• 14:10
  Speaker 3: the central limit theorem dictates that the variance grows much
• 14:14
  Speaker 3: much slower than.
• 14:15
  Speaker 2: The mean, So the signal just disappears.
• 14:18
  Speaker 3: The quantum signal essentially gets pushed to zero relative to
• 14:21
  Speaker 3: the classical wave.
• 14:22
  Speaker 2: It becomes a statistical whisper lost in a hurricane.
• 14:25
  Speaker 3: That's a great way to put it. And it leads
• 14:27
  Speaker 3: to the most staggering calculation in their entire paper. With that, well,
• 14:32
  Speaker 3: the researchers wanted to know the absolute limit. They assumed
• 14:35
  Speaker 3: an optimally designed, theoretically perfect experiment utilizing the absolute pinnacle
• 14:41
  Speaker 3: of quantum technology, running without any background noise whatsoever.
• 14:45
  Speaker 2: A perfect machine, and to find those higher order statistics,
• 14:49
  Speaker 2: you know, to hear that single voice crack in a
• 14:51
  Speaker 2: stadium of trillions, How long would this perfect machine need
• 14:54
  Speaker 2: to run?
• 14:55
  Speaker 3: The experiment would have to run for significantly longer than
• 14:57
  Speaker 3: the age of the universe.
• 14:59
  Speaker 2: Significantly longer than the thirteen point eight billion years our
• 15:02
  Speaker 2: universe has even existed, just to catch a single statistical
• 15:06
  Speaker 2: glimpse of a quantum axion doing something quantum that is,
• 15:11
  Speaker 2: I mean, that is the universe firmly closing a door.
• 15:13
  Speaker 2: It's a hard physical limit, it really is.
• 15:16
  Speaker 3: It forces us to confront a profound boundary on what
• 15:19
  Speaker 3: is observable in our reality. Yeah, the sheer density required
• 15:22
  Speaker 3: for the axion to be dark matter makes us underlying
• 15:25
  Speaker 3: quantum mechanics eternally inaccessible to us.
• 15:28
  Speaker 2: So what does this all mean? Because learning that an
• 15:31
  Speaker 2: experiment would take fourteen billion years sounds like a massive
• 15:35
  Speaker 2: crushing failure for physics. If the quantum effects are totally invisible,
• 15:39
  Speaker 2: doesn't that render all our highly sensitive quantum heloscopes and
• 15:42
  Speaker 2: sensors completely useless.
• 15:44
  Speaker 3: It's so crucial to make the distinction between the quantum
• 15:47
  Speaker 3: nature of the dark matter and the quantum sensitivity of the.
• 15:50
  Speaker 2: Detector, because they aren't the same thing.
• 15:52
  Speaker 3: Exactly, because the immediate reaction is often disappointment, like you said,
• 15:55
  Speaker 3: But the detectors we are building are not useless at all.
• 15:58
  Speaker 2: They aren't.
• 15:59
  Speaker 3: No. In fact, establishing this physical limit is a massive victory.
• 16:03
  Speaker 3: It clears a dense fog of uncertainty for experimental physicists.
• 16:08
  Speaker 2: Okay, how does hitting a fourteen billion year wall help
• 16:12
  Speaker 2: the people building the machines?
• 16:14
  Speaker 3: It resolves a massive amount of theoretical anxiety.
• 16:16
  Speaker 2: In the field, anxiety about what Well.
• 16:19
  Speaker 3: Returning to your ocean analogy, our quantum detectors are absolutely
• 16:22
  Speaker 3: phenomenal at feeling the push of the massive ocean current.
• 16:26
  Speaker 3: The high sensitivity is still required because the classical wave
• 16:29
  Speaker 3: itself interacts so weakly with standard matter. Oh, I see,
• 16:33
  Speaker 3: we need quantum level precision just to detect the macroscopic wave.
• 16:37
  Speaker 2: Ah, so we need the ultrasensitive quantum microphone just to
• 16:41
  Speaker 2: hear the crowd humming in the first place.
• 16:43
  Speaker 3: Yes, what the study definitively proves is simply that we
• 16:46
  Speaker 3: don't need to worry about trying to calibrate our machines
• 16:49
  Speaker 3: to isolate the individual drops.
• 16:50
  Speaker 2: Of water, because we literally can't.
• 16:52
  Speaker 3: Right. Prior to this mathematical proof, physicists were actively debating
• 16:56
  Speaker 3: whether intrinsic quantum fluctuations in the dark matter field might
• 17:00
  Speaker 3: be skewing our data or creating strange interferences that were
• 17:04
  Speaker 3: causing us to miss the signal entirely.
• 17:07
  Speaker 2: So people were actually stressing out that the quantum quirks
• 17:10
  Speaker 2: of the axions were throwing off the calibration of the.
• 17:13
  Speaker 3: Traps exactly, and Wang and his team rigorously demonstrated that
• 17:18
  Speaker 3: we can completely ignore those quantum.
• 17:20
  Speaker 2: Effects because they average out to zero.
• 17:22
  Speaker 3: Because they average out to zero, they will not interfere
• 17:26
  Speaker 3: with the classical detection. This validates our historical models so easy.
• 17:31
  Speaker 3: It proves that treating axion dark matter as a classical
• 17:34
  Speaker 3: macroscopic wavefield works flawlessly on an experimental level, even when
• 17:39
  Speaker 3: using quantum instruments. We can trust the classical models when
• 17:43
  Speaker 3: we are hunting for the dark matter signal.
• 17:45
  Speaker 2: So it's basically the universe giving us permission to simplify
• 17:48
  Speaker 2: our approach pretty much. We don't have to account for
• 17:51
  Speaker 2: the unpredictable discrete quantum behavior on the dark matter side
• 17:55
  Speaker 2: because the universe naturally smooths it out for us. We
• 17:58
  Speaker 2: just focus our quantum detectors on catching the big wave.
• 18:01
  Speaker 3: It's correctly what signal profile we are looking for.
• 18:07
  Speaker 2: Now. That is a huge relief, it is.
• 18:09
  Speaker 3: And what makes this realization even more impactful is that
• 18:12
  Speaker 3: this averaging out phenomenon isn't restricted to just axions.
• 18:15
  Speaker 2: Wait, this applies to other areas of physics.
• 18:18
  Speaker 3: It does. The exact same quantum hiding logic applies to
• 18:21
  Speaker 3: the detection of gravitational waves.
• 18:23
  Speaker 2: Gravitational waves. Oh, that makes perfect sense, because we detect
• 18:27
  Speaker 2: gravitational waves using massive interferometers like Lego.
• 18:30
  Speaker 3: Right.
• 18:31
  Speaker 2: And theoretically gravity is composed of subatomic quantum particles called gravitons.
• 18:36
  Speaker 3: Exactly, But a gravitational wave generated by say two black
• 18:41
  Speaker 3: holes colliding it contains such an astronomically immense number of
• 18:46
  Speaker 3: gravitons that their individual quantum quirks average.
• 18:49
  Speaker 2: Out entirely, just like the axions.
• 18:51
  Speaker 3: Just like the axiom field, the variance vanishes, and our
• 18:55
  Speaker 3: detectors only observe the smooth classical ripple in space time
• 19:00
  Speaker 3: virtual limit theorem and forces classical physics on any ultra light,
• 19:03
  Speaker 3: highly abundant particle field.
• 19:05
  Speaker 2: The bigger the crowd, the smooth than noise.
• 19:07
  Speaker 3: I perfectly said, and this mathematical framework provides a real
• 19:10
  Speaker 3: launch pad for future engineering.
• 19:12
  Speaker 2: How so well.
• 19:13
  Speaker 3: The researchers noted that their ongoing work involves developing a
• 19:15
  Speaker 3: complete end to end quantum mechanical description of the detection process.
• 19:20
  Speaker 2: But I thought we just said we can't see the
• 19:21
  Speaker 2: quantum stuff.
• 19:22
  Speaker 3: We can't. They aren't doing this to look for the
• 19:25
  Speaker 3: impossible quantum quirks of the axion. They are using that
• 19:29
  Speaker 3: deep mathematical understanding to search for entirely new quantum techniques
• 19:34
  Speaker 3: to build better traps for the classical wave.
• 19:36
  Speaker 2: Oh wow.
• 19:37
  Speaker 3: They are utilizing the hard limits of what we can't
• 19:39
  Speaker 3: see to optimize how we search for what we can see.
• 19:42
  Speaker 2: A closed door just forces you to engineer a better window.
• 19:45
  Speaker 3: I love that exactly.
• 19:47
  Speaker 2: So let's recap the journey here. We started with the
• 19:50
  Speaker 2: universe's most delusive ghost, dark matter right. We zoomed in,
• 19:55
  Speaker 2: assuming that our incredible new quantum technology would reveal the
• 19:59
  Speaker 2: microscope discrete quantum secrets of the axion, But instead we
• 20:04
  Speaker 2: found that it's overwhelming abundance moves out all its quantum fluctuations.
• 20:08
  Speaker 3: It's all about the averages.
• 20:09
  Speaker 2: The central limit theorem basically hides its discrete nature behind
• 20:13
  Speaker 2: the roar of the crowd, leaving us with a continuous
• 20:16
  Speaker 2: classical wave.
• 20:17
  Speaker 3: A wave we are now better equipped to find, precisely
• 20:20
  Speaker 3: because we are no longer distracted by the search for
• 20:22
  Speaker 3: its quantum.
• 20:22
  Speaker 2: Ripples, which is just so fascinating, and it leaves me
• 20:25
  Speaker 2: with this lingering thought. You know what's that? Well, we
• 20:28
  Speaker 2: are so used to thinking of the quantum realm as
• 20:30
  Speaker 2: the true fundamental base.
• 20:33
  Speaker 3: Of reality, right the bottom level of everything.
• 20:35
  Speaker 2: Exactly. We assume that if you strip away the illusion
• 20:38
  Speaker 2: of our macroscopic world, the microscopic truth is always discrete
• 20:42
  Speaker 2: in quantum. But if the most abundant form of matter
• 20:46
  Speaker 2: in the universe hides its fundamental quantum nature simply because
• 20:50
  Speaker 2: there's too much of it crowding together, it makes you wonder,
• 20:54
  Speaker 2: wonder what what other mind bending quantum realities are happening?
• 20:58
  Speaker 2: All around you right now, perfectly hidden in plain sight,
• 21:01
  Speaker 2: just because the universe is too noisy for you to
• 21:03
  Speaker 2: hear them.
• 21:04
  Speaker 3: That's a profound point. We navigate a macroscopic reality entirely
• 21:08
  Speaker 3: smoothed over by averages. The discrete truths are just buried
• 21:12
  Speaker 3: under the weight of sheer numbers.
• 21:13
  Speaker 2: Exactly so you know, the next time you step outside
• 21:16
  Speaker 2: and look up at that vast night sky and you
• 21:19
  Speaker 2: realize you're only seeing a tiny fraction of what is
• 21:21
  Speaker 2: out there, remember that even the invisible things have secrets
• 21:25
  Speaker 2: they will never tell they really do. The universe is loud,
• 21:28
  Speaker 2: it is crowded, and sometimes the most profound mysteries are
• 21:31
  Speaker 2: the ones that simply refuses to let us hear