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