Latest / The Quark Side - Quantum Physics Podcast / Quantum Gravity: Could Spacetime Emerge From Information?

Transcript

Quantum Gravity: Could Spacetime Emerge From Information? · The Quark Side - Quantum Physics Podcast

• 0:01
  Speaker 1: Welcome to the Quarkside Quantum Physics Podcast, an exploration of
• 0:05
  Speaker 1: the fundamental structure of reality, where quantum laws govern matter, energy,
• 0:11
  Speaker 1: and information. Here, uncertainty is a feature, not a flaw,
• 0:16
  Speaker 1: and understanding begins at the smallest scales.
• 0:27
  Speaker 2: So, what if I told you that the gravity holding
• 0:32
  Speaker 2: you in your chair right now.
• 0:34
  Speaker 3: Oh, boy.
• 0:35
  Speaker 2: No, seriously, think about it. The force keeping the Earth
• 0:37
  Speaker 2: orbiting the sun and like the very thing that gives
• 0:41
  Speaker 2: you weight. What if it isn't a real physical force
• 0:44
  Speaker 2: at all? Right. What if it's actually just a byproduct,
• 0:48
  Speaker 2: like a cosmic illusion or I don't know, maybe even
• 0:51
  Speaker 2: a glitch in the universe's fundamental data?
• 0:54
  Speaker 3: I mean, it sounds completely absurd on its face because
• 0:57
  Speaker 3: we feel gravity in every single step we take. Yeah, exactly.
• 1:01
  Speaker 3: But if we connect this to the bigger picture of
• 1:03
  Speaker 3: modern physics, the idea that gravity is essentially an illusion
• 1:08
  Speaker 3: might actually be the only way to solve the absolute
• 1:11
  Speaker 3: greatest mystery in science right now. Okay.
• 1:13
  Speaker 2: Let's unpack this.
• 1:14
  Speaker 3: Yeah.
• 1:14
  Speaker 2: Because to really understand why scientists are even questioning the
• 1:18
  Speaker 2: reality of gravity, we kind of have to look at
• 1:21
  Speaker 2: the absolute mess we're currently dealing with in physics.
• 1:24
  Speaker 3: It is a mess. It is.
• 1:26
  Speaker 2: For over a century, we've essentially been running the universe
• 1:29
  Speaker 2: on two completely different operating systems that they absolutely refuse
• 1:34
  Speaker 2: to talk to each other.
• 1:34
  Speaker 3: Yeah, it's the ultimate cosmic clash. On one side, you
• 1:38
  Speaker 3: have Albert Einstein's general relativity, right? And this is our
• 1:42
  Speaker 3: macroscopic operating system.
• 1:43
  Speaker 2: The big stuff.
• 1:44
  Speaker 3: Right, the big stuff. It describes stars, galaxies, black holes, and,
• 1:48
  Speaker 3: of course, gravity. And Einstein taught us that gravity isn't
• 1:51
  Speaker 3: some invisible tether just pulling planets together. It's the actual...
• 1:55
  Speaker 3: Physical warping and curving of the fabric of space and time.
• 1:58
  Speaker 2: Like heavy things bend the fabric and other things roll
• 2:01
  Speaker 2: down those curves.
• 2:02
  Speaker 3: Exactly. And that framework is just, it's gorgeous. It's smooth.
• 2:06
  Speaker 3: It's elegant. It's incredibly predictable.
• 2:09
  Speaker 2: But then you zoom in.
• 2:10
  Speaker 3: Right.
• 2:11
  Speaker 2: You look at the microscopic world of atoms and electrons
• 2:13
  Speaker 2: and quarks and Einstein's smooth, predictable math just completely falls apart.
• 2:18
  Speaker 3: Completely.
• 2:19
  Speaker 2: Because down there, the second operating system takes over, which
• 2:22
  Speaker 2: is quantum mechanics. And quantum mechanics is... Well, it's jittery.
• 2:27
  Speaker 3: Yeah, it operates in these discrete, completely unpredictable leaps. It's chaotic.
• 2:31
  Speaker 3: It's governed entirely by probability.
• 2:33
  Speaker 2: But the problem, the really big problem, is that the
• 2:37
  Speaker 2: universe isn't actually divided by some magical wall, you know?
• 2:40
  Speaker 3: No, exactly. The big stuff is quite literally made out
• 2:43
  Speaker 3: of the microscopic stuff.
• 2:44
  Speaker 2: Right.
• 2:45
  Speaker 3: So there has to be a way that the jumpy,
• 2:47
  Speaker 3: chaotic quantum world somehow creates the smooth, curved world of gravity.
• 2:52
  Speaker 3: But every single time physicists try to combine the math
• 2:55
  Speaker 3: of these two theories, they just get infinite, completely nonsensical answers.
• 2:59
  Speaker 2: Right. Uniting them into one single theory of quantum gravity
• 3:02
  Speaker 2: is like the Holy Grail. Yeah.
• 3:04
  Speaker 3: Which brings us to a really monumental shift in how
• 3:06
  Speaker 3: we're approaching this whole problem. Instead of trying to force
• 3:10
  Speaker 3: these two wildly different rule books to merge, theoretical physicists
• 3:14
  Speaker 3: are now exploring this staggering idea. What if they're actually
• 3:19
  Speaker 3: both just speaking the exact same language?
• 3:21
  Speaker 2: The language of quantum information. Yes.
• 3:24
  Speaker 3: That's the breakthrough here. We're looking at a genuinely novel
• 3:28
  Speaker 3: mathematical proof that suggests the gravity we experience is really
• 3:31
  Speaker 3: just a macro-level expression of how microscopic quantum information is structured.
• 3:38
  Speaker 2: Space, time, gravity, they aren't the bottom level of reality.
• 3:42
  Speaker 3: They emerge from something deeper.
• 3:44
  Speaker 2: Right. Emergent is a word that gets thrown around a
• 3:47
  Speaker 2: lot in physics, and I really want to make sure
• 3:49
  Speaker 2: we nail down what that actually means before we get
• 3:51
  Speaker 2: into the heavy quantum math.
• 3:53
  Speaker 3: Good idea.
• 3:54
  Speaker 2: Let's use a classic analogy. Think about a balloon filled
• 3:58
  Speaker 2: with air. Now, when you press against that balloon, it
• 4:00
  Speaker 2: feels firm, right? It has pressure. And if you hold it,
• 4:04
  Speaker 2: it has a specific temperature.
• 4:05
  Speaker 3: Yeah. But if you were to zoom in on that
• 4:08
  Speaker 3: balloon with like a super powerful microscope, you wouldn't find
• 4:11
  Speaker 3: a single particle of pressure. Right. You wouldn't find a
• 4:15
  Speaker 3: molecule of temperature. Those concepts simply do not exist at
• 4:18
  Speaker 3: the fundamental microscopic level.
• 4:21
  Speaker 2: Right. All you would see are billions of individual gas
• 4:24
  Speaker 2: molecules just rocketing around in total chaos, smashing into each other,
• 4:27
  Speaker 2: bouncing off the rubber walls.
• 4:29
  Speaker 3: Exactly. The pressure and the heat you feel are just
• 4:32
  Speaker 3: the collective crowd effect of all those invisible microscopic collisions.
• 4:37
  Speaker 3: You don't measure the individual molecules. Your hand just feels
• 4:40
  Speaker 3: the macroscopic average.
• 4:42
  Speaker 2: Okay, so what's really fascinating here is that physicists have
• 4:45
  Speaker 2: basically suspected for decades that gravity operates the exact same way.
• 4:49
  Speaker 2: Like this idea didn't just appear out of thin air overnight.
• 4:51
  Speaker 3: No, not at all. The critical seed for this was
• 4:54
  Speaker 3: actually planted way back in 1995 by a theoretical physicist
• 4:58
  Speaker 3: named Ted Jacobson.
• 4:59
  Speaker 2: And Jacobson did something that kind of shook the foundations
• 5:02
  Speaker 2: of relativity, didn't he?
• 5:03
  Speaker 3: He really did. He looked at classical thermodynamics, so the
• 5:07
  Speaker 3: physics of heat, entropy, energy, And he managed to mathematically
• 5:11
  Speaker 3: massage those concepts until Einstein's equations of gravity literally popped out.
• 5:16
  Speaker 2: Wow.
• 5:17
  Speaker 1: Yeah.
• 5:17
  Speaker 3: He essentially showed that the geometry of spacetime behaves exactly
• 5:21
  Speaker 3: like a thermodynamic system. It was this massive clue that
• 5:24
  Speaker 3: gravity isn't a fundamental built-in force, but an emergent crowd
• 5:28
  Speaker 3: effect of deeper hidden variables. Okay, wait.
• 5:31
  Speaker 2: I need to push back on this for just a
• 5:33
  Speaker 2: second because the balloon analogy makes perfect sense for heat.
• 5:36
  Speaker 2: I can picture molecules bouncing off rubber to create pressure. Sure.
• 5:40
  Speaker 2: But gravity isn't trapped in a rubber balloon. It's pulling,
• 5:43
  Speaker 2: I don't know, a bowling ball and a feather down
• 5:45
  Speaker 2: at the exact same rate in a vacuum. So if
• 5:48
  Speaker 2: gravity is just a crowd effect, like an illusion of
• 5:50
  Speaker 2: something else, how does it know how to uniformly pull
• 5:53
  Speaker 2: on physical mass? Like what are the molecules bouncing around
• 5:57
  Speaker 2: to create the gravity?
• 5:59
  Speaker 3: That is the million dollar question. And for a really
• 6:01
  Speaker 3: long time, Jacobson's work couldn't actually answer it. Right. Because
• 6:05
  Speaker 3: his 1995 paper, while brilliant, was entirely based on classical physics.
• 6:10
  Speaker 3: It was macroscopic. He basically proved that gravity behaves like heat,
• 6:15
  Speaker 3: but he didn't have the mathematical microscope to identify what
• 6:18
  Speaker 3: the actual fire was, so to speak.
• 6:21
  Speaker 2: It was all heuristic, right? Yeah.
• 6:22
  Speaker 3: Suggestive, intuitive arguments, but lacking a fully rigorous underlying microscopic framework.
• 6:29
  Speaker 2: So it's kind of like knowing a car is moving
• 6:30
  Speaker 2: forward and knowing the wheels are turning, but having absolutely
• 6:33
  Speaker 2: no idea what an engine is.
• 6:35
  Speaker 3: Precisely. To find the engine, we needed to upgrade the math.
• 6:39
  Speaker 3: We couldn't rely on classical thermodynamics anymore. We had to
• 6:42
  Speaker 3: go all the way down to the foundational layer, which
• 6:44
  Speaker 3: is quantum mechanics.
• 6:45
  Speaker 2: And that is exactly what a team of theoretical physicists,
• 6:49
  Speaker 2: so we're talking about Albert Mutsch from the University of
• 6:51
  Speaker 2: Sharjah and Philip Dorough from Leipzig University, that's what they've
• 6:55
  Speaker 2: just done in this newly published breakthrough.
• 6:57
  Speaker 3: Exactly.
• 6:58
  Speaker 2: They reconstructed the entire derivation of general relativity, but they
• 7:02
  Speaker 2: totally threw out the old classical thermodynamics, and they replaced
• 7:06
  Speaker 2: it with a highly sophisticated tool from quantum information theory. Right.
• 7:11
  Speaker 3: They used this concept known as quantum relative entropy.
• 7:15
  Speaker 2: Okay, quantum relative entropy. I mean, that sounds incredibly intimidating,
• 7:19
  Speaker 2: but I know we can break this down for you.
• 7:21
  Speaker 2: Let's start with just regular entropy, because usually we think
• 7:24
  Speaker 2: of entropy as like disorder or messiness in a system.
• 7:28
  Speaker 3: Right, but in physics, it's often way more accurate to
• 7:31
  Speaker 3: think of entropy as a measure of hidden information. Okay.
• 7:35
  Speaker 3: It's essentially the number of ways you can rearrange the
• 7:37
  Speaker 3: microscopic parts of a system without actually changing its macroscopic appearance.
• 7:42
  Speaker 3: But quantum relative entropy is a slightly different beast.
• 7:45
  Speaker 2: How so?
• 7:46
  Speaker 3: Well, it's a very precise mathematical tool used to measure
• 7:49
  Speaker 3: how distinguishable two different quantum states are from one another.
• 7:53
  Speaker 2: Distinguishability. Okay, let's visualize this. Imagine you're looking out at
• 7:57
  Speaker 2: the ocean. Even on the calmest, like most completely windless day,
• 8:02
  Speaker 2: the surface of the sea is never flawlessly flat.
• 8:05
  Speaker 3: No, never.
• 8:06
  Speaker 2: There's always this tiny chaotic rippling.
• 8:09
  Speaker 3: And that chaotic rippling is actually the perfect way to
• 8:11
  Speaker 3: picture the quantum vacuum. Because empty space is never truly empty.
• 8:16
  Speaker 3: It is constantly boiling with these tiny background quantum fluctuations.
• 8:21
  Speaker 3: It's just a baseline level of noise.
• 8:24
  Speaker 2: Okay, so we have our baseline noise, right? The ripples. Now,
• 8:27
  Speaker 2: imagine a distinct, really powerful wave suddenly passing across that
• 8:32
  Speaker 2: rippling surface. That wave is a new quantum state.
• 8:36
  Speaker 3: Exactly.
• 8:36
  Speaker 2: It's an injection of specific information. So in this analogy,
• 8:41
  Speaker 2: relative entropy is simply the mathematical measure of how easily
• 8:45
  Speaker 2: you can tell that specific wave apart from the chaotic
• 8:48
  Speaker 2: background ripples. Like, how clearly does the wave's information stand
• 8:52
  Speaker 2: out from the noise?
• 8:53
  Speaker 3: Right. It quantifies the exact difference in information. And by
• 8:56
  Speaker 3: swapping out those fuzzy classical concepts of heat and pressure
• 9:00
  Speaker 3: for this incredibly sharp, precise quantum tool, much Doro and
• 9:05
  Speaker 3: their team found a way to bridge the gap.
• 9:07
  Speaker 2: They connected the dots.
• 9:08
  Speaker 3: They figured out how to connect the microscopic ripples of
• 9:11
  Speaker 3: quantum data directly to the massive space bending gravity of Einstein.
• 9:17
  Speaker 2: But to actually do the math, they couldn't just drop
• 9:20
  Speaker 2: this tool into the middle of empty space, right? If
• 9:23
  Speaker 2: you really want to measure how information behaves, you have
• 9:26
  Speaker 2: to push it to a limit.
• 9:27
  Speaker 3: Yes.
• 9:28
  Speaker 2: You have to find a place where information behaves really strangely.
• 9:31
  Speaker 3: You have to look at a horizon.
• 9:33
  Speaker 2: And just to clarify for everyone, we aren't talking about
• 9:35
  Speaker 2: watching a sunset over the ocean here. In relativity, what
• 9:39
  Speaker 2: exactly is a horizon?
• 9:42
  Speaker 3: Basically, a horizon is a boundary in the fabric of spacetime.
• 9:46
  Speaker 3: It's a threshold beyond which no information can be retrieved.
• 9:49
  Speaker 2: Like a black hole.
• 9:50
  Speaker 3: Exactly. Exactly. The most famous example is the event horizon
• 9:53
  Speaker 3: of a black hole. And once anything, even a beam
• 9:57
  Speaker 3: of light, crosses that boundary, it is permanently disconnected. from
• 10:00
  Speaker 3: our observable universe.
• 10:02
  Speaker 2: Right.
• 10:02
  Speaker 3: But you can also have horizons in completely empty space,
• 10:06
  Speaker 3: purely based on how an observer is accelerating. It's essentially
• 10:10
  Speaker 3: just a cosmic curtain.
• 10:11
  Speaker 2: Okay, so we have this cosmic curtain. How does measuring
• 10:15
  Speaker 2: quantum relative entropy, so our waves standing out from the ripples,
• 10:20
  Speaker 2: at this curtain actually lead us to gravity? Because this
• 10:23
  Speaker 2: is the part that usually just gets glossed over as,
• 10:25
  Speaker 2: you know, the math works out like magic.
• 10:27
  Speaker 3: Right, right.
• 10:28
  Speaker 2: But I really want to understand the mechanism here. How
• 10:30
  Speaker 2: do we get from raw information to physical curvature?
• 10:35
  Speaker 3: Okay, so to get there, we have to build a
• 10:37
  Speaker 3: logical bridge, step by step.
• 10:38
  Speaker 2: Okay.
• 10:39
  Speaker 3: First, the researchers evaluated their quantum relative entropy equation right
• 10:43
  Speaker 3: at that horizon boundary. And their math proved something honestly staggering.
• 10:48
  Speaker 3: What's that? The quantum relative entropy at the horizon is
• 10:52
  Speaker 3: mathematically equal to the physical energy flowing across it.
• 10:56
  Speaker 2: Wait, pause. The amount of information, like how easily we
• 10:59
  Speaker 2: can distinguish our quantum wave, is perfectly equal to the
• 11:02
  Speaker 2: physical energy crossing the boundary.
• 11:03
  Speaker 3: Yes. They're inextricably linked. Information equates to energy. Wow.
• 11:09
  Speaker 2: Okay.
• 11:10
  Speaker 3: That is step one. Now, for step two, we have
• 11:13
  Speaker 3: to bring in two absolute titans of physics, Jacob Bekenstein
• 11:18
  Speaker 3: and Stephen Hawking.
• 11:19
  Speaker 2: Oh, the heavy hitters of black hole physics.
• 11:22
  Speaker 3: Exactly. Decades ago, Bekenstein and Hawking made this massive discovery
• 11:27
  Speaker 3: about horizons. They proved mathematically that the entropy of a
• 11:31
  Speaker 3: black hole, so its total information capacity, is directly proportional
• 11:36
  Speaker 3: to the physical surface area of its horizon.
• 11:39
  Speaker 2: Oh.
• 11:39
  Speaker 3: So the physical size of the horizon is essentially its
• 11:43
  Speaker 3: hard drive space.
• 11:45
  Speaker 2: Oh, that is a phenomenal way to phrase it.
• 11:47
  Speaker 3: Yes.
• 11:48
  Speaker 2: Yes.
• 11:48
  Speaker 3: The physical area dictates the information limit.
• 11:51
  Speaker 2: Okay.
• 11:52
  Speaker 3: So let's connect the dots here. The new research proves
• 11:55
  Speaker 3: that when energy flows across a horizon, it actually changes
• 11:58
  Speaker 3: the quantum relative entropy. It changes the information state.
• 12:02
  Speaker 2: And because of Beckensine and Hawking, if the information state changes,
• 12:06
  Speaker 2: the actual physical surface area of the horizon must change
• 12:10
  Speaker 2: to accommodate it.
• 12:11
  Speaker 3: Exactly. The boundary has to physically expand or contract. The
• 12:15
  Speaker 3: geometry of space itself has to literally shift. And what
• 12:19
  Speaker 3: do we call the shifting, bending, and stretching of the
• 12:21
  Speaker 3: geometry of space?
• 12:23
  Speaker 2: Space-time curvature.
• 12:25
  Speaker 3: Gravity.
• 12:25
  Speaker 2: Gravity.
• 12:26
  Speaker 3: There is your mechanism. By combining the quantum relative entropy
• 12:30
  Speaker 3: equation with the Bekenstein-Hawking area law, the math literally demands
• 12:34
  Speaker 3: that space must curve. Out pops Einstein's theory of general relativity.
• 12:39
  Speaker 2: That is wild.
• 12:41
  Speaker 3: Right. Not as a fundamental assumption, but as a mandatory
• 12:44
  Speaker 3: consequence of quantum information changing at a boundary.
• 12:48
  Speaker 2: Here's where it gets really interesting to me, because when
• 12:50
  Speaker 2: you map it out mechanically like that, it completely shatters
• 12:53
  Speaker 2: how I view the physical world. The heavy pulling sensation
• 12:58
  Speaker 2: of gravity, it isn't a magnet.
• 13:00
  Speaker 3: No.
• 13:00
  Speaker 2: It's literally just the fabric of space adjusting its shape
• 13:03
  Speaker 2: to accommodate the movement of quantum data.
• 13:06
  Speaker 3: Dr. Albert Mutch actually offered a really beautiful analogy to
• 13:09
  Speaker 3: help conceptualize this new hierarchy. He suggested imagining a guitar string.
• 13:15
  Speaker 2: Oh, I love this one.
• 13:17
  Speaker 1: Yeah.
• 13:17
  Speaker 2: In his analogy, the microscopic quantum matter in the universe,
• 13:21
  Speaker 2: the data, is the pluck. And the fabric of space-time
• 13:24
  Speaker 2: itself is the string. And when you pluck that string,
• 13:27
  Speaker 2: it vibrates and produces this beautiful, resonating musical note.
• 13:31
  Speaker 3: Right.
• 13:32
  Speaker 2: And that note is Einstein's equations. That note is gravity.
• 13:36
  Speaker 3: The physical gravity that keeps the planets in orbit is
• 13:38
  Speaker 3: really just the music produced by quantum information interacting with
• 13:42
  Speaker 3: the geometry of space. It just upends everything. because for
• 13:46
  Speaker 3: a century we thought gravity was the instrument.
• 13:49
  Speaker 2: And this proof suggests gravity is just the sound the
• 13:51
  Speaker 2: instrument makes.
• 13:52
  Speaker 3: Exactly.
• 13:54
  Speaker 2: But I imagine physicists aren't just taking this on faith,
• 13:57
  Speaker 2: because as you mentioned, scientists have known about Bekenstein and
• 14:00
  Speaker 2: Hawking for decades, right? The idea that black holes tie
• 14:03
  Speaker 2: information and gravity together, that isn't entirely new. So why
• 14:07
  Speaker 2: is this specific paper moving the needle so much? Like,
• 14:10
  Speaker 2: what makes this proof different from the intuition we already
• 14:14
  Speaker 2: had back in the 90s?
• 14:15
  Speaker 3: It all comes down to mathematical rigor. Before this, the
• 14:19
  Speaker 3: relationship between thermodynamics and gravity was really built on physical intuition.
• 14:24
  Speaker 2: Just a strong hunch.
• 14:25
  Speaker 3: Exactly. It was like knowing someone committed a crime because
• 14:28
  Speaker 3: they had a really strong motive, but lacking any of
• 14:30
  Speaker 3: the forensic evidence to actually convict them. The earlier arguments
• 14:34
  Speaker 3: were heuristic.
• 14:36
  Speaker 2: And this new paper is like the fingerprint on the vault.
• 14:39
  Speaker 3: It is. Because this derivation doesn't rely on those fuzzy
• 14:42
  Speaker 3: analogies about heat and pressure. It uses strictly defined, quantifiable
• 14:47
  Speaker 3: quantum mechanics. It takes a measurable concept, quantum relative entropy,
• 14:52
  Speaker 3: and mechanically fastens it to the geometry of space. It
• 14:56
  Speaker 3: bridges the microscopic and the macroscopic with just cold hard math.
• 15:00
  Speaker 3: It's a massive, massive step toward formally defining quantum gravity.
• 15:05
  Speaker 2: Okay, so what does this all mean for the rest
• 15:08
  Speaker 2: of us? I have to admit, my mind is completely
• 15:10
  Speaker 2: blown on a cosmic scale, but As a practical matter,
• 15:13
  Speaker 2: does this change anything tomorrow? Like if you're listening to
• 15:16
  Speaker 2: this while doing the dishes or walking the dog, does
• 15:19
  Speaker 2: knowing that gravity is a quantum illusion actually impact your
• 15:22
  Speaker 2: daily life?
• 15:22
  Speaker 3: I mean, in the immediate short term, no. This is
• 15:26
  Speaker 3: pure theoretical physics. You aren't going to buy a hoverboard
• 15:29
  Speaker 3: powered by quantum relative entropy next week.
• 15:31
  Speaker 2: Damn.
• 15:32
  Speaker 3: I know, right? But this raises a really important point
• 15:35
  Speaker 3: about how foundational science actually works. Because changing our understanding
• 15:39
  Speaker 3: of the very bottom layer of reality always has these enormous,
• 15:44
  Speaker 3: completely unpredictable consequences.
• 15:46
  Speaker 2: Can you give an example of how that trajectory usually
• 15:49
  Speaker 2: plays out?
• 15:50
  Speaker 3: Sure. Just look at Einstein's general relativity itself. When he
• 15:53
  Speaker 3: published it back in 1915, it was viewed purely as
• 15:57
  Speaker 3: this esoteric mathematical framework to understand the cosmos.
• 16:01
  Speaker 2: Right. Just chalkboard math.
• 16:03
  Speaker 3: Exactly. It's beautiful, but it had absolutely zero practical application
• 16:07
  Speaker 3: for the average person. But today, The global positioning system,
• 16:11
  Speaker 3: the GPS on your phone, relies entirely on general relativity.
• 16:16
  Speaker 2: Wait, really?
• 16:18
  Speaker 3: Well, because gravity warps time as well as space.
• 16:21
  Speaker 2: Oh, right.
• 16:22
  Speaker 3: So the clocks on the GPS satellites up in orbit
• 16:24
  Speaker 3: actually run at a slightly different speed than the clocks
• 16:27
  Speaker 3: down here on Earth because they're further away from the
• 16:29
  Speaker 3: planet's gravitational mass.
• 16:31
  Speaker 2: That is so weird.
• 16:33
  Speaker 3: It is. And if our satellites didn't use Einstein's equations
• 16:36
  Speaker 3: to constantly correct for that time dilation... Your phone's GPS
• 16:40
  Speaker 3: would literally drift by miles every single day. It would
• 16:43
  Speaker 3: be utterly useless.
• 16:45
  Speaker 2: So the deeply abstract math from a century ago is
• 16:47
  Speaker 2: the literal reason I can navigate a new city today.
• 16:50
  Speaker 3: Foundation science always pays off. And there's actually another really
• 16:56
  Speaker 3: incredible layer to this specific breakthrough.
• 16:58
  Speaker 2: What's that?
• 17:00
  Speaker 3: The mathematical language Mutch and Derauer are using to decode
• 17:02
  Speaker 3: the universe, so quantum information, is not just abstract theory.
• 17:08
  Speaker 3: It is the exact same framework driving the current real-world
• 17:11
  Speaker 3: revolution in quantum computing.
• 17:13
  Speaker 2: Oh, wow. So the concept of distinguishability, the qubits, the entanglement...
• 17:18
  Speaker 2: It's all.
• 17:19
  Speaker 3: The exact same math. The formulas they're using to figure
• 17:22
  Speaker 3: out the fabric of a black hole's horizon are mathematically
• 17:25
  Speaker 3: related to the formulas being used right now to build
• 17:28
  Speaker 3: the next generation of supercomputers.
• 17:30
  Speaker 2: That's amazing.
• 17:31
  Speaker 3: The more deeply we understand how quantum information operates, whether
• 17:34
  Speaker 3: it's way out in deep space or just inside a
• 17:37
  Speaker 3: silicon chip, the more mastery we gain over the physical world.
• 17:41
  Speaker 2: And the research definitely doesn't stop with this single proof,
• 17:44
  Speaker 2: does it? Now that they have this engine built, where
• 17:46
  Speaker 2: are they taking it next?
• 17:48
  Speaker 3: They want to push it to the absolute breaking point.
• 17:50
  Speaker 2: Naturally.
• 17:51
  Speaker 3: This initial proof used very specific conditions and assumptions just
• 17:55
  Speaker 3: to see if the math would even work. But now
• 17:57
  Speaker 3: they're looking at more general, complex scenarios. They want to
• 18:00
  Speaker 3: test different forms of quantum matter. Okay. They want to
• 18:04
  Speaker 3: apply this to light-like surfaces, which are super crucial to
• 18:08
  Speaker 3: understanding the really chaotic interiors of black holes.
• 18:12
  Speaker 2: They basically want to see if the music still plays
• 18:14
  Speaker 2: the same tune under the most extreme conditions the universe
• 18:17
  Speaker 2: can possibly offer.
• 18:18
  Speaker 3: Exactly. Their ultimate goal is to see if gravity can
• 18:21
  Speaker 3: be derived entirely and only from quantum information without making
• 18:27
  Speaker 3: any classical assumptions at all.
• 18:29
  Speaker 2: Wow.
• 18:30
  Speaker 3: If they can insert raw quantum data into one side
• 18:33
  Speaker 3: of the equation, and get the full robust equations of
• 18:36
  Speaker 3: general relativity, including all the quantum corrections out the other side,
• 18:41
  Speaker 3: they will have essentially found the absolute bedrock of reality.
• 18:45
  Speaker 3: It would be a monumental leap toward a complete unified
• 18:49
  Speaker 3: theory of quantum gravity.
• 18:51
  Speaker 2: Bridging that massive cosmic divide we talked about at the
• 18:55
  Speaker 2: very beginning.
• 18:55
  Speaker 3: Yeah, mending the fundamental fracture in physics once and for all.
• 18:59
  Speaker 2: It is truly breathtaking to consider. Let's trace the path
• 19:02
  Speaker 2: of this journey one more time to really cement how
• 19:05
  Speaker 2: far we've come. We started with the universe torn in two, right?
• 19:08
  Speaker 2: The smooth, heavy world of gravity and the jittery, unpredictable,
• 19:12
  Speaker 2: microscopic world of quantum mechanics. And for a century, the
• 19:15
  Speaker 2: math simply wouldn't allow them to exist in the same room.
• 19:18
  Speaker 3: Then the lens of classical thermodynamics gave us a clue,
• 19:22
  Speaker 3: sort of suggesting that gravity might just be an emergent
• 19:25
  Speaker 3: crowd effect, like the pressure inside a balloon.
• 19:28
  Speaker 2: And today, armed with the razor-sharp math of quantum relative entropy,
• 19:32
  Speaker 2: physicists have actually found the mechanism. By measuring how distinct
• 19:36
  Speaker 2: a piece of quantum information is at a cosmic boundary,
• 19:39
  Speaker 2: the energy shifts. The entropy changes.
• 19:42
  Speaker 3: Exactly.
• 19:43
  Speaker 2: The boundary physically warps to hold the data, and the
• 19:46
  Speaker 2: math of gravity naturally and inevitably emerges. the quantum matter
• 19:50
  Speaker 2: is the pluck the fabric of space is the string
• 19:54
  Speaker 2: and gravity is the music beautifully put space time and
• 19:57
  Speaker 2: gravity are not fundamental building blocks they are just the
• 20:00
  Speaker 2: shapes created by moving quantum data.
• 20:02
  Speaker 3: And it completely forces a rewrite of how we understand
• 20:05
  Speaker 3: our own existence and um If we follow this logic
• 20:09
  Speaker 3: all the way down, it leaves us with a truly
• 20:11
  Speaker 3: profound question to ponder long after we stop talking today.
• 20:15
  Speaker 2: What's that?
• 20:17
  Speaker 3: Well, if the physical curvature of the universe, the inescapable
• 20:20
  Speaker 3: gravity holding you to the Earth right now, is entirely
• 20:23
  Speaker 3: dictated by how distinguishable microscopic quantum states are from one another,
• 20:29
  Speaker 3: does that mean the solid physical world we interact with is,
• 20:32
  Speaker 3: at its most fundamental level, really just a complex web
• 20:36
  Speaker 3: of data?
• 20:37
  Speaker 2: Are we living in a universe made of physical matter?
• 20:40
  Speaker 2: Or are we just navigating a universe built entirely out
• 20:43
  Speaker 2: of math and memory?