Speaker 1: Welcome to the Core 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 something for a second. Imagine
Speaker 2: you're walking into a university physics lab. You walk past
Speaker 2: all the high tech equipment, you go over the professor's bookshelf,
Speaker 2: and you pull down a foundational one hundred and fifty
Speaker 2: year old textbook on how materials work, and you just
Speaker 2: toss it right out the window. Because essentially that is
Speaker 2: what just happened in the world of quantum physics.
Speaker 3: It really is. I mean, shattered is really the only
Speaker 3: word for it. We are looking at a breakthrough from
Speaker 3: April twenty twenty six, and this was spearheaded by researchers
Speaker 3: at the Indian Institute of Science in Bengaluru.
Speaker 2: Working alongside the National Institute from Material Science in Japan.
Speaker 3: Right exactly. Yeah, They managed to force electrons inside a
Speaker 3: simple piece of carbon to behave in a way that
Speaker 3: while classical physics dictates they simply shouldn't be able to.
Speaker 2: They observed electrons flowing inside this single layer of carbon,
Speaker 2: not like a gas of bouncing particles, which is what
Speaker 2: we've always been taught, but like a nearly perfect, frictionless liquid,
Speaker 2: which is wild. It's wild to even say out loud.
Speaker 2: So today our mission is to explore how this actually happened.
Speaker 2: We're going to look at how these electrons completely defied
Speaker 2: a golden rule of physics, and how they transformed into
Speaker 2: this bizarre fluid.
Speaker 3: Like state, and crucially what that means for the future.
Speaker 2: Right, what it means for the technology use every single day,
Speaker 2: not to mention our entire understanding of the universe. So okay,
Speaker 2: let's unpack this sounds good because to understand how you
Speaker 2: break a one hundred and fifty year old law, you
Speaker 2: first have to look at the scene of the crime,
Speaker 2: and in this case, that scene is arguably one of
Speaker 2: the most pristine, laboratory perfect materials ever created.
Speaker 3: Yeah, the stage for this whole phenomenon is graphene. For
Speaker 3: anyone who needs a quick visual just picture a single
Speaker 3: atomic layer of carbon atoms arranged in a hexagonal.
Speaker 2: Pattern like a microscopic honeycomb.
Speaker 3: Exactly, or chicken wire, and being only one atom sick
Speaker 3: makes it effectively a two dimensional material.
Speaker 2: I have to push back on the timeline here for
Speaker 2: a second, though, Yeah, because graphin was fantously isolated back
Speaker 2: in what two thousand and four?
Speaker 4: Yeah, two thousand, right, and people have.
Speaker 2: Been calling it a wonder material for two decades. So
Speaker 2: if we've known about graphine and its incredible properties for
Speaker 2: twenty years, why are we only seeing this completely mind
Speaker 2: bending behavior right now?
Speaker 4: That is the big question?
Speaker 2: Is it? I mean, is it like trying to observe
Speaker 2: a perfectly still reflection in a pond where you need
Speaker 2: absolute total stillness before the magic happens.
Speaker 3: The pod analogy is actually a great way to think
Speaker 3: about it, because for twenty years researchers have been looking
Speaker 3: into a pond that was just a little too rippled.
Speaker 3: Ah Okay, regular graphene, even when it's high quality, still
Speaker 3: has microscopic impurities. It has tiny defects in the carbon lattice.
Speaker 3: It even gets affected by the underlying substrate it sits on.
Speaker 2: So it's never truly perfect in a normal lab setting.
Speaker 1: Right.
Speaker 3: But the team in Bengaluru, led by professor Arndam Ghosh
Speaker 3: and PhD student Anikit Majimdar, they realized They couldn't just
Speaker 3: use regular graphine. They had to completely eliminate the wind
Speaker 3: causing those ripples.
Speaker 2: How do you even do that at an atomic level?
Speaker 3: Well, they took this incredibly pure graphene and they sandwiched
Speaker 3: it inside layers of a different material called hexagonal boron nitride.
Speaker 2: Oh wow. So they basically built a microscopic clean room
Speaker 2: around the graphene just to protect it from the outside world.
Speaker 4: Exactly.
Speaker 3: The boron nitride acts as a perfect shield. It strips
Speaker 3: away almost all the environmental interference, the impurities, and the defects.
Speaker 3: They needed this ultra clean environment to reach a very specific,
Speaker 3: highly delicate state called the direct point.
Speaker 2: The direct point that sounds like something straight out of
Speaker 2: a sci fi movie. What is physically happening at that point?
Speaker 3: So, in normal conditions, graphene has charge carriers. These are
Speaker 3: either electrons which carry a negative charge, or what physicists call.
Speaker 2: Holes holes like actual physical.
Speaker 3: Holes, not exactly. A hole is essentially the absence of
Speaker 3: an electron, but it acts like a positively charged particle.
Speaker 2: That's a bit trippy.
Speaker 3: Think of a bubble moving through water. The bubble itself
Speaker 3: is just empty space, right, yeah, but it moves and
Speaker 3: acts like a distinct physical thing.
Speaker 2: Okay, that makes sense.
Speaker 3: So the direct point is this highly specific charge neutral
Speaker 3: sweet spot. It's the exact transition point where graphine behaves
Speaker 3: neither fully as a metal nor as an insulator, because
Speaker 3: you have an equal number of electrons and holes perfectly
Speaker 3: balancing each other out.
Speaker 2: It's just sitting right on the fence.
Speaker 3: Sitting on the fence in an environment so perfectly clean
Speaker 3: and at such precise temperature conditions that the electrons basically
Speaker 3: undergo a fundamental identity crisis. What you mean, They stop
Speaker 3: acting as independent, solitary particles. Instead, they interact with each
Speaker 3: other so strongly that they merge their behaviors. They form
Speaker 3: a single collective mass.
Speaker 2: And because they stop acting like a bunch of loan
Speaker 2: individuals and become this collective crowd, they trigger this bizarre phenomenon,
Speaker 2: the one that completely breaks the golden rule of how
Speaker 2: metals handle heat and electricity.
Speaker 3: Yes, which brings us to that shattered textbook you mention, right.
Speaker 2: The eighteen fifties vitamin France law. Here's where it gets
Speaker 2: really interesting, because the Vitamin France law isn't some obscure footnote.
Speaker 2: It has been a bedrock principle of material science. Oh,
Speaker 2: if I understand it correctly. The law essentially says that
Speaker 2: in normal metals, thermal conductivity, so how well it conducts
Speaker 2: heat and electrical conductivity how well it conducts a charge,
Speaker 2: go hand in hand.
Speaker 3: They are proportional, they are completely linked, and they're governed
Speaker 3: by a universal constant called the Lorenz number.
Speaker 4: Yeah, in conventional.
Speaker 3: Materials like the copper wire running through your house, the
Speaker 3: exact sum electrons are responsible for carrying both the electrical
Speaker 3: charge and the thermal energy.
Speaker 2: So they do both jobs right.
Speaker 3: Naturally, if a material is good at conducting electricity, it's
Speaker 3: going to be proportionally good at conducting heat. The two
Speaker 3: processes are tied together by how the electrons scatter and
Speaker 3: collide within the material.
Speaker 2: I always picture it like a Buddy Cup movie. Heat
Speaker 2: and electricity are partners. They always ride in the same car,
Speaker 2: they go to the same places, they handle the exact
Speaker 2: same cases.
Speaker 3: That's a fun way to look at it.
Speaker 2: But in this ultra clean graphene experiment, for the very
Speaker 2: first time, the partners took separate cabs. They just completely
Speaker 2: went their own ways.
Speaker 3: Well, not quite separate cabs. Is actually more profound than that. Yeah,
Speaker 3: thing of the electrical charge as the cars themselves in
Speaker 3: a massive traffic jam, slowly inching forward together.
Speaker 2: Okay.
Speaker 3: The heat, on the other hand, is the sound of
Speaker 3: a heavy base from a car stereo rickling through the traffic.
Speaker 3: Oh wow, the physical cars, the charge, and the sound
Speaker 3: wave the heat are moving completely independently through the exact
Speaker 3: same system. What's fascinating here is the sheer scale of
Speaker 3: the separation, right, because.
Speaker 2: It wasn't just a tiny glitch, not at all.
Speaker 3: The researchers didn't just observe a slight deviation. They observed
Speaker 3: a massive two hundredfold violation of the weedam on.
Speaker 4: Frond's law two hundred times exactly.
Speaker 3: In this highly specific state. At the direct point, charge
Speaker 3: and heat completely decoupled as electrical conductivity went up, thermal
Speaker 3: conductivity actually went down, and vice versa.
Speaker 2: They moved in completely opposite directions. But wait, if the
Speaker 2: electrons are the physical vehicles carrying both the charge and
Speaker 2: the heat, how on earth are they separating the two?
Speaker 2: How does the base separate from the.
Speaker 3: Car Because they can't shed heat by crashing into the
Speaker 3: walls or impurities anymore in normal metals, An electron hits
Speaker 3: a defect, loses energy and generates heat locally here. Because
Speaker 3: the material is flawlessly clean, the energy has to go
Speaker 3: so where else. It gets absorbed into the collective momentum
Speaker 3: of the group, So.
Speaker 2: The whole blob is just carrying the energy together sort of.
Speaker 3: The electrical charge is still tied to the physical slow
Speaker 3: movement of this collective blob of electrons, but the thermal energy,
Speaker 3: the heat, starts traveling as a collective wave, rippling rapidly
Speaker 3: through the fluid, independent of how fast the blob itself
Speaker 3: is moving.
Speaker 2: That completely flies in the face of classical physics.
Speaker 3: Oh, classical physics completely fails to explain what's happening. The
Speaker 3: researchers realize that even though the heat and charge had uncoupled,
Speaker 3: their behavior still perfectly followed a material independent universal quantum.
Speaker 4: Constant, meaning what exactly it means.
Speaker 3: They were no longer looking at classical scattering. They were
Speaker 3: observing quantum critical behavior. The system is sitting at a
Speaker 3: tipping point governed by deep quantum fluctuations rather than classical mechanics.
Speaker 2: Let me make sure I'm wrapping my head around this.
Speaker 2: We've got electrons that have merged into a collective crowd.
Speaker 2: The heat is rippling through them like a sound wave,
Speaker 2: while the electrical charges moving as a physical group. But
Speaker 2: how are they actually moving through the material to allow
Speaker 2: this to happen. That's the key, because earlier you mentioned
Speaker 2: they stopped acting like independent particles and started acting like
Speaker 2: a liquid. Right.
Speaker 3: This phenomenon is known as hydrodynamic transport. Let's compare it
Speaker 3: to normal electricity again. Okay, In an ordinary copper wire,
Speaker 3: electrons act like a gas. They move independently, constantly crashing
Speaker 3: into things. They crash into impurities in the metal, or
Speaker 3: they crash into the physical vibrations of the atoms themselves.
Speaker 4: You're called phonons, right, yes, phonons.
Speaker 3: Every time an electron crashes, it loses energy, generates heat,
Speaker 3: and creates what we call electrical resistance.
Speaker 2: So instead of electrons playing a chaotic game of pinball
Speaker 2: and bouncing off the bumpers, lighting up the board, generating.
Speaker 3: Key exactly, they don't do that here.
Speaker 2: In this ultra clean graphene. There are virtually no bumpers to.
Speaker 4: Hit, none at all.
Speaker 3: The mean free path, which is the distance an electron
Speaker 3: can travel before hitting something, changes drastically. Instead of hitting impurities,
Speaker 3: the electrons start bumping into each other far more often
Speaker 3: than they hit anything else.
Speaker 2: Wait, if there are no impurities to crash into, shouldn't
Speaker 2: they just shoot in a perfectly straight line at the
Speaker 2: speed of light? Why are they bumping into each other?
Speaker 3: Because they are packed into such a pristine, confined two
Speaker 3: dimensional space, the forces between the electrons themselves become the
Speaker 3: dominant interaction.
Speaker 2: Oh, so they link arms and flow like a rushing river.
Speaker 3: That's exactly it. Instead of flying straight, they continuously deflect
Speaker 3: off one another, exchanging momentum. They enter a state of
Speaker 3: hydrodynamic flow, moving as a single viscous liquid.
Speaker 4: That is wild, and it gets better.
Speaker 3: The researchers observe that this direct fluid has a viscosity
Speaker 3: roughly one hundred times lower than water. It is approaching
Speaker 3: the theoretical limit of a perfect fluid, which is a
Speaker 3: fluid with near zero internal friction.
Speaker 2: Near zero friction. So they are just effortlessly gliding through
Speaker 2: the carbon.
Speaker 3: Lattice, gliding, but with complex fluid dynamics. Because they are
Speaker 3: acting collectively, Microscopic whirlpools and vortices of electrons form inside
Speaker 3: the graphene.
Speaker 2: Rural pools of electrons.
Speaker 3: Yeah, just like water swirling around a rock in a stream,
Speaker 3: the current folds back on itself in tiny eddies.
Speaker 2: That is deeply strange. Yeah, microscopic whirlpools of electricity.
Speaker 4: It gets stranger.
Speaker 2: I don't know if my brain can handle stranger.
Speaker 3: Well, because we are at the direct point. These electrons
Speaker 3: aren't just acting like a liquid. They are behaving like massless,
Speaker 3: relativistic particles. They are mimicking the behavior of particles moving
Speaker 3: at the speed of light.
Speaker 2: Okay, yep, my brain is starting to melt a little bit.
Speaker 2: Massless relativistic particles swirling in frictionless whirlpools. Where else in
Speaker 2: the universe does something like that even exist?
Speaker 3: If we connect this to the bigger picture, the only
Speaker 3: other places we see perfect fluids with these kinds of
Speaker 3: relativistic massless properties are in the most extreme violent environments imaginable,
Speaker 3: like where we see it in the cork gluon plasma.
Speaker 3: But what It's the primordial soup of highly energetic subatomic
Speaker 3: particles that existed fractions of a second after the Big Bang. Normally,
Speaker 3: scientists have to use the massive particle accelerators at CERN
Speaker 3: in Switzerland. You know, smashing atoms together at near light
Speaker 3: speed just to catch a tiny glimpse of it.
Speaker 2: Wait, you're telling me this pencil lead acts like a
Speaker 2: multi billion dollars SuperCollider.
Speaker 4: I am.
Speaker 3: The behavior of this direct fluid in graphene is mathematically
Speaker 3: linked to something called holographic duality, which is inspired by
Speaker 3: black hole physics in string theory.
Speaker 2: Okay, you're gonna have to break that down for me.
Speaker 3: To put it simply, the mathematical equations we use to
Speaker 3: describe the thermodynamics of a three dimensional black hole perfectly
Speaker 3: match the math describing the flow of electrons on this
Speaker 3: two dimensional sheet of carbon. It's like looking at a
Speaker 3: mathematical hologram.
Speaker 2: So physicists don't need to look into deep space or
Speaker 2: smash atoms underground to study the edge of a black hole.
Speaker 2: They could just put a perfectly clean piece of graphene
Speaker 2: on a table in a lap.
Speaker 3: Basically, yeah, graphene has become a tabletop laboratory for simulating
Speaker 3: the extreme universe. It gives researchers an incredibly accessible way
Speaker 3: to test theories about quantum entanglement and cosmic thermodynamics without
Speaker 3: building impossible machines.
Speaker 2: That is a staggering wind for theoretical physics, but as
Speaker 2: amazing as simulating the Big Bang on a desk is
Speaker 2: what brings back down to Earth for a second. So
Speaker 2: what does this all mean? If you're listening to this
Speaker 2: on a smartphone, you're probably wondering why your phone still
Speaker 2: gets hot and what this frictionless, quantum river of electrons
Speaker 2: actually changes for you.
Speaker 3: It changes everything about how we design the physical architecture
Speaker 3: of electronics because the biggest enemy of modern technology is
Speaker 3: energy dissipation, which we experience as heat. Whenever you use
Speaker 3: your smartphone, your laptop, or an electric vehicle, the electrical
Speaker 3: resistance inside the components generates heat. It drains your battery,
Speaker 3: slows down processing speeds, and requires bulky cooling systems.
Speaker 2: Yeah, I mean, if I play a heavy video game
Speaker 2: on my phone, within ten minutes, the back of it
Speaker 2: is burning hot. That's the pinball game of electrons smashing
Speaker 2: into impurities exactly.
Speaker 3: Now, imagine if the electricity inside your devices could move
Speaker 3: through pathways using hydrodynamic flow like the river right near.
Speaker 3: Frictionless electron flow paves the way for ultra low power electronics.
Speaker 3: Electricity could move with practically zero energy dissipation. Your phone
Speaker 3: wouldn't overheat. Oh wow, The battery life would be extended
Speaker 3: dramatically because you aren't bleeding out energy as heat. Processing
Speaker 3: power could skyrocket because chip designers wouldn't have to worry
Speaker 3: about melting the microchips.
Speaker 2: Bypassing the friction of standard electricity is a trillion dollar
Speaker 2: industry shift all on its own.
Speaker 3: Oh absolutely, But that's just the beginning. The direct fluid
Speaker 3: is incredibly sensitive to its environment. The sensitivity will enable
Speaker 3: the creation of next generation quantum sensors.
Speaker 4: What kind of sensors we are talking about?
Speaker 3: Sensors that can amplify unimaginably faint electrical signals or detect
Speaker 3: minuscule magnetic fields with a level of precision we've never
Speaker 3: had before.
Speaker 2: Where would we practically use sensors that sensitive?
Speaker 3: It could absolutely revolutionize medical imaging. Right now, an MRI
Speaker 3: machine requires massive room size superconducting magnets cooled by liquid
Speaker 3: helium just to pick up the faint magnetic signals from
Speaker 3: your body, and.
Speaker 2: They are incredibly loud and claustrophobic exactly.
Speaker 3: But if we have a perfectly frictionless quantum sensor, it
Speaker 3: could potentially pick up the magnetic field of a single
Speaker 3: firing neuron in the brain without needing those giant magnets.
Speaker 2: That's unbelievable.
Speaker 3: It also changes navigation systems, making them hyperaccurate, even deep
Speaker 3: underwater or underground where GPS signals can't reach.
Speaker 2: What about the decoupling of heat and electricity. We talked
Speaker 2: earlier about the heat wave separating from the electrical charge. Yeah,
Speaker 2: they aren't partners anymore. There has to be a way
Speaker 2: to exploit that in engineering, right there is.
Speaker 3: Because heat and charge are now decoupled, we can create
Speaker 3: vastly improved thermoelectric.
Speaker 4: Devices which do what exactly.
Speaker 3: These are devices that turn temperature differences directly into electricity,
Speaker 3: or use electricity to move heat. Think about a solid
Speaker 3: state refrigerator. Currently, if you use electricity to push heat
Speaker 3: out of a conductive material, the heat naturally wants to
Speaker 3: leak right back through because the two properties are linked.
Speaker 4: It's an engineering nightmare.
Speaker 2: But if they are decoupled, you can pump the heat
Speaker 2: out and it won't drag the electrical charge backward with it.
Speaker 3: You've got it. You can build incredibly efficient systems for
Speaker 3: harvesting waste heat from massive server farms or industrial plants
Speaker 3: and turn that directly into usable power.
Speaker 2: That would be huge for green energy.
Speaker 3: Absolutely, you could have household refrigerators with zero moving parts,
Speaker 3: no chemical coolants, and perfect efficiency. Furthermore, all of this
Speaker 3: position's graphene to accelerate research into hybrid quantum classical computers.
Speaker 2: Oh merging quantum computers with regular ones.
Speaker 3: Right, it acts as the perfect bridge material between delicate
Speaker 3: que bits and standard electronics.
Speaker 2: It feels like this single April twenty twenty six discovery
Speaker 2: just kicked open fifty different doors at exactly the same time.
Speaker 3: It really did, And this raises an important question for
Speaker 3: the global scientific community. How quickly can we rewrite the
Speaker 3: textbooks and adapt our manufacturing?
Speaker 2: Yeah? How long will that take?
Speaker 3: It's hard to say, But this publication in Nature Physics
Speaker 3: isn't just a fun quirk of a material.
Speaker 4: It is a blueprint.
Speaker 3: It shows us that if we can harness hydrodynamic electron
Speaker 3: flow at a commercial scale, the electronics of twenty forty
Speaker 3: are going to look as alien to us today as
Speaker 3: a smartphone would look to someone from eighteen fifty.
Speaker 2: Wow, let's take a breath and just recap this year's
Speaker 2: scale of the journey we've been on. We started with
Speaker 2: a single impossibly pure layer of carbon atoms. By protecting
Speaker 2: it flawlessly from the outside world, scientists allowed the electrons
Speaker 2: inside to hit this magical charge neutral diract point, and
Speaker 2: instead of shooting around like chaotic pinballs, the electrons merged
Speaker 2: into a frictionless quantum.
Speaker 3: Ver beautifully summarized.
Speaker 2: In doing so, they completely shattered one hundred and fifty
Speaker 2: year old law of physics, proving that heat and electricity
Speaker 2: don't always have to travel together exactly. The result is
Speaker 2: a phenomenon that not only promises to revolutionize our computers,
Speaker 2: our batteries, and our medical devices, but also lets physicists
Speaker 2: simulate the violent mechanics of black holes in the Big
Speaker 2: Bang right on a tabletop.
Speaker 3: It's a humbling reminder that nature always has more tricks
Speaker 3: up its sleeve. We thought we understood metals, and we
Speaker 3: thought we fully understood graphene, But when probed with sufficient
Speaker 3: purity and precision, we realized we had barely scratched the surface.
Speaker 2: That actually brings me to a final thought. I want
Speaker 2: to leave you with. Consider this the deepest, most violent
Speaker 2: secrets of the cosmos, The chaotic, swirling soup of the
Speaker 2: Big Bang. The incomprehensible math at the edge of a
Speaker 2: black hole. They aren't just out there in the deep,
Speaker 2: untouchable reaches of space, oh not. The exact same behavior
Speaker 2: can perfectly mirror itself inside a single layer of carbon,
Speaker 2: Essentially pens lad sitting quietly on a desk in a laboratory.
Speaker 2: It makes you wonder if a material we've known about
Speaker 2: and studied relentlessly for over two decades can still hide
Speaker 2: something this profound. What other universe breaking secrets are hiding
Speaker 2: in plain sight, just waiting to be found in the
Speaker 2: everyday materials all around us.
Speaker 3: The universe is always waiting to surprise you, as long
Speaker 3: as you know exactly how to look.
Speaker 2: Thank you so much for joining us on this exploration today.
Speaker 2: Keep questioning the world around you, because clearly even the oldest,
Speaker 2: most trusted textbooks don't have all the answers. See you
Speaker 2: next time.