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: If I asked you to say, park your car in
Speaker 2: the driveway, but told you that making the car perfectly
Speaker 2: still meant you would completely lose track of where you
Speaker 2: parked it, I mean, you'd probably think I was losing my.
Speaker 3: Mind, right, Oh, absolutely, I'd think you were crazy.
Speaker 2: Right, But if your car was the size of an electron,
Speaker 2: that is the literal inescapable reality you would face.
Speaker 3: Yeah, it completely apends our basic intuition. Like we are
Speaker 3: conditioned from birth basically to believe that the physical world
Speaker 3: is concrete.
Speaker 2: Right, like a billiard ball is just sitting there exactly.
Speaker 3: We think that, And if we simply look closely enough
Speaker 3: or use a sensitive enough instrument, we can ten down
Speaker 3: every single detail about an object's state.
Speaker 2: But the universe epically has a hard coded speed limit
Speaker 2: on certainty. Nature fundamentally, at its very core, refuses to
Speaker 2: let us know everything all at once.
Speaker 3: Yeah, And it's a concept known as the Heisenberg uncertainty principle.
Speaker 2: Right, which sounds super academic.
Speaker 3: It does, but it's far more than a quirky mathematical footnote.
Speaker 3: I mean, this principle is the structural scaffolding of reality. Yeah,
Speaker 3: the refusal of the universe to be pinned down is
Speaker 3: while it's the only reason solid matter can exist in
Speaker 3: the first place.
Speaker 2: Okay, let's unpack this because to understand the mechanics of reality,
Speaker 2: we have to zoom down to the incredibly tiny scale
Speaker 2: of atoms and electrons. I really do, and down there,
Speaker 2: reality operates on a strict cosmic trade off between two
Speaker 2: specific properties. So the first is position, which is exactly
Speaker 2: where our particle is located in space, and the second
Speaker 2: is momentum, which is essentially a combination of how fast
Speaker 2: that particle is moving, the direction is traveling, and its mass. Aha.
Speaker 2: And the paradox that completely breaks my brain is that
Speaker 2: knowing one of these properties just entirely destroys your ability
Speaker 2: to know the other.
Speaker 3: It really does.
Speaker 2: If you isolate an electron's exact location, it's momentum becomes
Speaker 2: just wildly erratic. You have zero idea how fast it's going.
Speaker 3: Yeah, completely lost.
Speaker 2: But if you measure its momentum perfectly. Its position blurs
Speaker 2: out into this massive range of possibilities. You literally cannot
Speaker 2: find it.
Speaker 3: Simply stating the rule almost does a disservice to how
Speaker 3: bizarre the phenomenon actually is.
Speaker 2: Honestly, Oh, for sure.
Speaker 3: To really grasp the mechanics of this, this fuzziness, we
Speaker 3: need to visualize the trade off. We need to look
Speaker 3: at how we try to capture motion in our everyday world.
Speaker 2: Yeah, and I always think about trying to photograph a
Speaker 2: speeding race car on a dark track.
Speaker 3: Oh, that's a great way to picture it, right.
Speaker 2: You have a camera and you are forced to make
Speaker 2: a choice about your shutter speed. So if you dial
Speaker 2: in a super fast shutter speed, the shutter snaps open
Speaker 2: and shut in a fraction of a millisecond, freezing the
Speaker 2: action exactly. You freeze the car perfectly. You get a
Speaker 2: crystal clear, razor sharp image of the car's exact position
Speaker 2: on the track at that exact moment.
Speaker 3: But of course, because the exposure was so brief, there's
Speaker 3: zero motion blur.
Speaker 2: Right, there is no blur at all, So looking at
Speaker 2: that frozen frame, you cannot tell if the car was going,
Speaker 2: you know, two hundred miles an hour, or if it
Speaker 2: was just parked on the track.
Speaker 3: You have no context for the speed.
Speaker 2: Yeah, you secured perfect position, but you sacrificed all information
Speaker 2: about its momentum. And conversely, a slow shutter speed gives
Speaker 2: you the motion blur to see the speed, but the
Speaker 2: car is just a long streak. Yeah, you don't know
Speaker 2: where it actually is at any given microsecond.
Speaker 3: What's fascinating here is that the mechanical limit of a
Speaker 3: camera is a great starting point, but nature takes the
Speaker 3: limitation a massive step further. Oh so, well, in photography,
Speaker 3: you could theoretically build a like imagine ratear camera hybrid
Speaker 3: to capture both speed and position simultaneously.
Speaker 2: Right, yeah, just use better technology exactly.
Speaker 3: The limitation is merely technological. But in the quantum realm,
Speaker 3: the lack of information isn't a failure of our tools.
Speaker 3: Oh wow, Yeah, a quantum particle literally does not possess
Speaker 3: a sharply defined location and a sharply defined velocity at
Speaker 3: the same time. The information itself just does not simultaneously
Speaker 3: exist in the universe.
Speaker 2: Wait, if it's not a camera limitation and the particle
Speaker 2: is actually physically blurry, what is the universe made of
Speaker 2: that allows a physical object to just be a blur.
Speaker 2: That's the big question because if I picture an electron,
Speaker 2: I picture like a tiny hard billiard ball, and a
Speaker 2: billiard ball is always somewhere.
Speaker 3: Right, and that intuition the tiny billiard ball is exactly
Speaker 3: what we have to discard, cost it out, toss it
Speaker 3: completely out. To understand why a particle can be physically blurry,
Speaker 3: we have to look at wave particle duality.
Speaker 2: Okay, the double life thing.
Speaker 3: Yeah, everything at the foundational level of reality, Electrons, photons, quirks,
Speaker 3: it all lives a double life. They exhibit properties of
Speaker 3: a localized dot, but they also propagate through space like
Speaker 3: a spread out ripple.
Speaker 2: And this is the wave function, right, Yes.
Speaker 3: They're described by a wave function, which is a mathematical
Speaker 3: description of probabilities determining where they might interact and how
Speaker 3: they move.
Speaker 2: Hold on, I'm struggling to picture that. How can a
Speaker 2: physical object with mass be a ripple? Are you saying
Speaker 2: my physical body is ultimately made up of probability ripples at.
Speaker 3: The most fundamental level, Yes, that is nuts.
Speaker 2: It is.
Speaker 3: Think about an ocean wave rolling toward a beach. Imagine
Speaker 3: a series of very long, gentle continuous.
Speaker 2: Waves, okay, picturing it.
Speaker 3: Because those waves are spread out over a vast distance
Speaker 3: with clear repeating peaks and troughs, you can easily measure
Speaker 3: their wavelength and.
Speaker 2: Speed, so you know exactly what they're doing.
Speaker 3: Right. You can calculate the momentum of the wave system beautifully.
Speaker 3: But if I ask you to point your finger to
Speaker 3: the single exact millimeter where the wave is located, you can't.
Speaker 2: Right.
Speaker 3: The wave stretches over miles.
Speaker 2: Of ocean because the wave isn't an object. It's a
Speaker 2: pattern of motion spread out over space exactly.
Speaker 3: Now consider the opposite scenario. Imagine dropping a tiny pebble
Speaker 3: into a perfectly still pond, creating a single, sharp, vertical splash.
Speaker 2: Okay, so just one tiny spike yep, for.
Speaker 3: A fraction of a second, you have a very localized
Speaker 3: sharp peak. You know the exact position of that disturbance.
Speaker 2: But I'm guessing you lose the wave pattern exactly.
Speaker 3: If you try to measure the overarching speed or frequency
Speaker 3: of that single spike, you run into a mathematical wall.
Speaker 3: There are no repeating troughs and peaks to measure. Oh,
Speaker 3: I see, the pattern of motion is entirely undefined. Because
Speaker 3: the disturbance is restricted to one tiny spot. To get
Speaker 3: a perfectly sharp position, nature has to squeeze.
Speaker 2: The wave, and squeezing it ruins it.
Speaker 3: Yeah, Squeezing the wave destroys the repeating pattern, which inherently
Speaker 3: scrambles the momentum.
Speaker 2: Does this happen with other types of waves? Because I
Speaker 2: feel like I've experienced something similar when messing around with
Speaker 2: audio editing software.
Speaker 3: Oh. Sound is actually the perfect medium to illustrate the
Speaker 3: underlying math. Think about a singer holding a sustained, pure
Speaker 3: musical note.
Speaker 2: Here's where it gets really interesting. Because a pure musical note,
Speaker 2: like say an a vibrating at exactly four hundred and
Speaker 2: forty hertz, has an exact frequency, which is our momentum.
Speaker 2: Right in our analogy, that frequency represents perfect momentum. Yeah,
Speaker 2: But to hear that pure, exact pitch, the singer has
Speaker 2: to hold the note over time.
Speaker 3: The sound way has to ring out exactly.
Speaker 2: It has to ring out so your ear can process
Speaker 2: the repeating cycles. If I ask what exact single microsecond
Speaker 2: did that note exist, the question itself is just flawed.
Speaker 3: It doesn't make sense to ask, right.
Speaker 2: A frequency requires a span of time to exist. The time,
Speaker 2: or the pefission is spread out.
Speaker 3: The pitch is pristine, but the timing is fundamentally decentralized.
Speaker 2: But if I want to perfectly define the timing, say
Speaker 2: a sharp sudden snare drum click, I know the exact
Speaker 2: millisecond that click happened.
Speaker 3: You have perfect position.
Speaker 2: Yes, perfect position, But a sharp click like that doesn't
Speaker 2: have a discernible musical pitch. A sudden burst of sound
Speaker 2: is actually a chaotic jumble of thousands of different frequencies
Speaker 2: all stacked on.
Speaker 3: Top of each other, just massive overlap.
Speaker 2: Right, So to get a sharp position in time, nature
Speaker 2: has to mix a massive variety of different wavelengths together.
Speaker 2: And since wavelength dictates momentum, mixing all those wavelengths together
Speaker 2: inherently scrambles the momentum. Y you get a pinpoint location,
Speaker 2: but a completely chaotic blurry speed.
Speaker 3: The audio analogy flawlessly maps to quantum mechanics. What physicists
Speaker 3: call a narrow wave packet, which is basically a localized particle,
Speaker 3: is constructed by overlapping countless different waves.
Speaker 2: So it's like a snare, drume click made of probability.
Speaker 3: That's a great way to put it. The mathematics of
Speaker 3: waves dictates that you cannot have a single point of
Speaker 3: disturbance without adding together an infinite number of different frequencies.
Speaker 2: I think a natural human reaction into all this weirdness
Speaker 2: is just to assume we're doing the measuring wrong.
Speaker 3: Oh, constantly, people always assume that, right.
Speaker 2: We think, Okay, an electron is incredibly tiny. If I
Speaker 2: try to look at it under a microscope, I have
Speaker 2: to bounce light off it, and shooting a photon of
Speaker 2: light at an electron is going to physically knock the
Speaker 2: electron off course.
Speaker 3: Like a collision.
Speaker 2: Yeah, it's like trying to figure out where a moth
Speaker 2: is in a dark room by throwing tennis balls at it.
Speaker 2: You might find them off, but you've completely ruined its
Speaker 2: flight patist in the process.
Speaker 3: You are describing the observer effect, which is incredibly common.
Speaker 3: But it is a massive misconception to equate that with
Speaker 3: Heisenberg's principle.
Speaker 2: Oh really, so they aren't the same thing.
Speaker 3: Not at all. Measurement absolutely disturbs quantum systems, Yes, but
Speaker 3: Heisenberg's uncertainty principle is not about clumsy human tools.
Speaker 2: It's deeper than that, much deeper.
Speaker 3: Even in a purely theoretical universe where we possess a magical,
Speaker 3: perfectly gentle, completely non invasive way to measure a particle,
Speaker 3: the trade off remains absolute. The uncertainty is woven into
Speaker 3: the wave function itself, long before any human being or
Speaker 3: instrument enters the room. The universe itself does not know
Speaker 3: both values perfectly.
Speaker 2: I have to push back here on behalf of anyone
Speaker 2: looking out their window right now.
Speaker 3: Go for it.
Speaker 2: If this is an inescapable rule of nature and the
Speaker 2: universe doesn't know where things are, why is my car
Speaker 2: a blurry wave of probabilities?
Speaker 3: Ah? The macro question, right.
Speaker 2: I know exactly where my car is parked, and I
Speaker 2: know its speed is exactly zero. It's not smeared out
Speaker 2: across my driveway. How can the fundamental building blocks of
Speaker 2: reality be blurry but the objects they build are perfectly sharp.
Speaker 3: The resolution to that paradox lies in a fundamental limit
Speaker 3: called Plank's.
Speaker 2: Constant planks constant.
Speaker 3: Yeah, you can think of planks constant as the minimum
Speaker 3: pixel size of the universe's resolution. It dictates the minimum
Speaker 3: amount of fuzziness that must exist when position and momentum
Speaker 3: are combined.
Speaker 2: And I'm assuming that pixel size is small.
Speaker 3: It is unimaginably tiny. In the macroscopic world of cars, baseballs,
Speaker 3: and human bodies, the mass of the objects is astronomically
Speaker 3: large compared to the quantum scale. Okay, because your car
Speaker 3: has so much mass, the corresponding uncertainty and its momentum
Speaker 3: translates to a physical blur that is vastly smaller than
Speaker 3: the width of a single atom. Wait.
Speaker 2: Wait, so the car actually is blurry. My eyes just
Speaker 2: can't resolve the pixels.
Speaker 3: Yes, the fuzziness is there, but for all practical human
Speaker 3: purposes it is totally irrelevant.
Speaker 2: That is wild.
Speaker 3: It is only when you shrink down to the microscopic scale,
Speaker 3: when you look at a single electron whose mass is
Speaker 3: almost nothing, that this tiny amount of built in fuzziness
Speaker 3: suddenly dominates the entire system. It takes over exactly at
Speaker 3: the atomic scale. The pixel size is larger than the
Speaker 3: object itself.
Speaker 2: Realizing that the foundation's reality is fundamentally pixelated and fuzzy
Speaker 2: couldn't have gone over well with classical physicists. I mean
Speaker 2: they like things need.
Speaker 3: Oh it triggered an intellectual earthquake. We have to step
Speaker 3: back to the year in nineteen twenty seven, Werner Heisenberg
Speaker 3: was working alongside giants like Nils Bohr and Erwin Schrdinger.
Speaker 2: Yeah, heavy hitters.
Speaker 3: The biggest and up until that moment, the prevailing belief
Speaker 3: in science was Newtonian determinism.
Speaker 2: Basically, the universe as a machine.
Speaker 3: Yes, the universe was viewed as an incredibly complex, perfectly
Speaker 3: precise clock. The core assumption was that if a supremely
Speaker 3: intelligent being knew the exact position and the exact velocity
Speaker 3: of every single atom in the universe right now, they
Speaker 3: could plug those numbers into Newton's equations and perfectly calculate
Speaker 3: the entire future of the cosmos.
Speaker 2: Wait, if the universe is just a clockwork machine of
Speaker 2: cause and effect, If the starting position of every atom
Speaker 2: perfectly determines where it will bounce next, that implies a
Speaker 2: completely determined.
Speaker 3: Destiny, a set path.
Speaker 2: Yeah, that would mean every thought I have and every
Speaker 2: action I take was mathematically predetermined by the state of
Speaker 2: the universe billions of years ago. Exactly That effectively kills
Speaker 2: the concept of free will.
Speaker 3: The philosophical implications of a clockwork universe are deeply unsettling,
Speaker 3: but Heisenberg's uncertain principle proved that a clockwork universe is mathematically.
Speaker 2: Impossible because of the blur.
Speaker 3: Because of the blur, because you cannot know the exact
Speaker 3: position and velocity of even one single particle, a little
Speaker 3: in all of them, the future is fundamentally open. Wow,
Speaker 3: there is an irreducible randomness, a core in determinacy at
Speaker 3: the foundation of reality. The universe cannot perfectly predict its
Speaker 3: own future.
Speaker 2: So what does this all mean for reality itself?
Speaker 1: Like?
Speaker 2: Wait, does this mean the universe itself doesn't even know
Speaker 2: what it's doing? Next? Is reality not fully real until
Speaker 2: we look at it? Are we just walking around in
Speaker 2: a cloud of unrevolved probabilities?
Speaker 3: This raises an important question, and it is the exact
Speaker 3: dilemma that fractured the physics community into different philosophical camps.
Speaker 3: How does reality resolve the blur? Heisenbergen bor developed what
Speaker 3: is known as the Copenhagen interpretation. They argue that these
Speaker 3: properties literally do not possess concrete values until an interaction
Speaker 3: or measurement forces them to.
Speaker 2: Okay, so before that.
Speaker 3: The electron exists purely as a smeared up probability cloud,
Speaker 3: But the moment it hits a detector, The universe essentially
Speaker 3: rolls the dice, and the cloud instantly collapses into a
Speaker 3: definite location.
Speaker 2: That implies the active measurement forces the universe to make
Speaker 2: a decision. The probability suddenly snaps into reality.
Speaker 3: Yeah, and many physicists, including Einstein, hated the idea of
Speaker 3: the universe playing dice.
Speaker 2: I mean, I kind of get why.
Speaker 3: It's unsettling, so they explored alternative frameworks to handle the blur.
Speaker 3: One of the most fascinating is the many world interpretation.
Speaker 2: Oh, I've heard of this. The multiverse stuff exactly.
Speaker 3: Many worlds argues that the wave function never actually collapses. Instead,
Speaker 3: when a fuzzy, uncertain electron interacts with a detector, the
Speaker 3: electron doesn't choose just one location, It chooses all of them.
Speaker 3: It occupies every possible location. But to accommodate that, reality
Speaker 3: itself fractures. The universe splits into multiple branching timelines, one
Speaker 3: universe for every possible position the electron could have taken.
Speaker 2: So in many worlds, the uncertainty is just an illusion
Speaker 2: based on our limited perspective. The electron has a definite position,
Speaker 2: but we only get to see the timeline where it
Speaker 2: landed in spot A, while another version of us sees
Speaker 2: it in spot B.
Speaker 3: Exactly. The mechanics of how reality handles the paradox very
Speaker 3: wildly depending on the interpretation. But the crucial takeaway for
Speaker 3: you listening right now is that, regardless of whether you
Speaker 3: prefer collapsing probability clouds or branching multiverses, the Heisenberg uncertainty
Speaker 3: relation itself remains an experimentally confirmed bedrock fact.
Speaker 2: The blur is real.
Speaker 3: The physical trade off is absolutely real. No matter what
Speaker 3: underlying story you tell to explain the philosophy.
Speaker 2: As mine bending as the philosophy is, I always look
Speaker 2: for the tangible application. Does this quantum fuzziness actually dictate
Speaker 2: our physical, everyday existence?
Speaker 3: Oh, it is the sole reason you exist in the
Speaker 3: physical form you do right now? Wait, really, truly to
Speaker 3: see the physical impact, we just have to look at
Speaker 3: the stability of an atom. How do you normally picture
Speaker 3: the structure.
Speaker 2: Of an atom like a miniture solar system. Usually the
Speaker 2: heavy nucleus is the Sun in the center, and the
Speaker 2: tiny electrons are the planets orbiting around it.
Speaker 3: Right, the classic textbook drawing that classical model is physically
Speaker 3: impossible without quantum mechanics. Why if an electron or a
Speaker 3: tiny classical planet orbiting a positively charged nucleus, electromagnetic theory
Speaker 3: dictates it would constantly radiate energy, it would quickly lose
Speaker 3: speed and spiral incredibly fast right into the center, collapsing
Speaker 3: the atom entirely.
Speaker 2: Wait, so if an electron spiral perfectly into the tiny
Speaker 2: point of the nucleus and just sat there at the center,
Speaker 2: it would have an exact microscopic position exactly and because
Speaker 2: it's stopped at the center, its momentum would be exactly zero,
Speaker 2: which Heisenberg's principle absolutely forbids.
Speaker 3: The puzzle pieces are snapping together, oh.
Speaker 2: My gosh, because nature refuses to let the electron occupy
Speaker 2: that tiny exact space, trying to squeeze the electrons position
Speaker 2: forces its momentum to become wildly uncertain. The closer it
Speaker 2: gets to the nucleus, the more its momentum spikes, violently
Speaker 2: pushing it back out. So the solid structure of our
Speaker 2: bodies is literally held up by the fact that electrons
Speaker 2: physically refuse to be pinned down.
Speaker 3: If we connect this to the bigger picture, you have
Speaker 3: just described the mechanism of the physical universe that is incredible.
Speaker 3: It really is. The refusal to be certain provides the
Speaker 3: outward pressure that keeps atoms plump and stable. It is
Speaker 3: the invisible force keeping all matter from collapsing in on itself.
Speaker 3: And understanding that inherent fuzziness is the only way we
Speaker 3: have been able to build the modern technological.
Speaker 2: World, well, it limits what we can build. Yeah, right,
Speaker 2: because if engineers are trying to make computer chips smaller
Speaker 2: and faster, they eventually hit the pixel size of the universe.
Speaker 3: They do, and the modern semiconductor industry fights a daily
Speaker 3: war against Heisenberg's principle I bit inside your computer. Billions
Speaker 3: of microscopic transistors act as gates, trapping or releasing electrons
Speaker 3: to process information. For decades, engineers have been shrinking these
Speaker 3: gates to make computers faster.
Speaker 2: But there's a limit.
Speaker 3: Exactly as the gates become impossibly small, the physical space
Speaker 3: and electron is allowed to occupy becomes highly constricted.
Speaker 2: You're tightened the grip on its position.
Speaker 3: And as the position becomes highly restricted, the electron's momentum
Speaker 3: becomes wildly uncertain. It gains so much uncertain energy that
Speaker 3: it literally breaches the physical walls of the transistor.
Speaker 2: It just phases through.
Speaker 3: It performs what we call quantum tunneling. It teleports across
Speaker 3: the barrier simply because its wave function became too squeezed.
Speaker 3: Our entire digital infrastructure relies on engineers mathematically predicting and
Speaker 3: managing this fundamental blur.
Speaker 2: We've gone from trying to photograph race cars in the
Speaker 2: dark to mixing sound waves to build a physical object.
Speaker 3: It's quite a journey, it is.
Speaker 2: We learned that the universe has a fundamental pixel size
Speaker 2: that killed the idea of a predictable clockwork reality. And
Speaker 2: to top it off, this exact quantum fuzziness is the
Speaker 2: inward pressure keeping our atoms from imploding while sign ultaneously
Speaker 2: causing headaches for the engineers trying to build faster cell phones.
Speaker 3: The universe is funny that way.
Speaker 2: It keeps our universe wonderfully unpredictable and perfectly solid at
Speaker 2: the exact same time.
Speaker 3: The depth of the principle is truly staggering, and you know,
Speaker 3: it leaves us with a final, broader concept to mull over.
Speaker 2: What's that?
Speaker 3: The uncertainty principle, at its core is a beautiful lesson
Speaker 3: in humility from nature. It proves mathematically that the more
Speaker 3: aggressively we try to isolate and control one specific aspect
Speaker 3: of a complex system, the more a complementary aspect slips
Speaker 3: entirely out of our grasp. Oh wow, yeah, I think
Speaker 3: that invites us to look beyond physics. In our pursuit
Speaker 3: of knowledge, we often operate under the assumption that absolute
Speaker 3: microscopic precision is the ultimate goal. But perhaps the deepest
Speaker 3: truths don't emerge from achieving perfect control.
Speaker 2: They come from the blur exactly.
Speaker 3: Perhaps they come from recognizing and actually embracing where precision
Speaker 3: must end. The quantum realm asks us to accept a
Speaker 3: baseline level of inherent fuzziness in exchange for a much
Speaker 3: richer dynamic reality.
Speaker 2: Embracing the fuzziness. I love that, because trying to perfectly
Speaker 2: pin down reality really is a fool's errand the tighter
Speaker 2: your grip, the more reality just slips away. Keep your
Speaker 2: curiosity alive, embrace the uncertainty, and we will catch you
Speaker 2: next time.