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Is Quantum Randomness Real? A New Challenge to the Foundations of Physics · 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: You know, when you really stop and just look at
• 0:30
  Speaker 2: the physical world around you, like the classical everyday macroscopic world,
• 0:35
  Speaker 2: things basically just make intuitive sense. Right.
• 0:38
  Speaker 3: It's predictable.
• 0:39
  Speaker 2: Exactly. There's this rigid predictability to everything that feels, I
• 0:42
  Speaker 2: don't know, very comforting. Like you throw a baseball, and
• 0:45
  Speaker 2: if you know its mass, the velocity of your arm, gravity,
• 0:48
  Speaker 2: wind resistance.
• 0:49
  Speaker 3: You can calculate the exact arc.
• 0:51
  Speaker 2: Yeah, exactly the arc. It'll land precisely where the math
• 0:53
  Speaker 2: says it should land. And from Isaac Newton to, you know,
• 0:57
  Speaker 2: Pierre Simon Laplace, physics was basically built on this whole
• 1:00
  Speaker 2: idea of a clockwork universe.
• 1:02
  Speaker 3: A very neat, orderly machine.
• 1:05
  Speaker 2: Right. But the moment you zoom in, right, when you
• 1:09
  Speaker 2: step down into the subatomic quantum world, that comforting clockwork
• 1:13
  Speaker 2: just completely shatters.
• 1:15
  Speaker 3: It falls apart entirely.
• 1:16
  Speaker 2: It really does. You're suddenly dealing with this reality check
• 1:19
  Speaker 2: that genuinely breaks classical logic. In quantum mechanics... the state
• 1:24
  Speaker 2: of a system changes smoothly and predictably, kind of like
• 1:27
  Speaker 2: that baseball, but with one massive, terrifying catch.
• 1:31
  Speaker 4: Which is that nobody can be looking at it.
• 1:33
  Speaker 2: Right. It only behaves predictably so long as nobody is
• 1:37
  Speaker 2: actually measuring it.
• 1:38
  Speaker 4: It is arguably the ultimate paradox of modern physics. It's
• 1:42
  Speaker 4: usually referred to as the measurement problem.
• 1:44
  Speaker 2: The measurement problem, yeah.
• 1:45
  Speaker 4: Because if you look at the fundamental equation of quantum mechanics,
• 1:49
  Speaker 4: the Schrodinger equation, it describes a system evolving as this...
• 1:53
  Speaker 4: This wave of spreading potentialities.
• 1:56
  Speaker 2: Like a wave of possibilities. Exactly.
• 1:58
  Speaker 4: Mathematically, it's called unitary evolution, and it's entirely deterministic. But
• 2:03
  Speaker 4: the exact moment a quantum system is measured or observed.
• 2:07
  Speaker 2: It just snaps, right? Yes.
• 2:08
  Speaker 4: That smooth, predictable evolution vanishes. The wave function collapses. The
• 2:12
  Speaker 4: system abruptly snaps into a single, definite state. And the
• 2:17
  Speaker 4: result appears to be decided entirely at random.
• 2:19
  Speaker 2: Which is just, I mean, it's a complete violation of
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  Speaker 2: cause and effect as we actually experience it.
• 2:24
  Speaker 3: It really is.
• 2:25
  Speaker 2: Look at it this way. Imagine you have a coin
• 2:27
  Speaker 2: spinning on a table, right? In our everyday reality, we
• 2:30
  Speaker 2: know the coin is just a physical disk of metal
• 2:32
  Speaker 2: rotating at a specific speed. Sure. If our eyes were
• 2:35
  Speaker 2: fast enough, we could literally track it. We'd know if
• 2:39
  Speaker 2: it was heads or tails at any given microsecond. But
• 2:42
  Speaker 2: in the quantum world, it's not just moving fast. It
• 2:45
  Speaker 2: exists in a superposition. Right.
• 2:47
  Speaker 3: It's mathematically, it's neither heads nor tails.
• 2:50
  Speaker 2: Exactly. It's in this weird state of suspended animakin. And
• 2:54
  Speaker 2: it somehow abruptly commits to a final state only at
• 2:57
  Speaker 2: the exact millisecond you interact with it.
• 3:00
  Speaker 4: The transition from a deterministic wave to a random single
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  Speaker 4: outcome is just jarring. And what's really critical for you
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  Speaker 4: to understand here is just how much that abrupt commitment
• 3:11
  Speaker 4: has tormented the scientific community.
• 3:13
  Speaker 3: Since like the 1920s.
• 3:15
  Speaker 2: Tormented is a good word for it.
• 3:16
  Speaker 3: It has.
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  Speaker 4: Because the Schrodinger equation doesn't actually tell you which outcome
• 3:22
  Speaker 4: will happen. It only gives you the wave function. Okay.
• 3:26
  Speaker 4: To actually predict anything in a laboratory, physicists have to
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  Speaker 4: use an entirely separate mathematical tool called the Born Rule.
• 3:34
  Speaker 2: And we should really unpack this Born Rule because it
• 3:36
  Speaker 2: seems to be the center of this entire century-old headache
• 3:39
  Speaker 2: we're exploring today.
• 3:40
  Speaker 3: It absolutely is.
• 3:42
  Speaker 2: We're really going to get into how physicists have historically
• 3:44
  Speaker 2: relied on this cheat code, the Born Rule, to calculate
• 3:48
  Speaker 2: the chances of these random quantum outcomes.
• 3:51
  Speaker 4: Right.
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  Speaker 2: And more importantly, why recent pretty groundbreaking research from Jiaxuan
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  Speaker 2: Zhang at the University of Oxford suggests that the physicists
• 4:00
  Speaker 2: trying to explain this randomness might be accidentally cheating their
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  Speaker 2: own math.
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  Speaker 4: The stakes here for our fundamental understanding of reality are
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  Speaker 4: incredibly high. I bet. To understand Zhang's breakthrough, we first
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  Speaker 4: have to understand why the Born rule is treated with
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  Speaker 4: such suspicion in the first place.
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  Speaker 2: Okay, lay it out for me.
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  Speaker 4: Well, the framework of quantum theory operates on strict, non-random
• 4:22
  Speaker 4: mathematical structures, like vectors rotating in a multidimensional mathematical arena
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  Speaker 4: called Hilbert space.
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  Speaker 2: Sounds very precise.
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  Speaker 3: Highly precise.
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  Speaker 4: But the Born rule is an ad hoc postulate. It
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  Speaker 4: states that the probability of finding a system in a
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  Speaker 4: particular state is equal to the square of the amplitude
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  Speaker 4: of its wave function.
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  Speaker 2: Okay.
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  Speaker 4: The key takeaway is that it is literally the only
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  Speaker 4: place where probability enters quantum theory.
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  Speaker 2: Wait, hold on. So the Born rule isn't even derived
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  Speaker 2: from the Schrödinger equation. No. They just slapped it on
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  Speaker 2: top of the theory because they needed the math to
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  Speaker 2: match what they were actually seeing in the lab.
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  Speaker 3: That's, yes.
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  Speaker 4: Max Born proposed it in 1926, and you're exactly right.
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  Speaker 4: It was essentially an empirical patch.
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  Speaker 2: Wow.
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  Speaker 4: The deterministic math of quantum mechanics doesn't naturally produce probabilities.
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  Speaker 4: So Born introduced a rule that translates the wave function
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  Speaker 4: into odds.
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  Speaker 2: That feels like a massive leap. It is.
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  Speaker 4: And because of this incredibly awkward contrast where you have
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  Speaker 4: this beautiful non-random machinery suddenly relying on an unexplainable probability
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  Speaker 4: generator at the very end, physicists have spent decades trying
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  Speaker 4: to sort of derive the Born rule from the theory's
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  Speaker 4: other unitary rules.
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  Speaker 2: I'm stuck on this point, though. I mean, if the
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  Speaker 2: Born rule is the only random part and it works
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  Speaker 2: perfectly in actual experiments, why don't physicists just accept it?
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  Speaker 3: That's the big question.
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  Speaker 2: Like, why spend 100 years trying to mathematically prove that
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  Speaker 2: the universe isn't actually rolling dice? Is it just mathematical
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  Speaker 2: aesthetics or?
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  Speaker 4: Oh, it goes much deeper than aesthetics. It's really about
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  Speaker 4: the fundamental nature of the universe.
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  Speaker 2: Okay.
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  Speaker 3: See, if the.
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  Speaker 4: Born rule is just a brute fact, then true uncaused
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  Speaker 4: randomness is the actual bedrock of reality.
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  Speaker 2: Which is terrifying for a physicist.
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  Speaker 3: Exactly.
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  Speaker 4: But if scientists can successfully derive the Born rule from
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  Speaker 4: the foundational non-random parts of quantum theory, it would prove
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  Speaker 4: that what we perceive as quantum randomness actually emerges from
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  Speaker 4: a deeper, entirely predictable cause.
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  Speaker 2: Ah. So it would mean there's an underlying deterministic mechanism
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  Speaker 2: we just couldn't see before. Exactly. So they basically want
• 6:35
  Speaker 2: to rescue the clockwork universe.
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  Speaker 4: Yes.
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  Speaker 2: They want to prove that the wave function doesn't actually
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  Speaker 2: roll dice, but that the structure of the math itself
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  Speaker 2: logically forces the outcome to just look probabilistic to us.
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  Speaker 3: That is exactly the goal.
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  Speaker 4: And I mean, over the decades, brilliant physicists have proposed
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  Speaker 4: all sorts of various ways to do this. You have
• 6:55
  Speaker 4: Andrew Gleason's famous theorem from 1957, which which attempted to
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  Speaker 4: show that the Born rule is the only logically consistent
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  Speaker 4: way to assign probabilities to quantum states.
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  Speaker 2: Okay.
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  Speaker 4: You also have the many worlds interpretation pioneered.
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  Speaker 3: By Hugh Everett.
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  Speaker 2: Like the multiverse stuff?
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  Speaker 4: Yes. Suggesting the universe branches into multiple realities. And later
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  Speaker 4: physicists tried to derive the Born rule by calculating the
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  Speaker 4: quote unquote weight of these different branches.
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  Speaker 2: Wow.
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  Speaker 4: Okay. And more recently, there are decision theoretic approaches. That's
• 7:23
  Speaker 4: where theorists try to prove that a rational agent betting
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  Speaker 4: on quantum outcomes would naturally adopt the Born rule.
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  Speaker 2: But the problem with all these historical attempts, if I'm
• 7:31
  Speaker 2: understanding this right, is that they don't even speak the
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  Speaker 2: same language.
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  Speaker 3: They really don't.
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  Speaker 2: Like you have Gleason using pure geometry. You have Everettian
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  Speaker 2: physicists using branching universes. And decision theorists talking about the
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  Speaker 2: logic of gambling agents.
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  Speaker 4: Right.
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  Speaker 2: If I'm a theoretical physicist trying to evaluate these claims,
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  Speaker 2: I can't exactly put them side by side on a chalkboard.
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  Speaker 4: No, and that incompatibility is a massive roadblock. Every single
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  Speaker 4: one of these derivations requires its own specific set of
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  Speaker 4: starting assumptions.
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  Speaker 2: Makes sense.
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  Speaker 4: And when you're trying to prove the origin of probability,
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  Speaker 4: the hardest thing for a scientist to do is to
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  Speaker 4: forget what they already know to be true.
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  Speaker 2: Because they already know it works in the lab.
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  Speaker 1: Right.
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  Speaker 4: We know measurements yield probabilities in the real world, so
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  Speaker 4: it's remarkably easy to accidentally bake that probabilistic knowledge into
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  Speaker 4: your starting assumptions without even realizing it.
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  Speaker 2: Which means you end up Accidentally assuming the very answer
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  Speaker 2: you're trying to prove.
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  Speaker 3: Exactly.
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  Speaker 2: And this is where Joshua and Zhang's work comes in.
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  Speaker 2: Because instead of trying to add yet another derivation to
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  Speaker 2: this giant pile, she basically played auditor, right?
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  Speaker 4: She did. She rigorously dissected the most prominent historical models.
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  Speaker 2: But to do that without bias, she had to completely
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  Speaker 2: wipe the slate clean. Like she had to strip away
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  Speaker 2: the concept of probability entirely?
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  Speaker 4: Yes. Her methodology is brilliant specifically because of its austerity.
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  Speaker 4: She intentionally refused to assume that measurements involve probabilities or
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  Speaker 4: likelihoods or chances of any kind.
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  Speaker 2: So no probability at all? None.
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  Speaker 4: Instead, she took the mathematical structure of quantum mechanics, those
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  Speaker 4: state vectors and Hilbert space we mentioned, and simply assigned
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  Speaker 4: a generic mathematical function, just a neutral number, to each
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  Speaker 4: possible measurement outcome.
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  Speaker 2: Okay, let me make sure I'm following the mathematical translation here.
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  Speaker 2: In quantum mechanics, a state vector is basically an arrow
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  Speaker 2: pointing in a high dimensional space, right? And it describes
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  Speaker 2: all the info about the system.
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  Speaker 3: Yes, that's a good way to picture it.
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  Speaker 2: And usually physicists use the Born rule to calculate the
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  Speaker 2: length of that arrow's shadow along a certain axis, square it,
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  Speaker 2: and literally call it probability. Right. But Zhang is saying,
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  Speaker 2: let's not call it probability. Let's just apply a generic function,
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  Speaker 2: let's call it f, and assign it to the state.
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  Speaker 2: No meaning attached at all.
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  Speaker 3: That is the exact mechanism.
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  Speaker 4: And by tracking this neutral function f, she could coldly
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  Speaker 4: trace the logical steps of five major historical derivations, including
• 9:55
  Speaker 4: Gleason's theorem and the Everettian approaches.
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  Speaker 2: Like watching a mad trick in extreme slow motion.
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  Speaker 3: Huh, yes.
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  Speaker 2: Ignoring the magician's distracting patter and just focusing on the
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  Speaker 2: mechanics of where the rabbit is actually coming from?
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  Speaker 3: That's exactly it.
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  Speaker 4: She stripped the specific language and the physical interpretations away
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  Speaker 4: from all of them. reduced them to their bare mathematical metal,
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  Speaker 4: and just looked at the rules they were applying to
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  Speaker 4: this generic function f.
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  Speaker 2: Okay, so we really have to look at the rules
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  Speaker 2: these previous physicists applied to their math to see if
• 10:28
  Speaker 2: they were smuggling probability in. Right. And Zhang focused on
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  Speaker 2: two major assumptions that historical derivations often kind of blurred together.
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  Speaker 2: So let's define the first one, which is additivity.
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  Speaker 3: Yes, additivity is foundational here.
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  Speaker 4: In the context of quantum state vectors, Additivity dictates how
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  Speaker 4: we handle orthogonal states.
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  Speaker 2: Orthogonal meaning what, exactly?
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  Speaker 4: Oh, mutually exclusive outcomes. For example, measuring an electron's spin
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  Speaker 4: and finding its unequivocally spin up versus unequivocally spin down.
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  Speaker 2: Okay. Mutually exclusive.
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  Speaker 4: Right. Additivity assumes that if you want to assign a
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  Speaker 4: value to the combination of these mutually exclusive states, you
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  Speaker 4: simply add their individual values together.
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  Speaker 2: Like basic addition? Yes.
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  Speaker 4: So the function f of state A plus state B
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  Speaker 4: is assumed to equal f of A plus f of B.
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  Speaker 2: Okay. I'm struggling to see how that implies anything controversial, though. Like,
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  Speaker 2: if things are completely separate and mutually exclusive, adding them
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  Speaker 2: together just seems like basic common sense.
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  Speaker 4: Well, it is common sense in a classical universe, but
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  Speaker 4: quantum mechanics is defined by interference.
• 11:40
  Speaker 2: Ah, right.
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  Speaker 4: In quantum systems, states don't always just add up like
• 11:44
  Speaker 4: classical objects. their wave amplitudes can interfere constructively or destructively.
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  Speaker 2: So they mess with each other.
• 11:51
  Speaker 3: Exactly.
• 11:52
  Speaker 4: Assuming simple mathematical additivity for measurement outcomes forces a very
• 11:56
  Speaker 4: specific classical structure onto a quantum system.
• 12:00
  Speaker 2: Oh, I see. Okay. Let me try a mechanical analogy
• 12:04
  Speaker 2: to replace the classical intuition here. Imagine you're trying to
• 12:07
  Speaker 2: calculate the volume of liquid by pouring two separate cups
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  Speaker 2: into a larger bowl.
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  Speaker 4: Okay.
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  Speaker 2: In a classical world, The volume of cup A plus
• 12:17
  Speaker 2: the volume of cup B equals the total volume. Simple additivity.
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  Speaker 4: Right.
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  Speaker 2: But a quantum system is more like having quantum cups
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  Speaker 2: of liquid that interact the moment they touch. Like the
• 12:30
  Speaker 2: liquids might chemically react or expand or totally cancel each
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  Speaker 2: other out. So the total volume is completely different than
• 12:38
  Speaker 2: just A plus B.
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  Speaker 4: That analogy captures the restriction perfectly. By demanding additivity... you're
• 12:45
  Speaker 4: demanding that the quantum system behaves logically like a set
• 12:48
  Speaker 4: of distinct classical events. Wow.
• 12:51
  Speaker 2: Okay.
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  Speaker 4: Now, let's pair that with the second major assumption Zong analyzed,
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  Speaker 4: which is known as non-contextuality.
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  Speaker 2: Non-contextuality. Let's define that in terms of the quantum math.
• 13:05
  Speaker 2: If we're still in Hilbert space, measuring state vectors, what
• 13:08
  Speaker 2: does non-contextuality actually assume?
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  Speaker 4: So non-contextuality assumes that the value assigned to a specific
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  Speaker 4: state doesn't depend on the broader context of the measurement setup.
• 13:18
  Speaker 2: Okay.
• 13:19
  Speaker 4: In quantum mechanics, we often rely on frameworks like the
• 13:22
  Speaker 4: Koken-Specker theorem, which deals with how different observable properties commute
• 13:26
  Speaker 4: or basically share the same measurement basis.
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  Speaker 2: I'm with you.
• 13:30
  Speaker 4: Non-contextuality essentially says that if I measure property A alongside
• 13:34
  Speaker 4: property B, the intrinsic value of property A is exactly
• 13:37
  Speaker 4: the same as it would be if I had chosen
• 13:39
  Speaker 4: to measure property A alongside a completely different property, C.
• 13:43
  Speaker 2: Wait, hold on. If we know that the very act
• 13:45
  Speaker 2: of measurement actively collapses the wave function and forces the
• 13:49
  Speaker 2: system into a definite state, wouldn't the specific way we
• 13:52
  Speaker 2: measure it inherently matter?
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  Speaker 4: You've hit on exactly why non-contextuality is such a strong assumption.
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  Speaker 4: The idea that a quantum state possesses an intrinsic value
• 14:02
  Speaker 4: independent of the experimental context is highly debated.
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  Speaker 2: I can see why.
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  Speaker 4: But for decades, theoretical physicists often just mushed additivity and
• 14:10
  Speaker 4: noncontextuality together in their derivations. They treated them as a single, inevitable,
• 14:15
  Speaker 4: logical step.
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  Speaker 2: So Zhang separates these two concepts. She takes her neutral
• 14:20
  Speaker 2: mathematical function, applies the strict definitions of additivity and noncontextuality,
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  Speaker 2: And then runs this diagnostic through the five historical derivations.
• 14:29
  Speaker 4: Yes.
• 14:30
  Speaker 2: What exactly does she find in the gears of the math?
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  Speaker 4: She finds a fundamental flaw. When she isolates the mechanics
• 14:37
  Speaker 4: of these historical arguments from the geometric proofs of Gleason
• 14:41
  Speaker 4: to the rational betting agents in the many worlds theory,
• 14:45
  Speaker 4: she discovers that all five derivations absolutely require additivity to function.
• 14:50
  Speaker 2: Wait, all of them? Even though they were built on
• 14:53
  Speaker 2: entirely different philosophical foundations?
• 14:55
  Speaker 3: Even then.
• 14:56
  Speaker 4: Sometimes the requirement is stated openly, like in Gleason's theorem,
• 15:00
  Speaker 4: which explicitly requires a non-negative additive function. But in other derivations,
• 15:05
  Speaker 4: it's buried really deep within the logic.
• 15:08
  Speaker 2: How deep are we talking?
• 15:09
  Speaker 4: Well, for example, in the decision-theoretic approaches, where physicists imagine
• 15:13
  Speaker 4: a rational agent making bets on quantum branches, the very
• 15:17
  Speaker 4: rules used to define what makes a bet rational secretly
• 15:21
  Speaker 4: smuggle in the requirement for additivity. And in another derivation
• 15:26
  Speaker 4: she analyzed, the mathematical argument completely collapsed until additivity was
• 15:31
  Speaker 4: artificially injected into it after the fact.
• 15:33
  Speaker 2: This is the massive aha moment of the research. Because
• 15:37
  Speaker 2: the reason this matters, the reason Zhang's audit is so
• 15:41
  Speaker 2: devastating to these historical attempts, is because of what additivity
• 15:45
  Speaker 2: mathematically represents.
• 15:46
  Speaker 3: Yes, exactly.
• 15:48
  Speaker 2: If you go back to the foundational axioms of classical probability,
• 15:51
  Speaker 2: which were laid out by Andrei Kolmogorov in like the 1930s.
• 15:56
  Speaker 2: His entire mathematical definition of probability relies on the additivity
• 16:00
  Speaker 2: of mutually exclusive events.
• 16:02
  Speaker 4: The connection to Kolmogorov is exactly the point. The axioms
• 16:05
  Speaker 4: of classical probability are built on the rule that the
• 16:08
  Speaker 4: probability of one mutually exclusive event or another occurring is
• 16:12
  Speaker 4: simply the sum of their individual probabilities.
• 16:14
  Speaker 2: Right. It's identical.
• 16:16
  Speaker 4: Additivity is not just a neutral mathematical operation. It is
• 16:19
  Speaker 4: the defining signature of classical probability.
• 16:22
  Speaker 2: So let me get this straight. These physicists who spent
• 16:25
  Speaker 2: decades trying to derive quantum probability from pure deterministic mathematics
• 16:31
  Speaker 2: didn't actually do it.
• 16:32
  Speaker 3: No, they didn't.
• 16:34
  Speaker 2: They wanted to prove that randomness emerges naturally from a
• 16:37
  Speaker 2: non-random theory. But by requiring additivity to make their equations balance...
• 16:42
  Speaker 2: They were subtly injecting the very axioms of classical probability
• 16:46
  Speaker 2: into the math from the very first step.
• 16:49
  Speaker 3: They absolutely were.
• 16:50
  Speaker 4: If you assume additivity, you are inherently assuming a probability-like structure.
• 16:55
  Speaker 2: That's wild.
• 16:56
  Speaker 4: You cannot extract quantum probabilities from a theory that contains
• 17:00
  Speaker 4: no probability to begin with if the only way you
• 17:02
  Speaker 4: can finish the math is by utilizing the mathematical definition
• 17:05
  Speaker 4: of probability. The classical bias was basically baked into the
• 17:09
  Speaker 4: equations all along.
• 17:10
  Speaker 2: It's mathematically circular.
• 17:11
  Speaker 4: Yes.
• 17:12
  Speaker 2: They were trying to prove where probability comes from, but
• 17:15
  Speaker 2: their proofs only worked because they implicitly assumed probability already existed.
• 17:19
  Speaker 3: Exactly.
• 17:20
  Speaker 2: That really forces us to realize that our desire for
• 17:24
  Speaker 2: a deterministic universe might just be a classical bias that
• 17:27
  Speaker 2: we are stubbornly projecting onto the quantum world.
• 17:31
  Speaker 4: It is a really profound realization about how theoretical physics operates. Now,
• 17:35
  Speaker 4: to be clear... Zhang's audit doesn't claim that a probability-free
• 17:40
  Speaker 4: derivation of the Born rule is unequivocally impossible forever.
• 17:44
  Speaker 2: Right. Science is always open.
• 17:46
  Speaker 4: But her rigorous diagnostic proves that without some extra probability-like assumption,
• 17:52
  Speaker 4: the math simply doesn't arrive at the Born rule.
• 17:55
  Speaker 2: So what does this mean for the theoretical physics community
• 17:58
  Speaker 2: moving forward? Does this effectively act as a sort of,
• 18:02
  Speaker 2: I don't know, a BS detector for any future claims
• 18:05
  Speaker 2: about the measurement problem?
• 18:06
  Speaker 4: It serves as an incredibly powerful diagnostic tool. Before Zhang's work,
• 18:11
  Speaker 4: if a physicist published a paper claiming to have finally
• 18:14
  Speaker 4: derived the Born rule from pure determinism, verifying the claim
• 18:18
  Speaker 4: was a tangled mess of conflicting assumptions.
• 18:21
  Speaker 2: Because you couldn't compare apples to oranges. Exactly.
• 18:25
  Speaker 4: But now the community has a formalized methodology. They can
• 18:28
  Speaker 4: look at the new derivation, map the logic, and pinpoint
• 18:31
  Speaker 4: the exact moment an additivity assumption is smuggled in.
• 18:33
  Speaker 1: Wow.
• 18:34
  Speaker 4: It forces a new standard of radical transparency regarding starting axioms.
• 18:39
  Speaker 2: It also forces the scientific community to confront a deeply
• 18:42
  Speaker 2: unsettling philosophical question, doesn't it?
• 18:45
  Speaker 3: It really does.
• 18:45
  Speaker 2: Because for nearly a century, scientists have desperately wanted to
• 18:49
  Speaker 2: believe that the universe is orderly at its core, that
• 18:53
  Speaker 2: quantum randomness is just a gap in our understanding. like
• 18:56
  Speaker 2: a temporary veil hiding deeper, predictable principles.
• 19:00
  Speaker 4: It challenges the very classical intuition we open this conversation with.
• 19:03
  Speaker 4: We want the universe to be calculable. We want to
• 19:06
  Speaker 4: know where the baseball's going to land.
• 19:08
  Speaker 2: We need to know where it lands.
• 19:09
  Speaker 3: We do.
• 19:11
  Speaker 4: But the mathematical reality, when audited strictly without our classical biases,
• 19:15
  Speaker 4: strongly suggests that the randomness isn't just a bug in
• 19:18
  Speaker 4: our equations. It might be an inescapable feature of the universe.
• 19:22
  Speaker 2: Which leaves you with a truly heavy thought to chew on. Because, look,
• 19:27
  Speaker 2: if probability and randomness genuinely cannot be mathematically derived from
• 19:32
  Speaker 2: deeper deterministic rules, if physicists are continually forced to assume
• 19:37
  Speaker 2: a probabilistic structure as a foundational starting point just to
• 19:41
  Speaker 2: make the math work, does that mean true randomness is
• 19:45
  Speaker 2: the actual fundamental bedrock of reality?
• 19:48
  Speaker 3: It requires us to rethink what reality actually is.
• 19:51
  Speaker 2: It really does. Because if the universe fundamentally plays dice
• 19:55
  Speaker 2: at its lowest microscopic levels, it implies that the rigid
• 19:59
  Speaker 2: cause and effect we experience in our daily lives, like
• 20:03
  Speaker 2: the predictability of that thrown baseball, is really just an
• 20:06
  Speaker 2: illusion generated by scale. If the very fabric of reality
• 20:11
  Speaker 2: is built on a foundation of pure chance, maybe that
• 20:14
  Speaker 2: wave function isn't waiting for us to measure it so
• 20:17
  Speaker 2: it can obey classical rules. Maybe in the end, it's
• 20:21
  Speaker 2: the quantum randomness that actually rules us.