Latest / The Quark Side - Quantum Physics Podcast / Did Scientists Create Time in a Laboratory?

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Did Scientists Create Time in a Laboratory? · The Quark Side - Quantum Physics Podcast

• 0:01
  Speaker 1: Welcome to the quart Side Quantum Physics podcast, an exploration
• 0:05
  Speaker 1: of 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 with the smallest scales.
• 0:27
  Speaker 2: Imagine for a second that you take off your watch
• 0:31
  Speaker 2: and you go around your house and hide every single clock. Yeah,
• 0:34
  Speaker 2: you turn off your phone and you pull the blackout
• 0:37
  Speaker 2: curtains tight so you can't see the sun at all.
• 0:39
  Speaker 3: That sounds like a pretty extreme way to spend an afternoon, right.
• 0:43
  Speaker 2: But if you were sitting there in the dark, how
• 0:45
  Speaker 2: would you actually measure the passing of time?
• 0:47
  Speaker 3: Well, I mean you'd probably just feel it, right. We
• 0:49
  Speaker 3: intuitively feel time as this universal, external ticking clock that
• 0:55
  Speaker 3: governs everything in the universe exactly.
• 0:57
  Speaker 2: It is the inescapable background to our entire reality. But
• 1:01
  Speaker 2: what if that intuitive feeling is completely wrong? Like, what
• 1:04
  Speaker 2: if time itself isn't a fundamental, built in feature of
• 1:07
  Speaker 2: the universe.
• 1:08
  Speaker 3: It is a profoundly unsettling reality to confront. Honestly, human
• 1:12
  Speaker 3: consciousness is deeply wired to expect a cosmic metronome ticking
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  Speaker 3: away in the background.
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  Speaker 2: Yeah, a relentless progression completely independent of our existence exactly.
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  Speaker 2: But in twenty twenty six, professor Giovanni Barantini at the
• 1:24
  Speaker 2: University of Birmingham published some truly groundbreaking work in Physical
• 1:28
  Speaker 2: Review Research. And his team didn't just theorize.
• 1:31
  Speaker 3: About this, No, they didn't. They successfully built a mini
• 1:35
  Speaker 3: universe in a laboratory.
• 1:37
  Speaker 2: A mini universe that measures the flow of time without using.
• 1:39
  Speaker 3: A clock at all, which is just wild.
• 1:43
  Speaker 2: Okay, let's unpack this. Is time fundamentally real like the
• 1:47
  Speaker 2: concrete foundation of a house, or is it more like
• 1:50
  Speaker 2: the temperature of a room?
• 1:52
  Speaker 3: That is a great way to frame it.
• 1:53
  Speaker 2: Because temperature isn't a physical thing itself, it's just the
• 1:57
  Speaker 2: resulting illusion, you know, the emergent property of a bunch
• 2:01
  Speaker 2: of atoms moving around.
• 2:02
  Speaker 3: And that debate over emergence versus fundamental reality has kept
• 2:06
  Speaker 3: physicists awake at night for almost a century. I bet,
• 2:09
  Speaker 3: but Barantini's experiment provides actual physical, empirical evidence leaning heavily
• 2:15
  Speaker 3: toward your second option.
• 2:16
  Speaker 2: That time is an emergent property, right.
• 2:18
  Speaker 3: A macroscopic illusion born from microscopic mechanics.
• 2:22
  Speaker 2: We are going to explore exactly how scientists trapped quantum
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  Speaker 2: atoms to create this clockless cosmos, how time can actually
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  Speaker 2: stop inside of it, and well what this fundamentally means
• 2:33
  Speaker 2: for our understanding of reality.
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  Speaker 3: It's a huge shift in how we see everything.
• 2:37
  Speaker 2: But if you want to prove time isn't real, you
• 2:38
  Speaker 2: can't just do it on a chalkboard, right. You have
• 2:41
  Speaker 2: to physically step outside the timeline of the universe.
• 2:43
  Speaker 3: To test it, which is obviously a bit of a problem, right.
• 2:47
  Speaker 2: Since we obviously can't leave the universe. Barantini had to
• 2:50
  Speaker 2: build a loophole, a pocket dimension on a lab bench.
• 2:53
  Speaker 3: And to understand the necessity of that massive engineering challenge,
• 2:56
  Speaker 3: we have to look at the theoretical clash that force
• 2:59
  Speaker 3: their hands in the first.
• 3:00
  Speaker 2: Place, the quantum time problem.
• 3:02
  Speaker 3: Yeah, in our everyday macroscopic lives, time very clearly flows
• 3:07
  Speaker 3: in one direction, from the past to the future.
• 3:10
  Speaker 2: You drop a coffee mug, it shatters exactly.
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  Speaker 3: The shards never spontaneously reassemble themselves and jump back up
• 3:16
  Speaker 3: onto the table.
• 3:17
  Speaker 2: That's the classic arrow of time driven by thermodynamics.
• 3:20
  Speaker 3: But when you zoom down to the foundational microscopic level,
• 3:24
  Speaker 3: the realm of particles and wave functions and quantum mechanics,
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  Speaker 3: that arrow just.
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  Speaker 2: Vanishes, It completely disappears.
• 3:32
  Speaker 3: Yeah, the basic equations of physics are time symmetric. They
• 3:35
  Speaker 3: work exactly the same forward and backward. The fundamental math
• 3:39
  Speaker 3: doesn't care which direction the film is running.
• 3:41
  Speaker 2: That structural paradox gets pushed to its absolute limit when
• 3:45
  Speaker 2: we look at the wheelir to Wit equations. Oh, absolutely,
• 3:48
  Speaker 2: Because if you are trying to reconcile quantum mechanics with
• 3:52
  Speaker 2: general relativity to actually build a working model of quantum gravity.
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  Speaker 3: The math does something terrifying.
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  Speaker 2: It drops the variable of time time entirely.
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  Speaker 3: It does. In the nineteen sixties, John Wheeler and Bryce
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  Speaker 3: de Witt attempted to write down an equation for the
• 4:07
  Speaker 3: quantum state of the.
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  Speaker 2: Entire universe, which is no small task.
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  Speaker 3: Not at all. But general relativity says time is dynamic
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  Speaker 3: and woven into the fabric of space, while quantum mechanics
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  Speaker 3: says time is an absolute, ticking background clock against which
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  Speaker 3: things happen.
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  Speaker 2: So they totally contradict each other exactly.
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  Speaker 3: When you try to merge those two incompatible frameworks mathematically,
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  Speaker 3: time just cancels out.
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  Speaker 2: Wow.
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  Speaker 3: The Wheeler DeWit equation essentially states that at the deepest
• 4:33
  Speaker 3: quantum level, the universe has no built in time. It
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  Speaker 3: exists as a single, static, unchanging quantum state.
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  Speaker 2: Wait, I have to push back on this on behalf
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  Speaker 2: of anyone listening right now.
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  Speaker 3: Go for it.
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  Speaker 2: If the mathematical reality of the universe is a static,
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  Speaker 2: completely frozen wave function without a clock.
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  Speaker 3: Why am I aging a very fair question?
• 4:54
  Speaker 2: Why does my coffee still get cold on the desk?
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  Speaker 2: We clearly experience a relentless, one way progression of reality
• 5:01
  Speaker 2: every single day. If the math says the universe is frozen, well,
• 5:06
  Speaker 2: the math feels wrong.
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  Speaker 3: If we connect this to the bigger picture, That exact
• 5:10
  Speaker 3: contradiction is the central problem of quantum gravity.
• 5:13
  Speaker 2: How to get a dynamic reality out of a frozen equation?
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  Speaker 3: Exactly? How do you get a changing reality out of
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  Speaker 3: a fundamentally static, timeless equation. In the nineteen eighties, theorists
• 5:23
  Speaker 3: like Don Page and William Waters proposed a mathematical workaround.
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  Speaker 2: Okay, what was their idea?
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  Speaker 3: They suggested that the universe is static globally, but if
• 5:31
  Speaker 3: you split it into subsystems, say one part acting as
• 5:34
  Speaker 3: an observer and another acting as the observed, then they
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  Speaker 3: can become quantumly entangled. Ah entanglement right, And because of
• 5:41
  Speaker 3: that entanglement, the observer sees the other part changing relative
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  Speaker 3: to itself.
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  Speaker 2: So the sense of time emerges purely from internal relationships
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  Speaker 2: between parts of the universe.
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  Speaker 3: Yes, not from a global ticking clock.
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  Speaker 2: So I mean, instead of a universal timeline, time is
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  Speaker 2: just to localize internal mapping of one thing changing against another.
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  Speaker 3: That was the mathematical theory anyway, but for forty years
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  Speaker 3: it was practically impossible to test.
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  Speaker 2: Because how do you isolate something from the entire universe's
• 6:07
  Speaker 2: timeline exactly?
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  Speaker 3: Baranteini wanted to take this out of the realm of
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  Speaker 3: pure math and see if he could recreate these exact
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  Speaker 3: timeless quantum conditions physically.
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  Speaker 2: He needed an isolated system that actually followed the rules
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  Speaker 2: of Wheeler.
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  Speaker 3: DeWitt, and doing that requires staggering physical engineering.
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  Speaker 2: No kidding. The team at the University of Birmingham started
• 6:27
  Speaker 2: with a cloud of twenty four thousand rubidium atoms. But
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  Speaker 2: you can't just use room temperature atoms, right.
• 6:33
  Speaker 3: No, Because they interact with the environment, they suffer from decoherence.
• 6:37
  Speaker 2: So to make them act as a pristine, isolated quantum universe,
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  Speaker 2: they had to cool them.
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  Speaker 3: Down to a few billionths of a degree above absolute zero.
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  Speaker 2: Which is just incomprehensibly cold.
• 6:48
  Speaker 3: It really is. Removing that thermal noise is crucial. At
• 6:52
  Speaker 3: that ultra coal temperature, you completely eliminate the classical kinetic energy.
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  Speaker 2: So the atoms stop behaving like tiny distinct billiard balls.
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  Speaker 3: Right, and they condense into overlapping waves of probability. It
• 7:03
  Speaker 3: becomes a highly degenerate gas where quantum mechanics dominates entirely.
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  Speaker 2: And then this cloud was placed inside a hermetically sealed
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  Speaker 2: optical environment.
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  Speaker 3: Completely isolated from any outside environmental interference.
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  Speaker 2: So they successfully built their universe in a bottle, just
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  Speaker 2: the pristine blob of pure quantum potential.
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  Speaker 3: But a static blob doesn't simulate our.
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  Speaker 2: Cosmos, right, it doesn't do anything.
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  Speaker 3: So they used a thin barrier made of two laser
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  Speaker 3: beams operating at different frequencies to split this quantum cloud
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  Speaker 3: right down the middle, and.
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  Speaker 2: That laser barrier created an optical dipole trap, effectively carving
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  Speaker 2: the gas into two distinct regions.
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  Speaker 3: An observed region which they called the bright sector okay,
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  Speaker 3: and an unobserved region, the dark sector.
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  Speaker 2: Here's where it gets really interesting. Logically, the dark sector
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  Speaker 2: is acting as the reference.
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  Speaker 3: Frame the theoretical observer.
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  Speaker 2: Yes, and the bright sector is the observable universe. And
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  Speaker 2: within this terraria, they manipulated the lasers so that the
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  Speaker 2: bright region repeatedly expanded and then collapsed in on itself.
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  Speaker 3: They engineered a highly controlled dynamic evolution by varying the
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  Speaker 3: trapping frequencies, the bright sector was forced through a cycle
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  Speaker 3: of expansion and contraction.
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  Speaker 2: So it's functionally simulating a cosmological.
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  Speaker 3: Model, a big bang followed by a big crunch, over
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  Speaker 3: and over.
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  Speaker 2: But because this is a completely sealed quantum system running
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  Speaker 2: on the rules of the Wheeler DeWit equation, there is
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  Speaker 2: no external clock timing this cosmic expansion at all. The
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  Speaker 2: laboratory clock on the wall has absolutely no bearing on
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  Speaker 2: the quantum states inside the bottle.
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  Speaker 3: And this is the genius of the experimental design. The
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  Speaker 3: researchers demonstrated that the sequence of events inside the bright
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  Speaker 3: sector could be perfectly reconstructed from within this.
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  Speaker 2: Mini universe without ever checking the clock in the lab.
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  Speaker 3: Right, the system generated its own internal timeline.
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  Speaker 2: Which leads us to the mechanism of the breakthrough itself.
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  Speaker 2: How do you measure the passage of time without a
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  Speaker 2: temporal variable.
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  Speaker 3: You look at the distribution of the atoms, the entropy.
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  Speaker 2: Okay, entropy is the metronome exactly.
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  Speaker 3: But in this context we aren't just talking about generic
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  Speaker 3: thermodynamic disorder. We are looking at the specific entanglement entropy
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  Speaker 3: between the two sectors.
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  Speaker 2: Because even though the system was isolated from the outside world,
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  Speaker 2: atoms and information could still tunnel or interact across that
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  Speaker 2: laser barrier between the bright and dark regions. Yes, so
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  Speaker 2: instead of a mechanical metronome, the flow of time is
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  Speaker 2: created purely by tracking how the atomic distribution shifted across
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  Speaker 2: that barrier.
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  Speaker 3: It's a brilliant way to measure it.
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  Speaker 2: To use an analogy, think of a brand new, pristine
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  Speaker 2: deck of cards, perfectly ordered by suit and number.
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  Speaker 3: Okay, I'm picturing it.
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  Speaker 2: If you start shuffling it, you don't need a stopwatch
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  Speaker 2: to know that time has passed. You just need to
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  Speaker 2: look at how thoroughly the cards have mixed. The increasing
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  Speaker 2: entropy of the deck is the clock. The state of
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  Speaker 2: the deck maps the passage of time.
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  Speaker 3: That is an excellent way to visualize it. As the
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  Speaker 3: distribution of the bright sector changed relative to the dark
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  Speaker 3: se the researchers could define a chronological progression.
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  Speaker 2: The changing entropy was the physical manifestation of time passing exactly.
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  Speaker 2: But wait, if time is just entropy moving forward, then
• 10:12
  Speaker 2: logically time should speed up or slow down depending on
• 10:16
  Speaker 2: how fast those atoms are reshuffling.
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  Speaker 3: What's fascinating here is that the physical results showed exactly
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  Speaker 3: that really. Yes, Baranteiny coined the term entropic time to
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  Speaker 3: describe this process, and the data revealed three very specific properties.
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  Speaker 2: Okay, the first one.
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  Speaker 3: First, it flows in one consistent direction, providing that elusive
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  Speaker 3: row of time.
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  Speaker 2: So even when the foundational quantum state has no directional preference,
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  Speaker 2: the flow of entropy gives the subsystem a clear past
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  Speaker 2: in future exactly.
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  Speaker 3: And the second property, it correctly and flawlessly orders events.
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  Speaker 3: Even during the wild expansions and contractions. The simulated big
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  Speaker 3: bangs and big crunches tracking the entropy maintained a perfect
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  Speaker 3: chronological record.
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  Speaker 2: Of what happened, completely independent of the labor ratory time.
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  Speaker 3: Completely independent.
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  Speaker 2: But the third property is the real mind bender. Here,
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  Speaker 2: time is entirely variable based on the physical state of
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  Speaker 2: the atoms.
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  Speaker 3: Yes, if the atoms reshuffled rapidly, across the barrier, the
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  Speaker 3: internal and tropic time of that mini universe moved quickly.
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  Speaker 2: And if the reshuffling slowed down.
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  Speaker 3: Time dragged and critically, when the overall distribution of atoms
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  Speaker 3: hid an equilibrium and stopped changing eight, time effectively stopped
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  Speaker 3: for that system.
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  Speaker 2: Okay, I have to stop you there, because the leap
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  Speaker 2: we're making is massive.
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  Speaker 3: It is a big leap.
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  Speaker 2: We are talking about twenty four thousand rubidium atoms isolated
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  Speaker 2: on an optical bench in Birmingham. Can we really scale
• 11:39
  Speaker 2: that up to galaxies, black holes and the macroscopic reality
• 11:44
  Speaker 2: of my morning commute? And claimed that time is merely
• 11:47
  Speaker 2: a localized illusion everywhere.
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  Speaker 3: It is a fair critique. We cannot say this definitively
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  Speaker 3: proves there is no universal time across the entire macroscopic cosmos.
• 11:56
  Speaker 2: Right.
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  Speaker 3: However, it is an undeniable proof of principle for the
• 11:59
  Speaker 3: relational four formulation of quantum mechanics.
• 12:01
  Speaker 2: So it proves physically that a universe can operate entirely
• 12:04
  Speaker 2: without a fundamental temporal dimension.
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  Speaker 3: Yes, it removes the necessity of an external clock from
• 12:09
  Speaker 3: the laws of physics.
• 12:11
  Speaker 2: Which means we have to rewrite the most famous instruction
• 12:13
  Speaker 2: manual for the microscopic universe, the shrouding your equation.
• 12:17
  Speaker 3: To prove this wasn't just a physical parlor trick, they
• 12:20
  Speaker 3: had to demonstrate that the core mathematics of quantum evolution
• 12:23
  Speaker 3: still worked without standard time.
• 12:25
  Speaker 2: Because the traditional shrewding your equation relies on the variable
• 12:29
  Speaker 2: T to dictate how the probability amplitude of a quantum
• 12:33
  Speaker 2: system evolves.
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  Speaker 3: A differential equation that fundamentally requires a change in time.
• 12:38
  Speaker 2: So how do you calculate a wave functions evolution without it?
• 12:42
  Speaker 3: Utilize the page in Woodters mechanism we discussed earlier. The
• 12:45
  Speaker 3: study demonstrated that you can take the standard shrewding Er
• 12:49
  Speaker 3: equation and mathematically strip out the conventional T.
• 12:52
  Speaker 2: And what do you put in its place?
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  Speaker 3: Instead? You parameterize the evolution of the bright sector using
• 12:58
  Speaker 3: the internal state of the dark sect. You replace TEA
• 13:01
  Speaker 3: with the measure of entanglement entropy.
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  Speaker 2: So what does this all mean?
• 13:05
  Speaker 3: It means the math held up perfectly by using in
• 13:08
  Speaker 3: tropic time, the science has successfully predicted how the bright
• 13:11
  Speaker 3: sector would expand, evolve and collapse.
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  Speaker 2: They modeled a dynamic changing quantum system using a completely static,
• 13:19
  Speaker 2: timeless foundational equation exactly. It's like realizing the conductor of
• 13:24
  Speaker 2: an orchestra isn't actually keeping the beat with a baton.
• 13:27
  Speaker 2: We always thought a cosmic conductor was this external force
• 13:30
  Speaker 2: driving the music of reality forward, right, But this experiment
• 13:34
  Speaker 2: proves the beat naturally emerges from the musicians simply deciding
• 13:38
  Speaker 2: to play their instruments together. The collective relational action of
• 13:41
  Speaker 2: the atoms is the.
• 13:42
  Speaker 3: Beat the universe conducts itself. Yeah, this raises an important question, though.
• 13:48
  Speaker 3: If time emerges purely from the relational entanglement of particles,
• 13:52
  Speaker 3: how do we begin to map the evolution of the
• 13:54
  Speaker 3: early universe.
• 13:55
  Speaker 2: Because for decades theoretical physicists have debated how to apply
• 13:59
  Speaker 2: these abstracts quantum gravity models to observable cosmology.
• 14:03
  Speaker 3: And this experiment bridges that massive gap. We finally have
• 14:07
  Speaker 3: a physical mechanism to explain how a timeless quantum singularity
• 14:11
  Speaker 3: it could have given birth to a dynamic, expanding cosmos
• 14:14
  Speaker 3: with a clear arrow of time.
• 14:16
  Speaker 2: So if we zoom out from this microscopic laboratory scale
• 14:19
  Speaker 2: back to the cosmos, the future applications of this are incredible.
• 14:23
  Speaker 2: We don't just have a new philosophy.
• 14:25
  Speaker 3: No, we have a new tool. We have an entirely
• 14:27
  Speaker 3: new test bed for quantum cosmology.
• 14:30
  Speaker 2: Wow.
• 14:31
  Speaker 3: Researchers can now extend this approach to significantly more complex systems.
• 14:35
  Speaker 3: By tweaking the parameters of these optical traps in atomic interactions,
• 14:39
  Speaker 3: they can essentially simulate the thermodynamic and gravitational conditions of
• 14:44
  Speaker 3: black holes directly on a lab bench.
• 14:46
  Speaker 2: Because if the flow of time near a black holes
• 14:48
  Speaker 2: of vent horizon is heavily discorded by gravity, you could
• 14:52
  Speaker 2: theoretically simulate that distortion just by manipulating the entropic variables
• 14:56
  Speaker 2: of the trapped atoms.
• 14:57
  Speaker 3: Exactly, you can test competing theory about how time first
• 15:01
  Speaker 3: emerged from the primordial quantum soup fractions of a second
• 15:04
  Speaker 3: after the Big Bang.
• 15:05
  Speaker 2: Instead of solely relying on computational models or looking at
• 15:09
  Speaker 2: ancient light through telescopes.
• 15:10
  Speaker 3: Physicists can literally poke and prod at the fundamental mechanics
• 15:14
  Speaker 3: of cosmic evolution right here on Earth.
• 15:16
  Speaker 2: That is amazing. You know, the next time you feel
• 15:19
  Speaker 2: like you're running out of time, maybe you're late for
• 15:21
  Speaker 2: a flight or stressing over a deadline.
• 15:23
  Speaker 3: At work, which happens to all of us, right.
• 15:26
  Speaker 2: Just remember that at the foundational quantum level. The ticking
• 15:30
  Speaker 2: clock causing your anxiety might just be an illusion.
• 15:34
  Speaker 3: It is entirely possible that time is not a relentless
• 15:37
  Speaker 3: cosmic river sweeping you forward, but just a localized byproduct
• 15:41
  Speaker 3: of matter rearranging.
• 15:42
  Speaker 2: Itself, a natural emergent consequence of atoms shuffling from one
• 15:47
  Speaker 2: state of probability to another.
• 15:48
  Speaker 3: It profoundly changes how you view physical reality. You aren't
• 15:52
  Speaker 3: moving through time. Your reality is simply continuously reshaping.
• 15:56
  Speaker 2: Itself, and the sensation of time passing is merely your
• 15:59
  Speaker 2: consciousness observing and cataloging that continuous reshaping of local entropy exactly,
• 16:05
  Speaker 2: which leaves us with a truly provocative thought to mullover
• 16:08
  Speaker 2: as we wrap up. If time is not an external,
• 16:10
  Speaker 2: universal ticking clock, but merely a localized byproduct of matter
• 16:15
  Speaker 2: rearranging itself to.
• 16:16
  Speaker 3: Increase entropy, what does that mean for human memory?
• 16:19
  Speaker 2: Exactly? When you recall an event from five years ago,
• 16:22
  Speaker 2: a childhood home or a past conversation, are you actually
• 16:26
  Speaker 2: remembering the past in a temporal sense.
• 16:28
  Speaker 3: Or is the concept of the past entirely imaginary?
• 16:31
  Speaker 2: Perhaps our brains are simply recording, mapping, and accessing a
• 16:35
  Speaker 2: lower entropy state of our own internal neurological mini universe