Latest / The Quark Side - Quantum Physics Podcast / The Revolutionary Clock That Runs on the Secrets of Atomic Nuclei

Transcript

The Revolutionary Clock That Runs on the Secrets of Atomic Nuclei · 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: Have you ever actually thought about how we define a second? Like,
• 0:31
  Speaker 2: really define it?
• 0:32
  Speaker 3: I mean, most people probably just think of, you know,
• 0:35
  Speaker 3: counting it out in their head.
• 0:36
  Speaker 2: Right. Like waiting for a traffic light to change. Just
• 0:39
  Speaker 2: one Mississippi, two Mississippi. Exactly. But I'm talking about the
• 0:42
  Speaker 2: absolute fundamental definition that literally runs our entire global society.
• 0:47
  Speaker 2: I mean, your phone, the financial markets, the GPS network
• 0:51
  Speaker 2: guiding airplanes.
• 0:52
  Speaker 3: Yeah, all of that.
• 0:53
  Speaker 2: They are all synchronized to this incredibly precise rhythm. But
• 0:58
  Speaker 2: right now, that rhythm is on the verge of a
• 1:01
  Speaker 2: massive disruption.
• 1:02
  Speaker 3: It really is. It's a huge shift.
• 1:06
  Speaker 2: Because in Vienna right now, a team has officially activated
• 1:10
  Speaker 2: the world's first standalone nuclear clock. And to build it,
• 1:15
  Speaker 2: they had to completely abandon our traditional methods of keeping time.
• 1:19
  Speaker 3: Yeah, they had to stop looking at atoms entirely.
• 1:21
  Speaker 2: Right. And start looking at the microscopic void inside of them. So, okay.
• 1:27
  Speaker 2: Let's unpack this. We want to understand exactly how we
• 1:30
  Speaker 2: are making this crazy jump from traditional atomic timekeeping to, well,
• 1:36
  Speaker 2: nuclear timekeeping.
• 1:37
  Speaker 3: Which is a monumental leap.
• 1:38
  Speaker 2: Absolutely. We need to figure out how this self-stabilizing prototype
• 1:42
  Speaker 2: actually works and why shrinking our timekeepers could completely revolutionize
• 1:47
  Speaker 2: how we understand the physical world.
• 1:49
  Speaker 3: Because it's not just, you know, an incremental update to
• 1:52
  Speaker 3: a piece of lab equipment. We are witnessing a fundamental
• 1:56
  Speaker 3: paradigm shift in physics here.
• 1:57
  Speaker 2: A complete rewrite of the rules.
• 1:59
  Speaker 3: Exactly. For decades, the global gold standard has been the
• 2:02
  Speaker 3: atomic clock. It dictates the pace of modern technology. But
• 2:06
  Speaker 3: moving to a nuclear clock completely rewrites metrology, the science
• 2:09
  Speaker 3: of measurement.
• 2:10
  Speaker 2: So we are changing the underlying mechanism of how humanity
• 2:14
  Speaker 2: measures time itself.
• 2:15
  Speaker 3: We really are.
• 2:16
  Speaker 2: Okay. I want to understand exactly how we got here.
• 2:19
  Speaker 2: Because jumping from an atomic system to a nuclear system,
• 2:22
  Speaker 2: I mean, that sounds like a massive escalation in complexity.
• 2:26
  Speaker 3: It definitely is.
• 2:27
  Speaker 2: If atomic clocks are already coordinating our global GPS with
• 2:31
  Speaker 2: ridiculous precision, what exactly is the flaw we're trying to fix? Like,
• 2:35
  Speaker 2: why abandon them?
• 2:36
  Speaker 3: Well, to understand the limitation, you have to look at
• 2:39
  Speaker 3: how a conventional atomic clock actually works. We use atoms, right?
• 2:43
  Speaker 3: Usually elements like cesium or strontium. But specifically, we are
• 2:47
  Speaker 3: utilizing the electron cloud.
• 2:49
  Speaker 2: The negatively charged particles orbiting the center.
• 2:51
  Speaker 3: Right, exactly.
• 2:52
  Speaker 2: Scientists hit these electrons with lasers or microwaves. This excites them,
• 2:57
  Speaker 2: causing them to jump between different energy states.
• 2:59
  Speaker 3: And that jump is the tick.
• 3:02
  Speaker 2: Yes, that back and forth jump is the literal tick
• 3:04
  Speaker 2: of the clock.
• 3:05
  Speaker 3: Wait, but electrons, they form the outer shell of the atom, right?
• 3:09
  Speaker 3: They're the exterior layer interacting with the rest of the world.
• 3:13
  Speaker 1: Yes.
• 3:14
  Speaker 3: And that is precisely the vulnerability.
• 3:16
  Speaker 2: Oh, I see.
• 3:17
  Speaker 3: Because they are on the outside, they are continuously exposed
• 3:20
  Speaker 3: to their environment.
• 3:21
  Speaker 2: So it's like it's essentially a vulnerability of placement.
• 3:24
  Speaker 3: Yeah, kind of.
• 3:26
  Speaker 2: It's like having a grandfather clock sitting outside in a
• 3:28
  Speaker 2: massive storm, right? The pendulum is just getting blown around
• 3:30
  Speaker 2: by the wind.
• 3:31
  Speaker 3: That's a great way to put it.
• 3:33
  Speaker 2: Or like leaving a highly sensitive seismograph out in a
• 3:36
  Speaker 2: busy intersection. It's going to pick up the rumble of
• 3:38
  Speaker 2: every single passing truck.
• 3:39
  Speaker 3: Exactly. And for an atom, those trucks are things like
• 3:43
  Speaker 3: stray magnetic fields or electrical interference. Or even infinitesimal fluctuations
• 3:48
  Speaker 3: in the room temperature.
• 3:49
  Speaker 2: Wow, just the ambient temperature.
• 3:51
  Speaker 3: Yeah, all of these external forces push and pull on
• 3:54
  Speaker 3: those fragile outer electrons. We call this environmental noise.
• 3:58
  Speaker 2: And that noise messes up the ticking.
• 3:59
  Speaker 3: Right. It introduces incredibly tiny errors into the energy jumps
• 4:03
  Speaker 3: of those electrons, which means the ticking loses its perfect rhythm.
• 4:07
  Speaker 2: Okay, so if the outside of the atom is just
• 4:10
  Speaker 2: entirely too chaotic and exposed to all this noise, the
• 4:13
  Speaker 2: logical next step would be to look somewhere safer, right?
• 4:16
  Speaker 3: Somewhere deeper inside. And what's fascinating here is that you
• 4:20
  Speaker 3: bypass the fragile electron cloud entirely and you focus on
• 4:23
  Speaker 3: the atomic nucleus.
• 4:25
  Speaker 2: Which sits right at the dead center.
• 4:26
  Speaker 3: Exactly. It contains the protons and neutrons. But the critical
• 4:30
  Speaker 3: thing here is the scale. The nucleus is roughly 10,000
• 4:34
  Speaker 3: times smaller than the atom.
• 4:35
  Speaker 2: As a whole. 10,000 times smaller. That is, I mean,
• 4:39
  Speaker 2: so if the atom were the size of a massive
• 4:42
  Speaker 2: sports stadium, the nucleus would Would be like a single
• 4:46
  Speaker 2: marble sitting right on the 50-yard line.
• 4:49
  Speaker 3: That captures the scale perfectly. And because it is so
• 4:52
  Speaker 3: unimaginably tiny and so dense, it's largely unaffected by the environment.
• 4:57
  Speaker 2: Oh, wow. So it's just naturally immune to the storm.
• 5:00
  Speaker 3: Exactly. Furthermore, that electron cloud that causes so many problems
• 5:04
  Speaker 3: for atomic clocks, it actually serves a completely different function here.
• 5:08
  Speaker 2: Really?
• 5:08
  Speaker 3: It acts as a Faraday cage. It's literally a protective
• 5:11
  Speaker 3: shield that intercepts all those stray magnetic and electrical fields.
• 5:15
  Speaker 2: So the nucleus is just perfectly insulated inside? Yes.
• 5:18
  Speaker 3: A timekeeper based on the nucleus would theoretically be immune
• 5:22
  Speaker 3: to almost all the disturbances that ruin conventional atomic clocks.
• 5:26
  Speaker 2: Okay, looking at the pure logic of that, it sounds
• 5:28
  Speaker 2: incredibly straightforward. It does, yeah. I mean, if it's vastly
• 5:31
  Speaker 2: smaller and perfectly insulated, of course he'd use it to
• 5:34
  Speaker 2: build a clock. But you mentioned earlier this is a
• 5:37
  Speaker 2: breakthrough happening right now, like today.
• 5:39
  Speaker 3: Right.
• 5:40
  Speaker 2: If the theory is that simple, why did it take
• 5:42
  Speaker 2: us decades to actually build one? Why couldn't scientists in
• 5:45
  Speaker 2: the 80s or 90s just pick a random atom and
• 5:47
  Speaker 2: use its nucleus?
• 5:48
  Speaker 3: Well, because atomic nuclei are just notoriously stubborn when it
• 5:52
  Speaker 3: comes to absorbing energy.
• 5:53
  Speaker 2: So are now.
• 5:54
  Speaker 3: Remember, to create that ticking mechanism, you need to force
• 5:58
  Speaker 3: the particle to transition between two different energy states, a
• 6:01
  Speaker 3: resting state and an excited state.
• 6:04
  Speaker 2: Right. The jump. Exactly.
• 6:06
  Speaker 3: In a modern setup, you try to trigger this transition
• 6:08
  Speaker 3: by shining a highly focused laser at it. But the
• 6:11
  Speaker 3: energy gap between the resting and excited states in almost
• 6:14
  Speaker 3: all known atomic nuclei is just massive.
• 6:17
  Speaker 2: Massive meaning our lasers just aren't strong enough to force
• 6:19
  Speaker 2: the jump.
• 6:20
  Speaker 3: The lasers we currently have are orders of magnitude too weak.
• 6:24
  Speaker 3: The gap is simply too vast. Hitting a typical nucleus
• 6:27
  Speaker 3: with a standard laser literally does nothing.
• 6:30
  Speaker 2: It just ignores it. Yeah.
• 6:31
  Speaker 3: It doesn't absorb the light at all. It just sits there.
• 6:34
  Speaker 2: Okay. They just sit there in the dark entirely unresponsive.
• 6:36
  Speaker 2: That definitely explains the roadblock.
• 6:39
  Speaker 3: It was a huge problem.
• 6:40
  Speaker 2: But obviously they found a way around it, and it
• 6:42
  Speaker 2: involves a very specific element, thorium. What makes thorium the
• 6:46
  Speaker 2: exception to this rule?
• 6:47
  Speaker 3: So physicists suspected for decades that one highly specific isotope, thorium-229,
• 6:52
  Speaker 3: possessed this incredibly bizarre anomaly.
• 6:55
  Speaker 2: What kind of anomaly?
• 6:56
  Speaker 3: Theoretical calculations suggested it was a nuclear isomer, meaning they
• 7:00
  Speaker 3: believed the thorium-229 nucleus had two energy states that were
• 7:04
  Speaker 3: extraordinarily close together.
• 7:05
  Speaker 2: Oh, I see. Let me make sure I'm grasping this.
• 7:08
  Speaker 2: Instead of this massive, unbridgeable chasm between energy states that
• 7:12
  Speaker 2: requires some sci-fi laser to cross, thorium-229 has this tiny,
• 7:18
  Speaker 2: narrow gap?
• 7:18
  Speaker 3: Yes. The gap is so small that scientists realized they
• 7:22
  Speaker 3: wouldn't need theoretical super-powered lasers. A standard, highly-tuned ultraviolet laser could,
• 7:28
  Speaker 3: in theory, provide exactly the right amount of energy to
• 7:31
  Speaker 3: push it across that gap.
• 7:33
  Speaker 2: Allowing us to switch it from one state to the other.
• 7:35
  Speaker 3: Exactly. Exactly.
• 7:37
  Speaker 2: In theory. But proving that this gap actually existed in
• 7:40
  Speaker 2: reality seems to be where the timeline gets really grueling, right?
• 7:44
  Speaker 3: Oh, it was an exhaustive, decades-long hunt.
• 7:47
  Speaker 2: Because they had to figure out the exact frequency of
• 7:50
  Speaker 2: laser light required to hit this tiny gap.
• 7:53
  Speaker 3: Yeah, and when you don't know the exact frequency, you
• 7:55
  Speaker 3: are essentially scanning blindly across a vast spectrum of light.
• 7:59
  Speaker 2: Just hoping to see a reaction.
• 8:01
  Speaker 1: Right.
• 8:01
  Speaker 3: You shine a laser, check for absorption, adjust the frequency
• 8:05
  Speaker 3: slightly and try again. And again, it was just a
• 8:08
  Speaker 3: monumental task for the global physics community.
• 8:11
  Speaker 2: Which brings us to the recent breakthroughs. And I really
• 8:14
  Speaker 2: want to parse the timeline here because the progression of
• 8:16
  Speaker 2: the headlines can be a bit confusing.
• 8:18
  Speaker 3: It really can.
• 8:19
  Speaker 2: In April of 2024, a major announcement came out. A
• 8:22
  Speaker 2: team led by Professor Thorsten Schum at TU Wien, working
• 8:26
  Speaker 2: with Professor Eckhart Peick at PTB Braunschweig, they officially found
• 8:31
  Speaker 2: this long-suspected nuclear transition.
• 8:33
  Speaker 3: Yes, a massive moment.
• 8:35
  Speaker 2: They proved... in a real-world laboratory, that thorium nuclei could
• 8:39
  Speaker 2: be excited by laser beams.
• 8:40
  Speaker 3: Right. The April 2024 discovery proved the fundamental mechanics were sound.
• 8:45
  Speaker 3: They had finally found the precise frequency of light needed
• 8:48
  Speaker 3: to bridge the gap.
• 8:49
  Speaker 2: But here's where I'm getting hung up. By the fall
• 8:51
  Speaker 2: of 2024, just a few months later, the team demonstrated
• 8:55
  Speaker 2: they could use this exact thorium setup as a timekeeper.
• 8:59
  Speaker 3: They did.
• 8:59
  Speaker 2: So here's where it gets really interesting. If they were
• 9:02
  Speaker 2: already keeping time with a thorium nucleus back in late 2024,
• 9:07
  Speaker 2: why is this new development from October 2026 being hailed
• 9:11
  Speaker 2: as the first true standalone nuclear clock?
• 9:14
  Speaker 3: That is a great question.
• 9:15
  Speaker 2: I mean, weren't they already keeping time two years ago?
• 9:18
  Speaker 2: What is the fundamental difference between the 2024 build and
• 9:22
  Speaker 2: what's ticking right now?
• 9:24
  Speaker 3: The distinction really comes down to the concept of a
• 9:26
  Speaker 3: closed system. The apparatus they built in the fall of
• 9:29
  Speaker 3: 2024 was undeniably a massive leap. It was a functional
• 9:33
  Speaker 3: proof of concept.
• 9:34
  Speaker 2: But there was a catch.
• 9:35
  Speaker 3: A huge catch. It was entirely dependent on older technology.
• 9:39
  Speaker 3: The thorium setup could not run on its own.
• 9:42
  Speaker 2: Oh, wait. So it had to be, like, plugged into
• 9:44
  Speaker 2: something else.
• 9:45
  Speaker 3: Exactly. It had to be physically and computationally coupled to
• 9:49
  Speaker 3: a conventional, highly complex optical atomic clock.
• 9:52
  Speaker 2: So the 2024 version was essentially a hybrid. It was
• 9:55
  Speaker 2: measuring time using the nucleus... but it couldn't regulate itself.
• 9:59
  Speaker 3: Precisely. It relied on the traditional atomic clock's massive existing
• 10:03
  Speaker 3: infrastructure to keep the whole system stable, tune the lasers,
• 10:07
  Speaker 3: and make the measurements readable.
• 10:08
  Speaker 2: Oh, okay. That makes sense.
• 10:10
  Speaker 3: The October 2026 development from Vienna fundamentally severs that dependency.
• 10:15
  Speaker 3: The new machine, engineered by Luca Toscani de Cole and
• 10:18
  Speaker 3: the team at TU Wien, has completely cut the cord.
• 10:21
  Speaker 2: Wow. So it doesn't need the traditional atomic clock to
• 10:24
  Speaker 2: babysit it anymore?
• 10:26
  Speaker 3: Not at all. It is entirely self-stabilizing. In testing, it
• 10:30
  Speaker 3: actually ran continuously for over 24 hours without any outside intervention.
• 10:34
  Speaker 2: That is incredible. Going from a dependent module bolted onto
• 10:39
  Speaker 2: older tech to an independent self-regulating machine, that's a huge
• 10:43
  Speaker 2: engineering leap. It really is. I want to zoom in
• 10:46
  Speaker 2: on how this standalone machine actually functions on the lab bench.
• 10:49
  Speaker 2: Because when you say they're shooting lasers at a nuclear
• 10:53
  Speaker 2: isomer to measure time, my mind instantly goes to like
• 10:56
  Speaker 2: a massive, glowing, room-sized piece of science fiction hardware.
• 11:01
  Speaker 3: Yeah, that's what most people picture.
• 11:03
  Speaker 2: What does this device actually look like?
• 11:06
  Speaker 3: The reality is much more elegant. The core of this
• 11:09
  Speaker 3: entire machine is a highly specialized transparent crystal made of
• 11:13
  Speaker 3: calcium fluoride.
• 11:14
  Speaker 2: Just a small crystal. Yeah.
• 11:16
  Speaker 3: And during the manufacturing process, the team embedded the thorium
• 11:19
  Speaker 3: atoms directly into the lattice structure of this crystal. They
• 11:23
  Speaker 3: basically doped the crystal with thorium.
• 11:25
  Speaker 2: So instead of trying to trap a single floating atom
• 11:28
  Speaker 2: in a complex magnetic field, which is how I know
• 11:31
  Speaker 2: a lot of atomic clocks work. Right. They just physically
• 11:34
  Speaker 2: locked the thorium atoms inside a solid rock.
• 11:37
  Speaker 3: Exactly. It creates this remarkably stable, dense environment. This thorium-doped
• 11:43
  Speaker 3: crystal is continuously irradiated by a specific, highly-tuned ultraviolet laser beam.
• 11:49
  Speaker 3: And here is the critical part. It's the rhythmic oscillation
• 11:52
  Speaker 3: of the laser light itself, that incredibly fast, high-frequency electromagnetic
• 11:57
  Speaker 3: wave that serves as the actual ticking of the clock.
• 12:00
  Speaker 2: But if the laser is doing the ticking, how does
• 12:02
  Speaker 2: the system stay accurate?
• 12:03
  Speaker 3: What do you mean?
• 12:04
  Speaker 2: Well, any mechanical or optical system will naturally start to
• 12:08
  Speaker 2: drift over time, like The laser might experience a microscopic
• 12:11
  Speaker 2: drop in room temperature or a tiny vibration, and its
• 12:15
  Speaker 2: frequency will waver.
• 12:17
  Speaker 3: Right. That's a major issue in metrology.
• 12:19
  Speaker 2: In extreme high-precision metrology, even a fraction of a percent
• 12:23
  Speaker 2: of drift ruins the measurement. So it's almost like a
• 12:27
  Speaker 2: highly trained singer trying to hold one perfect continuous pitch. Okay.
• 12:31
  Speaker 3: I like that analogy.
• 12:32
  Speaker 2: But their voice naturally wavers over time. How does this
• 12:35
  Speaker 2: system correct itself without a human turning a dial? How
• 12:38
  Speaker 2: does the thorium crystal act as the vocal coach to
• 12:41
  Speaker 2: keep the pitch perfect?
• 12:42
  Speaker 3: That is exactly where the brilliance of the design comes in.
• 12:46
  Speaker 3: If we connect this to the bigger picture, it's done
• 12:48
  Speaker 3: through a beautifully engineered automatic feedback loop.
• 12:51
  Speaker 2: A feedback loop?
• 12:52
  Speaker 3: Yeah. This is where the specific properties of the thorium
• 12:55
  Speaker 3: nucleus shine. The thorium nuclei locked inside that crystal are
• 12:59
  Speaker 3: exceptionally strict about what they will interact with.
• 13:02
  Speaker 2: They only like that one specific frequency?
• 13:04
  Speaker 1: Exactly.
• 13:04
  Speaker 2: Exactly.
• 13:05
  Speaker 3: They will only absorb the laser light if the frequency
• 13:08
  Speaker 3: perfectly matches that tiny, narrow energy gap we talked about earlier.
• 13:12
  Speaker 2: Let me see if I can translate this feedback loop
• 13:15
  Speaker 2: into something a bit more tangible. Is it functionally similar to, like,
• 13:19
  Speaker 2: turning the tuning dial on an old analog car radio?
• 13:23
  Speaker 3: Oh, that's a good way to look at it.
• 13:24
  Speaker 2: Like, if you're trying to lock onto a specific station
• 13:27
  Speaker 2: and you drift even a millimeter off the exact frequency,
• 13:30
  Speaker 2: the music instantly drops out and you just get hit
• 13:32
  Speaker 2: with static.
• 13:33
  Speaker 3: Right.
• 13:34
  Speaker 2: So you know immediately to turn the dial back to
• 13:36
  Speaker 2: the center.
• 13:37
  Speaker 3: That is a very effective way to conceptualize the mechanism.
• 13:40
  Speaker 3: The thorium nuclei basically act as a hyper-specific radio receiver.
• 13:45
  Speaker 3: When the laser, the dial, is perfectly tuned, the nuclei
• 13:49
  Speaker 3: absorb the light. The signal is strong.
• 13:51
  Speaker 2: But if it drifts... If the.
• 13:52
  Speaker 3: Laser's frequency wavers even slightly from that optimum pitch, the
• 13:56
  Speaker 3: amount of light being absorbed by the crystal measurably drops.
• 13:59
  Speaker 2: The system here is the static.
• 14:01
  Speaker 3: Exactly. Photodiodes are constantly monitoring the light passing through the crystal.
• 14:06
  Speaker 3: The moment they detect a drop in absorption, the computational
• 14:09
  Speaker 3: system instantly recognizes the laser is drifting out of tune.
• 14:13
  Speaker 2: And it fixes it automatically. Yes.
• 14:15
  Speaker 3: Without any human input, it automatically sends an electrical signal
• 14:18
  Speaker 3: back to the laser hardware, nudging the frequency back until
• 14:21
  Speaker 3: the absorption spikes to maximum again.
• 14:24
  Speaker 2: Wow.
• 14:24
  Speaker 3: It is a completely closed continuous cycle. The clock actively
• 14:28
  Speaker 3: tunes itself in real time.
• 14:29
  Speaker 2: The thorium nuclei act as the ultimate unyielding quality control
• 14:33
  Speaker 2: for the laser. That is just a brilliant piece of engineering.
• 14:36
  Speaker 3: It really is a marvel.
• 14:38
  Speaker 2: So we have a device that automatically tunes itself using
• 14:42
  Speaker 2: the isolated, environmentally shielded nucleus of a thorium atom locked
• 14:47
  Speaker 2: inside a solid crystal.
• 14:48
  Speaker 3: Yep, that's the setup.
• 14:50
  Speaker 2: Based on that architecture, the logical assumption is that the
• 14:53
  Speaker 2: team in Vienna just turned on the most staggeringly accurate
• 14:56
  Speaker 2: timekeeper in human history.
• 14:58
  Speaker 3: You would think so, right?
• 15:00
  Speaker 2: Let's look at the numbers they published. Over a 24-hour period,
• 15:04
  Speaker 2: the precision of this prototype is approximately 10 to the
• 15:07
  Speaker 2: power of minus 15.
• 15:08
  Speaker 3: Which is an absurdly small number.
• 15:11
  Speaker 2: Right. In practical terms, that translates to an error rate
• 15:14
  Speaker 2: of roughly one single second in 30 million years.
• 15:18
  Speaker 3: It is a level of precision that just fundamentally challenges
• 15:22
  Speaker 3: our everyday comprehension of time.
• 15:24
  Speaker 2: So what does this all mean? If you had started
• 15:27
  Speaker 2: this clock ticking 30 million years ago, long before humans
• 15:30
  Speaker 2: even existed, and let it run continuously until today, it
• 15:33
  Speaker 2: would only be off by a single second.
• 15:35
  Speaker 3: Right.
• 15:36
  Speaker 2: That sounds unbeatable. So this must be the absolute world record, right?
• 15:40
  Speaker 2: This prototype has officially crushed the old optical atomic clocks.
• 15:44
  Speaker 3: Well, this raises an important question about how we measure
• 15:47
  Speaker 3: progress in physics. It is highly counterintuitive, but an error
• 15:51
  Speaker 3: rate of one second in 30 million years is not
• 15:55
  Speaker 3: a world record.
• 15:56
  Speaker 2: Wait, really?
• 15:57
  Speaker 3: Yeah.
• 15:57
  Speaker 2: A clock that barely loses a second across geological eras
• 16:01
  Speaker 2: is not the most precise instrument we have.
• 16:04
  Speaker 3: No, it's not.
• 16:05
  Speaker 2: Okay.
• 16:05
  Speaker 3: The world's absolute best optical atomic clocks, the pinnacle of
• 16:09
  Speaker 3: that older electron-based technology, they are currently more precise than
• 16:13
  Speaker 3: this nuclear prototype.
• 16:14
  Speaker 2: They have a tighter error rate.
• 16:16
  Speaker 3: They do.
• 16:16
  Speaker 2: Okay, I have to stop you there because that feels
• 16:19
  Speaker 2: like a massive contradiction.
• 16:20
  Speaker 3: I know it does.
• 16:21
  Speaker 2: If the old atomic technology is currently winning the race...
• 16:24
  Speaker 2: Why is the global scientific community treating the Vienna clock
• 16:28
  Speaker 2: like a historic triumph? I mean, why did Professor Shum
• 16:31
  Speaker 2: call this a fantastic result for a prototype if it's
• 16:34
  Speaker 2: technically slower out of the gate than the machine it's
• 16:36
  Speaker 2: trying to replace?
• 16:38
  Speaker 3: Because you have to evaluate the trajectory of a technology,
• 16:40
  Speaker 3: not just its current snapshot.
• 16:42
  Speaker 2: Okay. Unpack that for me.
• 16:44
  Speaker 3: Conventional optical atomic clocks have benefited from decades of relentless
• 16:48
  Speaker 3: obsessive refinement by the brightest minds in metrology. They are heavily,
• 16:52
  Speaker 3: heavily optimized. Right. But they are essentially hitting the theoretical
• 16:56
  Speaker 3: ceiling of what is physically possible. When you rely on
• 16:59
  Speaker 3: the fragile electron cloud of an atom, there's just a
• 17:02
  Speaker 3: hard limit to how much environmental noise you can eliminate.
• 17:05
  Speaker 2: So they are bumping up against the laws of physics.
• 17:07
  Speaker 2: They simply cannot get much better.
• 17:09
  Speaker 3: Exactly. They are amazing instruments, but they have maxed out
• 17:14
  Speaker 3: their potential. The new nuclear clock from Vienna, however, is
• 17:18
  Speaker 3: merely a first-generation prototype.
• 17:20
  Speaker 2: Ah, I see. It hasn't been optimized yet.
• 17:23
  Speaker 3: It hasn't been optimized at all. The reason this is
• 17:25
  Speaker 3: a fantastic result is that atomic nuclei have the fundamental
• 17:29
  Speaker 3: mathematical capacity for far higher precision than whole atoms ever could.
• 17:34
  Speaker 2: The foundation has been successfully laid. Yes.
• 17:37
  Speaker 3: The proof of concept for a standalone, self-stabilizing nuclear system
• 17:41
  Speaker 3: is alive and ticking on a lab bench.
• 17:43
  Speaker 2: So an error rate of one second in 30 million
• 17:46
  Speaker 2: years is just the baseline. It's the floor for nuclear technology,
• 17:50
  Speaker 2: whereas it's Basically the absolute ceiling for atomic technology. Precisely.
• 17:55
  Speaker 3: The engineering roadmap from here is incredibly clear. Over the
• 17:58
  Speaker 3: coming years, teams are going to introduce stronger, more highly
• 18:02
  Speaker 3: stabilized lasers.
• 18:03
  Speaker 2: They'll refine the materials.
• 18:04
  Speaker 3: Yeah, they will engineer even purer, more refined calcium fluoride crystals.
• 18:09
  Speaker 3: As those incremental improvements are made, this technology will not
• 18:12
  Speaker 3: just eventually match the older atomic clocks, it is mathematically
• 18:16
  Speaker 3: projected to drastically surpass them.
• 18:19
  Speaker 2: It will completely shatter the previous limits of metrology.
• 18:22
  Speaker 3: It will. We are looking at the very first prototype
• 18:25
  Speaker 3: of a completely new engine. It might not outpace a
• 18:28
  Speaker 3: highly refined version of the old tech today, but it
• 18:31
  Speaker 3: represents a mechanical shift that will eventually leave the old
• 18:34
  Speaker 3: methods entirely obsolete.
• 18:36
  Speaker 2: That makes total sense. We are watching the transition phase
• 18:39
  Speaker 2: between two eras of measurement.
• 18:41
  Speaker 3: We really are.
• 18:42
  Speaker 2: And that brings us to the ultimate question of why you,
• 18:45
  Speaker 2: listening to this, should actually care about a bunch of
• 18:48
  Speaker 2: physicists in Vienna building a hyper-accurate clock.
• 18:51
  Speaker 3: That's an important question.
• 18:52
  Speaker 2: Because it's easy to assume this is just an academic
• 18:54
  Speaker 2: exercise and making sure your smartwatch is perfectly synchronized or
• 18:58
  Speaker 2: that a calendar is flawlessly aligned.
• 19:00
  Speaker 3: Right.
• 19:01
  Speaker 2: But extreme metrology isn't just about keeping schedules. Time is
• 19:05
  Speaker 2: the bedrock variable in almost every major equation we use
• 19:08
  Speaker 2: to understand the physical universe.
• 19:10
  Speaker 3: That is the crucial takeaway. Time is the ultimate ruler.
• 19:14
  Speaker 3: When you push the boundaries of how precisely you can
• 19:16
  Speaker 3: measure a second, you inherently push the boundaries of how
• 19:19
  Speaker 3: precisely you can measure everything else.
• 19:21
  Speaker 2: Because everything else depends on it.
• 19:23
  Speaker 3: Exactly. When your ruler for time gets exponentially sharper, your
• 19:26
  Speaker 3: ability to measure distance, velocity, and subtle physical forces becomes
• 19:31
  Speaker 3: exponentially sharper as well.
• 19:33
  Speaker 2: We use time to measure how the universe bends and flexes.
• 19:36
  Speaker 2: We're literally entering an age where our instruments will be
• 19:38
  Speaker 2: sensitive enough to detect phenomena that have been entirely invisible
• 19:42
  Speaker 2: to us up until this point.
• 19:43
  Speaker 3: It opens up a whole new frontier.
• 19:45
  Speaker 2: Which leaves you with a truly profound concept to consider.
• 19:48
  Speaker 2: We are on the verge. of deploying a network of
• 19:51
  Speaker 2: nuclear clocks that are vastly more precise than anything currently
• 19:55
  Speaker 2: in existence. Clocks that are so stable and so perfectly
• 19:59
  Speaker 2: insulated deep inside the nucleus of a thorium atom that
• 20:02
  Speaker 2: they are completely deaf to the chaotic noise of our environment.
• 20:06
  Speaker 3: They won't be distracted by the noise.
• 20:08
  Speaker 2: Exactly. And if our timekeepers are no longer distracted by
• 20:12
  Speaker 2: the noise, what hidden microscopic forces in the universe might
• 20:17
  Speaker 2: we suddenly be able to hear ticking in the background?
• 20:20
  Speaker 3: It's a staggering thought.
• 20:21
  Speaker 2: If a clock is sensitive enough, could we use it
• 20:25
  Speaker 2: to measure the incredibly subtle shifting ripples of gravity as
• 20:29
  Speaker 2: massive objects collide millions of light years away? Could we
• 20:33
  Speaker 2: finally detect the invisible theoretical influence of dark matter? simply
• 20:37
  Speaker 2: because we finally possess an instrument sharp enough to notice
• 20:41
  Speaker 2: it warping the very fabric of time itself.