WEBVTT

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<v Speaker 1>Welcome to Bedtime Astronomy. Explore the wonders of the cosmos

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<v Speaker 1>with our soothing Bedtime Astronomie podcast. Each episode offers a

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<v Speaker 1>gentle journey through the stars, planets, and beyond, perfect for

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<v Speaker 1>unwinding after a long day. Let's travel through the mysteries

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<v Speaker 1>of the universe as you drift off into a peaceful

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<v Speaker 1>slumber under the night sky.

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<v Speaker 2>Imagine standing outside on a really dark night, just looking

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<v Speaker 2>up at the stars. You've probably been told that everything

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<v Speaker 2>up there is accelerating away from us, right, push by

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<v Speaker 2>this mysterious invisible force called dark energy, right.

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<v Speaker 3>Which supposedly makes up roughly what seventy percent of our universe?

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<v Speaker 2>Exactly seventy percent. But uh, what if I told you

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<v Speaker 2>that dark energy just doesn't actually exist? Like, what if

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<v Speaker 2>it's just a mathematical ghoth that we invented to cover

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<v Speaker 2>up a gaping hole in our understanding of gravity.

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<v Speaker 3>I mean that fundamentally depends how we view reality. If

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<v Speaker 3>dark energy is just a phantom placeholder, it means the

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<v Speaker 3>standard model of cosmology, the whole framework we use to

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<v Speaker 3>understand the origin and fate of the universe, it has

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<v Speaker 3>a massive flaw right at its center.

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<v Speaker 2>Yeah, it's wild to think about. So today's deep dive

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<v Speaker 2>is going to explore a really radical new framework from

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<v Speaker 2>theoretical physicists Walmagueyo and re Out of Imperial College London.

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<v Speaker 3>Oh, this is such an exciting theory.

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<v Speaker 2>It really is. They published a theory attempting to explain

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<v Speaker 2>the acceleration of the cosmos without a single drop of

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<v Speaker 2>dark energy. Instead, they're looking at the universe entirely through

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<v Speaker 2>the lens of thermodynamics, you know, like the physics of

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<v Speaker 2>heat and engines and energy transfer.

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<v Speaker 3>Which is a completely entirely different paradigm completely.

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<v Speaker 2>Okay, let's unpack this, because if we want to throw

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<v Speaker 2>out dark energy, we really have to start with the

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<v Speaker 2>problem that forced us to invent it in the first place.

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<v Speaker 3>Right to understand why we're even looking at a new theory,

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<v Speaker 3>we have to look at why the absolute gold standard

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<v Speaker 3>of physics is currently failing us. I mean, Albert Einstein's

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<v Speaker 3>theory of general relativity is arguably one of the most

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<v Speaker 3>successful scientific theories of all time. Absolutely, it tells us

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<v Speaker 3>that gravity isn't just some invisible tether pulling planets together.

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<v Speaker 3>It is the actual curving and warping of a four

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<v Speaker 3>dimensional fabric called space time.

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<v Speaker 2>Right, So, heavy objects like stars essentially bend this fabric,

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<v Speaker 2>and that curvature dictates how other objects.

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<v Speaker 3>Move exactly, and it works wonderfully almost everywhere we look.

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<v Speaker 3>It predicts the weird orbit of mercury around our sun.

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<v Speaker 3>It explains how light bends around a black hole.

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<v Speaker 2>I mean, it's the only reason the GPS satellites orbiting

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<v Speaker 2>the Earth can successfully pinpoint your phone on a map.

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<v Speaker 3>Right, Yeah, without general relativity, your GPS would be off

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<v Speaker 3>by miles every single day. But the problem is, when

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<v Speaker 3>you zoom out to the scale of the entire universe,

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<v Speaker 3>Einstein's framework just hits a wall.

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<v Speaker 2>And this is what's known as the cosmological constant problem.

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<v Speaker 3>Right, that's the one, and honestly, it is arguably the

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<v Speaker 3>most embarrassing mismatch in the history of theoretical physics.

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<v Speaker 2>Okay, so I know this involves empty space, But why

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<v Speaker 2>is measuring literally nothing so incredibly complicated?

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<v Speaker 3>Well, because empty space isn't actually empty.

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<v Speaker 2>Wait, what do you mean If.

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<v Speaker 3>You take a patch of space and just remove every

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<v Speaker 3>single atom, every photon of light, every trace of matter,

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<v Speaker 3>you might think you're left with zero energy, But quantum

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<v Speaker 3>mechanics tells us a very different story.

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<v Speaker 2>H Right, The quantum world is always.

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<v Speaker 3>Messy, very messy. It operates on a principle of constant fluctuation.

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<v Speaker 3>Even in a perfect vacuum, these virtual particles are constantly

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<v Speaker 3>bubbling into existence and popping back out. Empty space is

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<v Speaker 3>basically a boiling, turbulent sea of quantum energy.

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<v Speaker 2>Okay, so quantum physicists can actually calculate how much energy

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<v Speaker 2>is bubbling in this cosmic vacuum, right.

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<v Speaker 3>They can. But when they run the math to predict

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<v Speaker 3>how much energy should be an empty space, the number

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<v Speaker 3>they get is just unimaginably huge. It is a one

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<v Speaker 3>followed by one hundred and twenty zeros.

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<v Speaker 2>Fee to one. With one hundred and twenty zeros, that's

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<v Speaker 2>I can't even fathom a number that large.

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<v Speaker 3>Nobody can. It's absurdly huge.

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<v Speaker 2>But when astronomers actually point their telescopes out into the darkest,

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<v Speaker 2>emptiest patches of the night sky, we don't see an explosive,

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<v Speaker 2>boiling universe. The observed energy of empty space is microscopic.

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<v Speaker 3>It's absolutely tiny. So we have this unbridgable gap between

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<v Speaker 3>the quantum world, which predicts a violently energetic vacuum and

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<v Speaker 3>the cosmic world, which observes a very calm.

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<v Speaker 2>One in general relativity just simply cannot reconcile these two realities.

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<v Speaker 3>No, the math totally breaks down, And this huge discrepancy

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<v Speaker 3>is exactly why physicists introduce dark energy. It was basically

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<v Speaker 3>a way to mathematically balance the cosmic books, just to.

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<v Speaker 2>Explain why the universe is expanding the way it is

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<v Speaker 2>without tossing out Einstein.

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<v Speaker 3>Entirely precisely, they needed a patch for the whole.

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<v Speaker 2>But if Einstein's math is creating this unbridgable gap, it

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<v Speaker 2>means we can't just tweak general relativity, right, We have

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<v Speaker 2>to derive gravity from a completely different starting point. Has

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<v Speaker 2>anyone actually tried to build gravity from scratch using something else?

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<v Speaker 3>They have? Actually, Back in nineteen ninety five, a physicist

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<v Speaker 3>named Ted Jacobson published a seminal paper doing exactly that.

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<v Speaker 2>Okay, nineteen ninety five, that's a while ago. What was

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<v Speaker 2>his approach?

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<v Speaker 3>Well before Jacobson, the physicists like Stephen Hawking had already

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<v Speaker 3>proven that black holes have a temperature and they have entropy.

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<v Speaker 2>Oh right, Hawking radiation.

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<v Speaker 3>Exactly So, in other words, Einstein's gravity possesses thermal properties.

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<v Speaker 3>Jackson looked at that relationship and wondered if it could

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<v Speaker 3>be a two way street.

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<v Speaker 2>Oh I see, he ran the logic in reverse. Instead

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<v Speaker 2>of saying gravity has a temperature, he asked if temperature

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<v Speaker 2>and heat can actually create gravity.

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<v Speaker 3>That is the crucial pivot right there. Jacobson started with

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<v Speaker 3>the foundational laws of thermodynamics. Think about what entropy really is.

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<v Speaker 3>It's a measure of hidden information or disorder in a system.

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<v Speaker 2>Right like a shattered coffee mug has more entropy than

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<v Speaker 2>a whole one exactly.

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<v Speaker 3>Jacobson connected the entropy of a patch of space to

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<v Speaker 3>the actual surface area of that space. He showed mathematically

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<v Speaker 3>that if heat flows across a boundary in space, the

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<v Speaker 3>entropy changes. Okay, To accommodate that change in entropy, the

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<v Speaker 3>actual geometry of the space has to warp and bend.

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<v Speaker 2>And warping space time is the literal definition of gravity.

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<v Speaker 2>So he used the laws of heat to mathematically derive

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<v Speaker 2>Einstein's equations of general relativity.

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<v Speaker 3>He really did. He built Einstein's theory using nothing but thermodynamics.

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<v Speaker 2>It is amazing.

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<v Speaker 3>What's fascinating here is that it proved gravity might not

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<v Speaker 3>be a fundamental force at all. It might just be

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<v Speaker 3>a large scale emergent property of heat and energy, much

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<v Speaker 3>like how the temperature of a room is just an

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<v Speaker 3>emergent property of billions of invisible air molecules bouncing off

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<v Speaker 3>each other.

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<v Speaker 2>Wow. So if Jacobs improved gravity is thermodynamic back in

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<v Speaker 2>nineteen ninety five, why are we only getting this new

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<v Speaker 2>dark energy killing framework right now? What took almost thirty years?

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<v Speaker 3>Because the math is agonizingly difficult and physicists just got stuck.

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<v Speaker 3>Jean Maguejo, the senior author of this new paper, read

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<v Speaker 3>Jacobson's work right after finishing his PhD, and he was

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<v Speaker 3>utterly captivated by it.

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<v Speaker 2>He couldn't figure out.

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<v Speaker 3>He spent years decades really trying to build on it

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<v Speaker 3>and feeling every single time he tried to push the

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<v Speaker 3>idea forward the equations just fell apart.

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<v Speaker 2>What was the roadblock? What was he doing wrong?

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<v Speaker 3>Well, he, along with almost everyone else in the field,

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<v Speaker 3>was trying to take Jacobson's thermodynamic construction and retrofit it

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<v Speaker 3>to match existing theories.

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<v Speaker 2>Oh, because they already knew what the final picture of

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<v Speaker 2>gravity was supposed to look like. They had Einstein's template right.

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<v Speaker 3>So they were trying to force these new thermodynamic puzzle

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<v Speaker 3>pieces into Einstein's predetermined box.

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<v Speaker 2>It sounds like trying to write a song where you

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<v Speaker 2>already know you have to end on a specific chord progression,

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<v Speaker 2>and it's just making the whole creative process feel unnatural

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<v Speaker 2>and broken.

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<v Speaker 3>That's a perfect analogy. The turning point didn't actually come

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<v Speaker 3>until mcgueo was on holiday on a remote Greek island,

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<v Speaker 3>a Greek island, nice, yeah, and he had absolutely no

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<v Speaker 3>Internet access, no distractions, and he suddenly realized his underlying

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<v Speaker 3>approach was flawed. He needed to wipe the slate clean.

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<v Speaker 2>So he stopped trying to force the math to recreate

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<v Speaker 2>standard gravity exactly.

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<v Speaker 3>He decided to start purely with thermal physics, follow the

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<v Speaker 3>equations blindly, and just accept whatever weird, unprecedented theory of

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<v Speaker 3>gravity naturally emerged on the other side.

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<v Speaker 2>I mean, that is a massive leap of faith for

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<v Speaker 2>a theoretical physicist. You're basically saying, I'm going to abandon

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<v Speaker 2>the most elegant, proven theory of the twentieth century just

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<v Speaker 2>to see where this raw thermal math takes me.

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<v Speaker 3>It requires an incredible amount of intellectual bravery. Honestly, general

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<v Speaker 3>relativity works so perfectly on the local scale that letting

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<v Speaker 3>go of it to follow thermodynamic equations requires you to

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<v Speaker 3>accept that the universe might look entirely alien compared to

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<v Speaker 3>what we currently believe.

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<v Speaker 2>Okay, So mcguasho gets back from his island epiphany, he

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<v Speaker 2>teams up with his PhD student Race at Shay, and

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<v Speaker 2>they start building a brand new theory of gravity purely

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<v Speaker 2>from thermal physics.

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<v Speaker 3>Right.

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<v Speaker 2>But they don't look at colliding galaxies or supermassive black holes.

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<v Speaker 2>They look at engines. Specifically, they frame the gravity of

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<v Speaker 2>the universe as an autocycle.

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<v Speaker 3>Yep, an autocycle.

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<v Speaker 2>Waits up an autocycle like the internal combustion engine sitting

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<v Speaker 2>under the hood of a standard gasoline.

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<v Speaker 3>Car, the very same engine.

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<v Speaker 2>Let me visualize this because it sounds completely absurd. In

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<v Speaker 2>my car, I have fuel injecting into a cylinder, A

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<v Speaker 2>spark plug ignites it. The resulting explosion pushes a physical

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<v Speaker 2>metal piston down, which turns a crank shaft, which spins

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<v Speaker 2>my wheels.

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<v Speaker 3>That's the basic mechanics. Y.

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<v Speaker 2>How on earth do you apply a mechanical car engine

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<v Speaker 2>to the four dimensional fabric of space time, like, what

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<v Speaker 2>is the piston in the universe?

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<v Speaker 3>Well, it helps to step back and look at what

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<v Speaker 3>an engine is doing on a thermodynamic level. When physicists

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<v Speaker 3>previously tried to link gravity and heat, they were essentially

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<v Speaker 3>only looking at heat flowing from a hot place to

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<v Speaker 3>a cold place. Okay, but that is the simplest, most

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<v Speaker 3>passive form of thermodynamics. Think of a hot cup of

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<v Speaker 3>coffee cooling down on a desk. That's just basic heat transfer.

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<v Speaker 3>An engine is different. An engine involves actual work.

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<v Speaker 2>Right, The heat in a car engine is being actively

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<v Speaker 2>converted into mechanical work to move a two ton vehicle

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<v Speaker 2>down the highway exactly.

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<v Speaker 3>And Mgueo andysa Kai realized that previous cosmic models were

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<v Speaker 3>completely ignoring the work aspect. They were treating the universe

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<v Speaker 3>like a cooling cup of coffee rather than a dynamic machine.

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<v Speaker 2>So they injected these missing elements into the math.

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<v Speaker 3>Yes, and to do this they set up a theoretical

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<v Speaker 3>framework using something called a causal diamond.

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<v Speaker 2>Okay, a causal diamond are we talking about like actual

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<v Speaker 2>geometry floating in space.

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<v Speaker 3>Not a physical object. No, think of a causal diamond

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<v Speaker 3>as a localized bubble of space time A bubble, got it,

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<v Speaker 3>Because the speed of light is the absolute speed limit

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<v Speaker 3>of the universe. There is a strict boundary on how

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<v Speaker 3>far a signal or ray of light can travel in

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<v Speaker 3>a set amount of time.

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<v Speaker 2>Right, nothing can go faster than.

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<v Speaker 3>Life exactly, So a causal diamond represents that limit. It

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<v Speaker 3>is an isolated bubble representing the maximum region of space

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<v Speaker 3>where events can actually influence each other. They use this

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<v Speaker 3>bubble as a tiny theoretical laboratory.

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<v Speaker 2>So they let heat flow in and out of the

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<v Speaker 2>boundaries of this space time bubble. But they also calculated

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<v Speaker 2>the thermodynamic work happening inside it. That's right, But I'm

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<v Speaker 2>still stuck on my question from earlier. What is the

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<v Speaker 2>universe's version of a piston? What is the work actually doing.

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<v Speaker 3>So the gas inside the cosmic engine is the energy

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<v Speaker 3>of the universe itself, and the piston is the physical

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<v Speaker 3>boundary of that space time bubble. Okay, when the internal

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<v Speaker 3>combustion happens in this thermodynamic sense, the energy does work

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<v Speaker 3>to physically stretch the fabric of space time. The universe

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<v Speaker 3>doing the work to expand its own boundaries is the

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<v Speaker 3>mathematical equivalent of the hot gas pushing the metal piston

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<v Speaker 3>in your car.

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<v Speaker 2>Okay, that actually makes sense. The expansion of space itself

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<v Speaker 2>is the mechanical work exactly. But when they ran the

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<v Speaker 2>math on this cosmic engine treating gravity this way, they

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<v Speaker 2>hit a result so shocking they almost threw the whole

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<v Speaker 2>paper in the trash. The mass revealed a gravitational theory

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<v Speaker 2>where matter and energy could be continuously created or destroyed.

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<v Speaker 3>Which is usually a massive, massive red flag.

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<v Speaker 2>Here's where it gets really interesting, though, because you and

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<v Speaker 2>I both know the conservation of mass and energy is

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<v Speaker 2>basically rule number one in physics. You can't just break

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<v Speaker 2>a fundamental law of the universe.

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<v Speaker 3>Well, you really can.

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<v Speaker 2>It is drilled into every science student from day one.

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<v Speaker 2>Energy cannot be created or destroyed, only transformed. If I

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<v Speaker 2>turned in a high school physics test where I just

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<v Speaker 2>magically conjured new matter out of nowhere, I would fail.

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<v Speaker 3>You definitely fail.

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<v Speaker 2>How did this not immediately get thrown out as a

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<v Speaker 2>fundamental math error.

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<v Speaker 3>Because normally it would be. If your equations violate the

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<v Speaker 3>conservation of energy, you almost always assume you dropped a

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<v Speaker 3>minus sign or you carried a zero wrong somewhere Migueo

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<v Speaker 3>and Ech felt exactly the same way. Their immediate instinct

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<v Speaker 3>was that their theory was fundamentally broken.

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<v Speaker 2>They thought they just messed up the calculations.

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<v Speaker 3>But they checked the math, and they checked it again.

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<v Speaker 3>It was sound. The thermodynamic engine model absolutely demanded that

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<v Speaker 3>the conservation laws be modified.

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<v Speaker 2>So instead of throwing it away, they decided to follow

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<v Speaker 2>the math and apply this broken rule to the universe

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<v Speaker 2>as a hole to see what would happen.

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<v Speaker 3>They asked a terrifying question, what if this isn't a

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<v Speaker 3>bug but a feature. To understand why this is so profound,

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<v Speaker 3>we really have to look at the standard model of

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<v Speaker 3>cosmology again. Okay, In our normal universe, matter has positive

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<v Speaker 3>mass and it exerts gravity. Gravity pulls things together. So

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<v Speaker 3>as the universe expands from the Big Bang, all the

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<v Speaker 3>galaxy stars in dark matter should be pulling on each

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<v Speaker 3>other gravitationally.

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<v Speaker 2>Right, this collective poll should be acting like a giant

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<v Speaker 2>brake pedal, slowing the expansion of the universe down.

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<v Speaker 3>It should be decelerating.

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<v Speaker 2>But we know from observing distant supernovas that the universe

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<v Speaker 2>isn't decelerating, It is accelerating. The brake pedal isn't working

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<v Speaker 2>someone is actively slamming on the gas. Yes, and that

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<v Speaker 2>is why we invented dark energy to begin with, to

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<v Speaker 2>act as a mysterious anti gravity force pushing everything apart

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<v Speaker 2>to counteract the pulling of normal matter.

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<v Speaker 3>Right. So, now let's apply Mguejo and Isaka's engine model

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<v Speaker 3>to that scenario. In their thermodynamic gravity, the strict conservation

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<v Speaker 3>law is modified. It allows for the continuous creation of

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<v Speaker 3>new matter and energy as the universe hums along. If

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<v Speaker 3>matter is continuously being generated while the universe expands, it

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<v Speaker 3>fundamentally alters how the thermodynamics of the cosmos operate.

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<v Speaker 2>Would I need to wrap my head around this. If

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<v Speaker 2>you are creating more matter, wouldn't you just have more

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<v Speaker 2>gravity pulling things together. Wouldn't more matter hit the brake

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<v Speaker 2>pedal even harder?

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<v Speaker 3>That is the intuitive assumption. Yes, yes, but thermodynamics operates differently.

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<v Speaker 3>It all comes down to pressure. Yeah. In a closed system,

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<v Speaker 3>if you suddenly start continuously generating new material to keep

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<v Speaker 3>your engine running, that continuous generation actually alters the thermodynamic

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<v Speaker 3>equation of state. Instead of acting like normal passive matter

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<v Speaker 3>that just polls this continuously generated matter exerts a global

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<v Speaker 3>negative pressure.

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<v Speaker 2>Negative pressure, What does that even mean in space?

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<v Speaker 3>Think of a dry sponge. If you let it soak

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<v Speaker 3>up water, the sponge expands outward. Right The act of

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<v Speaker 3>drawing in new material pushes the boundaries of the sponge apart.

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<v Speaker 3>Oh wow, and the cosmic engine, the continuous mathematical creation

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<v Speaker 3>of energy required to satisfy this modified autocycle, produces a

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<v Speaker 3>negative pressure that physically pushes the boundaries of space time outward.

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<v Speaker 2>So the matter itself, through the act of its own

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<v Speaker 2>continuous creation, drives the acceleration exactly. My mind is genuinely

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<v Speaker 2>blown right now, because if the modified nature of matter itself,

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<v Speaker 2>functioning through this engine like cycle, is generating that outward

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<v Speaker 2>negative pressure, you don't need dark energy at all.

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<v Speaker 3>The phantom placeholder vanishes completely.

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<v Speaker 2>That is wild. You solve the cosmological constant problem, You

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<v Speaker 2>explain the accelerating universe, and you get rid of a

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<v Speaker 2>mysterious force making up seventy percent of reality, all just

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<v Speaker 2>by treating gravity as a thermodynamic engine.

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<v Speaker 3>It is a beautifully elegant, incredibly clean mathematical fix.

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<v Speaker 2>It really is incredibly elegant. It links the mundane physics

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<v Speaker 2>of a combustion engine with the grand mysteries of astronomy.

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<v Speaker 2>But in modern physics, elegant math doesn't automatically rewrite the textbooks.

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<v Speaker 3>No, it definitely doesn't. If we connect this to the

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<v Speaker 3>bigger picture, we have to bring this back down to reality,

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<v Speaker 3>because creating a gorgeous theoretical model on a whiteboard is very,

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<v Speaker 3>very different from proving it exists in nature. Mcgueo himself

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<v Speaker 3>is very candid about this. Actually, he pointed out that

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<v Speaker 3>back in nineteen ninety when he was just starting out

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<v Speaker 3>in physics, cosmology was a very loose field. We didn't

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<v Speaker 3>have the ultrasensitive detectors or the massive space telescopes we

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<v Speaker 3>have today.

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<v Speaker 2>So because there was a severe lack of hard data,

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<v Speaker 2>theoretical physicists could hypothesize almost anything pretty much.

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<v Speaker 3>Yeah, you could build these beautiful mathematical castles in the sky,

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<v Speaker 3>and because the telescopes weren't powerful enough to check your work,

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<v Speaker 3>no one could definitely prove you wrong.

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<v Speaker 2>But today you cannot get away with building castles in

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<v Speaker 2>the sky. Cosmology is a ruthless, rigidly data driven field.

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<v Speaker 3>It really is. We have mapped the microscopic tricher fluctuations

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<v Speaker 3>in the cosmic microwave background, you know, the leftover heat

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<v Speaker 3>from the Big Bang. We have instruments like DSi, the

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<v Speaker 3>Dark Energy Spectroscopic Instrument, meticulously tracking how millions of galaxies

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<v Speaker 3>are moving and clustering over time. We just have mountains

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<v Speaker 3>of high precision observational.

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<v Speaker 2>Data now, which means this thermodynamic engine theory has to

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<v Speaker 2>go to war. I think MCGUEO calls it the gauntlet

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<v Speaker 2>of observation.

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<v Speaker 3>Exactly the gauntlet this model is in its absolute infancy.

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<v Speaker 3>It is highly speculative. For it to survive, it must

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<v Speaker 3>be rigorously tested against the data we are pulling down

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<v Speaker 3>from the James Web Space Telescope and other observatories.

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<v Speaker 2>So the researchers now have to calculate exactly how their

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<v Speaker 2>modified matter would behave over billions of years.

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<v Speaker 3>Right, They have to ask does it perfectly predict the

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<v Speaker 3>expansion rates we actually measure, does the continuous creation of

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<v Speaker 3>matter leave a signature in the cosmic microwave.

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<v Speaker 2>Background, or does it align with how galaxies actually clump

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<v Speaker 2>together in the real universe exactly?

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<v Speaker 3>All that has to match up.

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<v Speaker 2>So what does this all mean? We started this journey

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<v Speaker 2>looking up at the night sky, assuming everything was being

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<v Speaker 2>pushed apart by an invisible ghost called dark energy. But

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<v Speaker 2>by tracking the work of physicists willing to abandon assumptions,

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<v Speaker 2>we've seen a totally different.

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<v Speaker 3>Possibility, a really fascinating one from.

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<v Speaker 2>Ted Jacobson proving you can build gravity from heat to

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<v Speaker 2>a Greek Island epiphany that told us to stop forcing

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<v Speaker 2>puzzle pieces to fit. We've seen how treating the fabric

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<v Speaker 2>of space time like an internal combustion engine, focusing on

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<v Speaker 2>mechanical work, not just heat flow, leads to a universe

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<v Speaker 2>where the rules of conservation are literally rewritten. By allowing

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<v Speaker 2>matter and energy to be continuously created, we arrive at

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<v Speaker 2>a universe that accelerates itself through negative pressure cleanly and elegantly,

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<v Speaker 2>without a single drop of dark energy.

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<v Speaker 3>Whether it survives the gauntlet of hard data or gets

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<v Speaker 3>discarded like so many theories before it, it is a

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<v Speaker 3>profound reminder that we must constantly question our most basic assumptions.

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<v Speaker 3>Sometimes the fundamental rules we learn in high school are

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<v Speaker 3>the very things preventing us from seeing the true pattern

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<v Speaker 3>of reality.

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<v Speaker 2>It really is a massive paradigm shift, and it leaves

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<v Speaker 2>you with a truly staggering thought to mull over the

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<v Speaker 2>next time you are standing outside looking up at those stars.

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<v Speaker 2>Under the old model of dark energy, the universe just

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<v Speaker 2>expands faster and faster until everything freezes in a lonely

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<v Speaker 2>isolated darkness. You know, big freeze, right. But if this

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<v Speaker 2>new theory holds true, if the universe truly operates via

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<v Speaker 2>a thermodynamic cycle, functioning like a colossal cosmic engine that

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<v Speaker 2>continuously generates matter to fuel its own endless expansion, it

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<v Speaker 2>happens to an engine over time. Even the best design

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<v Speaker 2>car eventually reaches its limit. Does a universe built like

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<v Speaker 2>an engine eventually run out of whatever underlying fuel drives

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<v Speaker 2>the cycle? Does the thermodynamic machinery eventually stall out and

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<v Speaker 2>break down? Or is this cosmic engine perfectly engineered to

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<v Speaker 2>just keep running, generating itself forever