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Speaker 1: Imagine just for a moment, that you were suddenly dropped

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right into the very middle of a pitch black ocean. Oh,

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that is a terrifying thought to start with, right, But

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this isn't a nocean of water on Earth. There is

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absolutely no light, like zero.

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Speaker 2: None, just absolute darkness.

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Speaker 1: Exactly, if you hold your hand up in front of

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your face, there is literally nothing to see. Not a

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single photon of visible light is bouncing off it. Wow.

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There's no concept of up, you know, and no concept

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of down. You have zero sense of movement because there's

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just nothing to move in relation.

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Speaker 2: To I no reference points at all.

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Speaker 1: The silence is absolute. Yeah, it is this ocean of

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pure nothingness, and it stretches out in every conceivable direction

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for hundreds of millions of light years. You are completely

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utterly alone in a bubble of eternal night.

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Speaker 2: It's basically the ultimate sensory deprivation chamber. Yes, I mean,

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if you were floating in that space, the only physical

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interaction you would have with the broader universe would be

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this faint, microscopic bombardment of the cosmic microwave background, you know,

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the after glow of the Big Bang itself, Just.

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Speaker 1: That tiny hiss of radiation.

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Speaker 2: Right beyond that whispering static there are no galaxies, no stars,

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no dust clouds. It's just an unfathomable expanse of emptiness

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that completely defies human comprehension. It really challenges everything we

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think we know about cosmic architecture.

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Speaker 1: Well, welcome to Thrilling Threads. I am so glad you're

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joining us today because our mission for this deep dive

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into this source material is it's pretty simple, but incredibly ambitious.

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We are going to completely shatter your perception of the universe.

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Speaker 2: I love it.

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Speaker 1: Because you know, when you or I look up at

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the night sky, we think of space as this bustling,

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crowded canvas. We picture billions of stars, swirling galaxies, nebulas,

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bursting with radiation and color.

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Speaker 2: Which is a very localized bias really exactly.

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Speaker 1: But today we are exploring and overwhelming, terrifying and frankly

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fascinating truth. The vast majority of our cosmos is actually

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made up of gigantic, unfathomably empty space is known as

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cosmic voids. The nothingness is the rule. It really is

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stuff like the stars, the planets, the literal atoms that

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make up your body, that is the very rare exception.

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Speaker 2: And what's fascinating here is that the scientific consensus has

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fundamentally shifted on this. These empty spaces aren't just passive

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you know, inert rooms.

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Speaker 1: They're not just empty boxes, right.

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Speaker 2: They aren't just missing puzzle pieces or blank spots on

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a map where we just haven't found the galaxies yet.

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These voids are highly dynamic engines of cosmic evolution, weight engines. Yeah,

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they are growing, drifting, and pressing against one another. Inside them,

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the very fabric of space is being stretched, and ultimately,

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these bubbles of nothingness contain the physical mechanisms that will

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decide the fate of the entire observable universe.

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Speaker 1: Okay, let's unpack this because before we can truly appreciate

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the mechanics of that emptiness, we kind of have to

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establish a baseline. Right, We need a sense of scale,

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we do.

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Speaker 2: We need to look at our own neighborhood first, Right,

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Let's look.

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Speaker 1: At the something before we stare into the abyss of

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the nothing.

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Speaker 2: So to comprehend the void, you first have to understand

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the physical scaffolding that borders it. Imagine zooming away from Earth,

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not just in a rocket, but traveling at millions of

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times the speed.

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Speaker 1: Of light, just ripping through the Solar System exactly.

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Speaker 2: You pull back past the Solar System, past the Orion arm,

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until you can see our entire home galaxy, the Milky Way,

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just glowing in its entirety, which is.

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Speaker 1: Staggering all on its own. Yeah. I mean, we are

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looking at a barred spiral galaxy containing roughly two hundred

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billion stars.

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Speaker 2: It's massive, and it's not even isolated.

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Speaker 1: We have dozens of dwarf galaxies like the large and

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small magelantic clouds, and they're caught in our gravitational poll

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basically orbiting us like tiny.

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Speaker 2: Moons, like a swarm of bees.

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Speaker 1: Yeah, it feels incredibly crowded, like a massive metropolitan center.

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And then you look a little further out, about two

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point five million light years away, and there is the

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Andromeda galaxy.

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Speaker 2: And Andromeda is the even more massive than the Milky Way.

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It has its own swarm of satellite galaxies. And it

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is crucial to understand the kinematics here, right, the movement. Yes,

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despite the fact that the universe overall is expanding, the

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Milky Way and Andromeda are gravitationally bound.

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Speaker 1: To each other. Really the expansion isn't pushing us apart.

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Speaker 2: No, because our mutual gravitational pull is strong enough to

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completely overpower the underlying expansion of space. In our local region,

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we are actually hurtling toward each other at roughly one

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hundred and ten kilometers per second.

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Speaker 1: Oh wow, so we're going to hit it.

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Speaker 2: Oh? Absolutely, We're locked on a direct collision course that

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will culminate in a massive galactic merger billions of years

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from now.

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Speaker 1: That's insane, So okay, we keep zooming out to get

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the broader context. We pull back further and see what

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astronomers call the local group. Right, This is our specific

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gravitationally bound pocket of the universe. It's roughly ten million

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light years across, containing over fifty galaxies.

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Speaker 2: And they aren't just floating independently either.

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Speaker 1: No, they're embedded within this massive invisible halo of dark

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matter right exactly.

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Speaker 2: This dark matter acts as the structural foundation. It exerts

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the gravitational force necessary to keep this entire group tethered together.

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It's a hyper connected neighborhood.

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Speaker 1: And because of that gravitational binding, the reality is that

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no human being, and like no probe we ever build,

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will naturally leave this ten million light your pocket.

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Speaker 2: The escape velocity required to break free of the local

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group's collective gravitational well is just immense.

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Speaker 1: It is, for all intents and purposes, a sealed perimeter.

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We are locked in.

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Speaker 2: It is an isolated island in a much larger, highly

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structured archipelago, because if you continue zooming out past our

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local group, you encounter the Virgo supercluster.

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Speaker 1: Okay, now we're talking about the big stuff.

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Speaker 2: Massive stuff. This is a colossal structure containing thousands of

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galaxies spread over roughly one hundred million light years. The

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sheer density of buryonic matter that's the normal matter that

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makes up stars and gas, along with the staggering concentrations

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of dark matter. It creates a gravitational environment of intense

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violence and activity.

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Speaker 1: Just constant churning.

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Speaker 2: Galaxies are continuously stripped of their gas, merging and triggering

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these massive bursts of star formation.

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Speaker 1: And see, this is exactly where I get stuck. This

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is where I have to push back a little on

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the source text narrative about emptiness.

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Speaker 2: Oh, how so, think.

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Speaker 1: About the analogy of moving from a bustling city to

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an absolute wilderness. We live in the cosmic equivalent of

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times square on New Year's Eve.

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Speaker 2: That's a great way to put it right.

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Speaker 1: Our immediate neighborhood is so violently busy that our entire

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galaxy is literally crashing into Andromeda. We have dwarf galaxies

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swarming us. We belong to this tight cluster of fifty galaxies,

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which is part of a massive thousand strong supercluster.

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Speaker 2: It's very chaotic locally exactly.

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Speaker 1: So, if our universe is defined by all these massive superstructures,

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gravitational binding and just constant collisions, how could the universe

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possibly be mostly empty?

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Speaker 2: It seems like a contradiction.

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Speaker 1: It totally does. Yeah, the observational data we have from

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our own backyard seems completely opposed to the idea of

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avoid dominated universe.

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Speaker 2: Well, what's fascinating here is that your intuition perfectly mirrors

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the assumptions of early twentieth century cosmologists.

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Speaker 1: Really, they thought the same thing.

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Speaker 2: Oh absolutely, Before the advent of deep space redshift surveys,

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astronomers operated under a strict interpretation of the cosmological principle,

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which is what exactly it's the idea that on a

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large enough scale, the universe is homogeneous and isotropic. They

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assumed that if you zoomed out far enough, the universe

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would look like a smooth, uniform soup of galaxies spread

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relatively evenly in all directions.

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Speaker 1: Right, it made intuitive sense based on the local clustering

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we could observe. Like if you take a cup of

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water from the ocean and it's full of salt and plankton,

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you naturally assume the rest of the ocean is made

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of the exact same composition.

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Speaker 2: Exactly. If we see galaxies everywhere around us, we naturally

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assume the universe is just an endless, relatively uniform sea

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of galaxies.

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Speaker 1: What broke that assumption?

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Speaker 2: The paradigm shift really occurred in the late nineteen seventies

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and eighties. It was driven by researchers like Margaret Geller

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and John Houtra at the Harvard Smithsonian Center for Astrophysics.

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Speaker 1: Oh right, they did the big mapping project.

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Speaker 2: They did. They didn't just look at the two D

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positions of galaxies in the sky. They measured their red shift.

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Speaker 1: Okay, explain redshift for us really quick.

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Speaker 2: Sure, as the universe expands, the light from distant galaxies

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is physically stretched into longer, redder wavelengths by measuring that

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red shift, astronomers could calculate exactly how fast a galaxy

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is moving away from.

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Speaker 1: Us, and because of Hubble's law, that speed tells.

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Speaker 2: Us the distance precisely, it tells us exactly how far

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away it is. This allowed them to map the universe

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in three dimensions for the very first time, and what.

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Speaker 1: They found completely broke the smooth soup model.

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Speaker 2: It dismantled it entirely. When you plot the three D

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positions of millions of galaxies, you don't see an even distribution,

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not at all. You see a highly complex, interconnected structure

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that we now call the cosmic web.

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Speaker 1: The cosmic web. It sounds like a sci fi movie, it.

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Speaker 2: Really does, but the universe looks remarkably like a three

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dimensional spider web, or like the neural pathways in a

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human brain.

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Speaker 1: This is these glowing threads everywhere.

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Speaker 2: Right, you have these incredibly long, dense filaments. These are

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massive threads of dark matter and intergalactic gas studded with

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thousands of galaxies. And where these cosmic filaments intersect, they

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form massive dense knots.

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Speaker 1: And those knots of the superclusters.

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Speaker 2: Exactly like the Virgo supercluster. We reside in.

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Speaker 1: Okay, let's just pause and internalize that. Ye, our entire

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local group, this massive ten million light year expanse, containing

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the Milky Way, Andromeda, fifty other galaxies, and literally all

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of our future human destiny, all right there in the

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grand scheme of the cosmic web. We are just a

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micro scopic speck clinging to one single thread. We are

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locked inside this pocket, woven into a dark matter scaffold,

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and it's the absolute limit of our physical reality.

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Speaker 2: It provides a deeply humbling perspective. But to truly grasp

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the architecture of the universe, you have to look at

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what isn't there.

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Speaker 1: Okay, you've got my attention.

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Speaker 2: Think about a spider web again. While the structural integrity

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comes from the silk threads, the actual volume of the

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web is almost entirely composed of the empty air between

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those threads. Oh wow, Yeah, Without the empty gaps, it

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isn't a web. It's just a solid block of silk.

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Speaker 1: Right. The negative space defines the structure exactly.

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Speaker 2: The cosmic web operates on the same geometric principle. The

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glowing filaments and dense superclusters are just the incredibly thin

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borders the vast, overwhelming majority of the physical volume of

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the universe, roughly eighty percent of it is found in

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the enormous dark gaps between the threads.

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Speaker 1: So that takes us right back to our journey. We've

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zoomed out past the Milky Way, the local group, and

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we are standing on the very edge of the Virgo supercluster.

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We are basically standing on the edge of the thread. Yes,

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and right over the edge of this incredibly dense, violent

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filament is the gap.

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Speaker 2: You have reached, the cosmic cliff. Right at the boundary

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of the Virgo supercluster, the density of matter just drops

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off a precipice. You were staring into a region known

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as the local void.

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Speaker 1: The local Void. Yeah, just the name alone gives me chills.

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Speaker 2: It's quite literal.

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Speaker 1: We're looking at an empty bubble of space that spans

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roughly two hundred million light years across. Let me try

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to conceptualize that physical distance.

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Speaker 2: It's almost impossible for the human brain to picture.

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Speaker 1: Right light, the fastest thing in the universe, traveling at

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three hundred thousand kilometers per second, takes two hundred million

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years just across from one side of this empty room

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to the other.

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Speaker 2: That's a long time to travel through nothing.

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Speaker 1: If this void we're a bright, glowing object instead of

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absolute darkness, it would take up a massive portion of

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our night sky on Earth. But instead it's just nothing.

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Speaker 2: And you know, mapping the local void has been notoriously

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difficult for astrophysicists. A large portion of it lies behind

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the Milky Way's galactic center.

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Speaker 1: Oh so our own galaxies blocking the view exactly.

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Speaker 2: It's a region heavily obscured by dust and gas, known

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as the zone of avoidance. We can't easily see through

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our own galaxy using visible.

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Speaker 1: Lights, So how do we know it's there?

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Speaker 2: Well, by utilizing radio and infrared astronomy, and by carefully

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measuring the peculiar velocities of galaxies that is, how they

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are moving independent of the universe's baseline expansion, we can

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infer the void's immense size and influence.

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Speaker 1: Wait explain that peculiar velocity measurement. How does treking the

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movement of a galaxy tell us there's an invisible empty

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space behind our own galaxy.

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Speaker 2: It comes down to gravitational vectors. When astronomers map the

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motion of galaxies in our local universe, they notice that we,

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along with our neighboring galaxies aren't just drifting randomly, okay,

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We are actively streaming in a specific direction. We are

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being pulled toward a massive concentration of mass known as

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the Great attractor.

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Speaker 1: All right, the great Attractor, I've heard of that.

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Speaker 2: But that pull only accounts for about half of our velocity.

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The other half of our speed comes from the fact

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that we are being powerfully repelled away from the local void.

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Speaker 1: Hold on, I need to push back on the word repel. Okay,

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fair enough, because we just established that voids are incredibly empty.

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They don't have mass. If gravity is the attraction between masses,

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how can an empty space repel anything. It doesn't have

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a force field.

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Speaker 2: That is the crucial mechanical paradox of cosmic voids. You

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are absolutely correct. Voids do not possess a repulsive force field.

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Speaker 1: Okay, so what's happening.

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Speaker 2: The repulsion is actually a relative effect of uneven gravity.

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Let me give you an analogy. Imagine you are standing

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in the exact center of a perfectly spherical room, and

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all the walls have the exact same mass.

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Speaker 1: Right, I'm in the room.

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Speaker 2: The gravitational pull on you from all directions is equal

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so you stay perfect still in the center. But what

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happens if someone removes the entire left wall.

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Speaker 1: Well, suddenly there's no mass pulling me to the left,

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but the right wall is still there, so it's gravity

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takes over and I get dragged to the right.

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Speaker 2: Precisely, the empty space where the left wall used to

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be didn't push you. It simply stopped pulling.

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Speaker 1: Oh wow.

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Speaker 2: Because a void lacks mass, it exerts almost zero gravitational pull. Meanwhile,

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the incredibly dense filaments and superclusters surrounding the void have

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immense gravitational.

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Speaker 1: Power, so matter drains out of the.

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Speaker 2: Voids exactly, it gets pulled toward the dense walls. The

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local void isn't actively pushing the Milky Way. Rather, the

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lack of mass behind us means there is nothing balancing

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the massive gravitational pull of the structures ahead of us.

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We are falling away from the emptiness.

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Speaker 1: That is a brilliant way to conceptualize it. It's like

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a reverse black hole.

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Speaker 2: That's a very apt comparison with.

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Speaker 1: A black hole. You have a singularity in the center

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with so much mass that its gravity pulls everything inside

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and nothing can escape. Is the exact opposite. It's an

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area with absolutely zero mass in the center surrounded by

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an edge with unimaginable mass. So instead of everything falling in,

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everything falls out.

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Speaker 2: And this drainage system is a compounding, accelerating process. It

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is a fundamental feature of cosmic evolution, driven by gravitational instability.

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Speaker 1: How So, like it feeds itself.

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Speaker 2: Yes, the emptier avoid gets the less mass it has,

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the less mass it has, the weaker its gravitational pull becomes. Meanwhile,

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the matter that was drained to the edges makes the

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superclusters even denser, increasing their gravitational dominance.

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Speaker 1: Like a tug of war where one side isn't even.

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Speaker 2: Trying exactly over billions of years, it is a system

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where the dense regions get denser and the empty regions

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get emptier, the rich get richer, and the poor get poorer.

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Speaker 1: Okay, if the local void is just the appetizer, let's

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jump to the main course. We've talked about our neighboring emptiness.

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But let's travel towards the greatest, most profound expanse of

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nothing we have ever documented. Let's dive right into the

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Booths supervoid.

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Speaker 2: Oh, the Booth supervoid. It is a true anomaly of scale.

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It was discovered in nineteen eighty one by Robert Kushner

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and his colleagues during a red shift survey of the

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Boots constellation.

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Speaker 1: Just looking at a patch of sky and finding absolutely nothing.

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Speaker 2: Quite literally, it is a nearly spherical region of space

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spanning an astonishing three hundred and thirty million light years

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in diameter.

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Speaker 1: Three hundred and thirty million.

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Speaker 2: Yes, and to put the statistical improbability of this structure

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into perspective, based on the average density of the universe,

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a volume of space that large should theoretically contain over

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two thousand massive galaxies, but it doesn't.

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Speaker 1: At last count, astronomers have found roughly sixty galaxies scattered

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throughout that massive three hundred and thirty million light year expanse.

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It is a total cosmic desert.

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Speaker 2: It is functionally empty.

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Speaker 1: And this brings me back to the thought experiment we

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started with. Put yourself in the dead center of the

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boat supervoid. Imagine teleporting a human being in a spacesuit

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right into the middle of that desert.

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Speaker 2: It would be profoundly disturbing.

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Speaker 1: You are surrounded by a darkness so perfect, so absolute,

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that the human mind can barely process the sensory deprivation.

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You look up down, left right, there is not a

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single photon of light reaching your eyes from any distant star,

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because the nearest star is over one hundred and fifty

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million light years away.

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Speaker 2: From a purely observational standpoint, without highly specialized equipment designed

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to detect deep infrared or radio waves, the universe would

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appear to consist solely of yourself.

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Speaker 1: It would be terrifying. You wouldn't just feel alone, you

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would feel like reality itself had ceased to exist. There

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is not a single visual indicator that an outside universe

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is out there. It honestly brings up this intense feeling

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of existential dread.

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Speaker 2: I can see why.

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Speaker 1: Think about the trajectory of human history. If Earth had

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somehow formed in the center of the Boots supervoid instead

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of in the Milky Way's bustling neighborhood, our entire unders

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standing a reality would be fundamentally different. How do you mean, Well,

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if you looked up into the sky from a planet

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in the middle of Boots, you would see the stars

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of your own isolated galaxy, and beyond that just an

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endless black wall. We would have naturally assumed that our

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single galaxy was the entire universe.

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Speaker 2: Ah, yes, because there would mean no visible evidence to

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the contrary, Right.

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Speaker 1: We wouldn't have even conceptualized that other galaxies existed until

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the late twentieth century when we invented highly advanced orbital telescopes.

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For thousands of years of human philosophy and science, we

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would have been convinced we were entirely alone in an

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endless dark room.

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Speaker 2: While that thought experiment feels isolating to us, you know,

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the mathematics of the cosmos suggest a different perspective. Really,

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how so, we viewed the densely packed, highly interactive environment

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of the Milky Way as normal because it produced us,

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But volumetrically speaking, our crowded neighborhood is the freak occurrence.

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Speaker 1: We are the weird ones.

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Speaker 2: Exactly. To an objective observer looking at the universe as

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a whole, that silent, perfectly black, motionless environment of the

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Boutet supervoid is the standard state of the universe.

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Speaker 1: Okay, So the mechanics of voids dictate that matter drains

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outward toward the dense filaments. It's an incredibly efficient sorting mechanism.

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But as we look at the dynamic nature of the

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cosmic web, where galaxies are constantly in motion, moving at

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millions of kilometers an hour, orbiting and crashing into each other.

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Why don't galaxies accidentally fly into the voids.

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Speaker 2: That's a very logical question.

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Speaker 1: If you have a crowded room of people running around randomly,

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eventually people are going to spill out into the empty hallway.

397
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Why don't rogue galaxies just shoot off the filaments and

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gradually fill up these voids over the course of billions

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of years.

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Speaker 2: Because the fluid dynamics of the universe prevent that from happening.

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00:19:47,839 --> 00:19:49,759
You have to look at the mathematical models of how

402
00:19:49,880 --> 00:19:52,000
voids expand, like the Zildavich approximation.

403
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Speaker 1: Okay, tell me about that.

404
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Speaker 2: The cosmic web isn't static. The voids themselves are expanding,

405
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pushing outward. The visual announ aloga, often cited in hydrodynamical simulations,

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is that galaxies cling to the edges of voids like

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reflections of light on soap bubbles.

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Speaker 1: I love the soap bubble analogy. Let's expand on that

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00:20:10,039 --> 00:20:12,640
because it's a great functional way to picture this. When

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00:20:12,640 --> 00:20:16,079
you blow a bubble, all the soapy water is trapped

411
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in that incredibly thin, high surface tension film on the outside,

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while the inside is just empty air.

413
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Speaker 2: Exactly.

414
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Speaker 1: The water doesn't drift into the center of the bubble.

415
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It is locked to the edge, and as the bubble expands,

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the film gets thinner and thinner, but the water stays

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on the surface.

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Speaker 2: The physics underlying the cosmic version of that bubble involves

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the interplay between the expansion of space and local gravitational collapse.

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As a void expands, it essentially acts as a massive

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spherical under density. It presses outward against the surrounding matter.

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Speaker 1: So the bubbles are pushing against each other.

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Speaker 2: Yes, when two expanding voids press against each other, the

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matter caught between them is squeezed into a flat sheet

425
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or a pancake of dark matter and gas. As multiple

426
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voids expand and press together from different angles, these sheets

427
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intersect to form filaments, and the filaments intersect to form

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dense nodes.

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Speaker 1: So the whole web is just the boundaries of expanding

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bubbles exactly.

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Speaker 2: A galaxy wandering into a void is physically opposed by

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the outward flow of the void's expansion and the intense

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gravitational pull of the wall it just left to enter

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a void, a galaxy would have to fight against the

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primary structural currents of the universe.

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Speaker 1: It's like trying to paddle a canoe up of violently

437
00:21:31,000 --> 00:21:34,279
flowing waterfall. The physics of the environment just drag you

438
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back down to the dense space. But wait, what if

439
00:21:37,400 --> 00:21:39,240
we didn't wait for nature to do it? What do

440
00:21:39,279 --> 00:21:42,279
you mean, what if we bypass the natural gravitational currents.

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It's say a highly advanced Type three civilization built an

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incredible propulsion system and intentionally forced its way off the

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cosmic web, aiming straight for the darkest place in the universe.

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Could we physically enter avoid Is there a literal barrier?

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Speaker 2: No, there is no physical barrier. The space inside a

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void is structually the exact same space time continuum as

447
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the space.

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Speaker 1: Here, so we could just fly in.

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Speaker 2: Technically, yes, The primary engineering challenge wouldn't be surviving the

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00:22:10,880 --> 00:22:14,839
void itself. The challenge is achieving the massive escape velocity

451
00:22:14,880 --> 00:22:17,960
required to break free from the deep gravitational well of

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your home supercluster.

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Speaker 1: Which would take an unimaginable amount of energy.

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Speaker 2: Precisely, once you overcome that intense initial drag, you could

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theoretically coast into the emptiness. But From an astrophysical perspective,

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the question isn't whether you could do it, but why

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you would expend the energy to do so. You are

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traversing hundreds of millions of light years to visit a

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region defined by its lack of material resources.

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Speaker 1: Because there's nothing there. But honestly, when I dug into

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the research on this, my mind instantly went to an

462
00:22:46,920 --> 00:22:49,160
incredibly cool science fiction premise.

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Speaker 2: Oh, let's hear it.

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Speaker 1: Why would a civilization need to travel into a cosmic

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void to hide?

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Speaker 2: Oh, a cosmic refuge exactly.

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Speaker 1: Think about life on the cosmic web. The environment inside

468
00:23:01,599 --> 00:23:06,240
a massive cluster like Virgo is incredibly violent. Galaxies are

469
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constantly colliding. Supermassive black holes are actively feeding firing off

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jets of relativistic particles.

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Speaker 2: It is a high radiation environment.

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Speaker 1: Yes, the immense gravity of neighboring galaxies is constantly warping

473
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solar systems, triggering massive bursts of star formation that inevitably

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lead to localized ways of deadly supernovas that floods whole

475
00:23:27,160 --> 00:23:31,160
regions with lethal gamma radiation. Living on the cosmic web

476
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is like trying to build a house in an active

477
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war zone.

478
00:23:33,920 --> 00:23:36,960
Speaker 2: That is a very apt description of cluster kinematics.

479
00:23:37,079 --> 00:23:39,559
Speaker 1: So if you were a highly advanced civilization and you

480
00:23:39,599 --> 00:23:42,359
saw the universe slowly grinding itself down in these violent,

481
00:23:42,440 --> 00:23:45,359
high energy collisions, you might look at that perfectly empty,

482
00:23:45,359 --> 00:23:48,759
perfectly silent void and think that is the ultimate cosmic

483
00:23:48,799 --> 00:23:49,279
panic room.

484
00:23:49,920 --> 00:23:52,839
Speaker 2: The concept of a void as a refuge is fascinating

485
00:23:52,839 --> 00:23:55,640
when you consider the long term habitability of the universe,

486
00:23:56,039 --> 00:23:58,519
and you know, if a civilization did manage to penetrate

487
00:23:58,519 --> 00:24:01,079
the deep Void, they would find that it isn't completely

488
00:24:01,200 --> 00:24:04,240
devoid of resources. It is a desert, but even deserts

489
00:24:04,279 --> 00:24:05,480
have micro ecosystems.

490
00:24:05,720 --> 00:24:07,960
Speaker 1: Wait, I thought the whole point was that all the

491
00:24:08,000 --> 00:24:10,839
matter drained out to the edges. What's left inside well.

492
00:24:10,920 --> 00:24:14,640
Speaker 2: High resolution and body simulations like the Millennium Run, which

493
00:24:14,759 --> 00:24:18,400
model the distribution of dark matter across cosmic history, reveal

494
00:24:18,480 --> 00:24:20,279
that voids are not perfectly clean.

495
00:24:20,640 --> 00:24:22,240
Speaker 1: So there is some stuff floating around.

496
00:24:22,480 --> 00:24:24,880
Speaker 2: Yes, While the vast majority of matter is swept to

497
00:24:24,920 --> 00:24:29,240
the walls, extremely faint, delicate tendrils of dark matter remain

498
00:24:29,319 --> 00:24:30,599
inside the voids.

499
00:24:30,599 --> 00:24:31,559
Speaker 1: Like little cobwebs.

500
00:24:31,680 --> 00:24:36,359
Speaker 2: Exactly, They crisscross the darkness like microscopic threads of mycelium

501
00:24:36,440 --> 00:24:39,440
growing in a dark cave. They are a much thinner,

502
00:24:39,640 --> 00:24:43,000
more diffuse echo of the massive dark matter filaments that

503
00:24:43,039 --> 00:24:46,279
make up the primary cosmic web. And if you follow

504
00:24:46,319 --> 00:24:48,960
these faint tendrils deep into the void, where the dark

505
00:24:49,000 --> 00:24:51,799
matter density is just barely high enough to attract a

506
00:24:51,799 --> 00:24:55,359
halo of hydrogen gas, you find something truly remarkable.

507
00:24:55,519 --> 00:24:56,599
Speaker 1: The void galaxy.

508
00:24:56,720 --> 00:25:00,000
Speaker 2: Yes, suspended in this massive ocean of darkness are incredible

509
00:25:00,319 --> 00:25:04,400
faint isolated galaxies. They are the absolute rarest classification of

510
00:25:04,400 --> 00:25:07,480
galaxies we have identified. They are completely cut off from

511
00:25:07,480 --> 00:25:09,839
the rest of the universe, existing in a state of

512
00:25:09,960 --> 00:25:12,119
profound astronomical isolation.

513
00:25:12,599 --> 00:25:16,920
Speaker 1: So mechanically, how is avoid galaxy different from a galaxy

514
00:25:16,960 --> 00:25:20,200
like our Milky Way? Because they don't have neighbors constantly

515
00:25:20,240 --> 00:25:23,160
tugging at them. They aren't engaged in that constant cosmic

516
00:25:23,200 --> 00:25:27,000
warfare we just talked about. How does that isolation change

517
00:25:27,039 --> 00:25:28,119
their physical evolution?

518
00:25:28,319 --> 00:25:33,359
Speaker 2: It alters their evolutionary timeline entirely. In a crowded cluster environment,

519
00:25:33,480 --> 00:25:37,480
the gravitational interference from neighboring galaxies, what we call tidal forces,

520
00:25:37,960 --> 00:25:40,880
constantly churns up the intergalactic.

521
00:25:40,160 --> 00:25:42,400
Speaker 1: Gas right the war zone effect exactly.

522
00:25:42,519 --> 00:25:46,720
Speaker 2: This triggers explosive rapid periods of star formation called starbursts.

523
00:25:47,119 --> 00:25:51,039
But these interactions also violently strip galaxies of their remaining gas,

524
00:25:51,079 --> 00:25:53,079
a process known as ram pressure stripping.

525
00:25:53,200 --> 00:25:55,039
Speaker 1: So they just lose all their shoel they do.

526
00:25:55,160 --> 00:25:58,759
Speaker 2: It's a live, fast, die young life cycle. The galaxy

527
00:25:58,799 --> 00:26:02,440
burns through its star format material incredibly quickly and eventually

528
00:26:02,480 --> 00:26:06,279
transitions into a red and dead elliptical galaxy full of

529
00:26:06,319 --> 00:26:08,519
aging stars with no new ones being born.

530
00:26:08,720 --> 00:26:12,079
Speaker 1: But avoid galaxy doesn't experience any of that tidal trauma.

531
00:26:12,200 --> 00:26:14,920
Speaker 2: No, they don't. They exist in a state of undisturbed

532
00:26:14,960 --> 00:26:18,720
equilibrium because they have no neighbors to violently strip their

533
00:26:18,720 --> 00:26:23,599
gas or disturb their rotational structure. They accrete pristine, unpolluted

534
00:26:23,640 --> 00:26:28,440
hydrogen gas from the surrounding innergalactic medium at an incredibly slow,

535
00:26:28,720 --> 00:26:29,440
steady rate.

536
00:26:29,640 --> 00:26:31,160
Speaker 1: Do they just sip their fuel instead of.

537
00:26:31,200 --> 00:26:35,559
Speaker 2: Checking it exactly. As a result, void galaxies are typically smaller,

538
00:26:36,119 --> 00:26:39,839
retain a distinct bluish hue, and are absolutely saturated with

539
00:26:39,960 --> 00:26:41,279
raw star forming fuel.

540
00:26:41,640 --> 00:26:44,400
Speaker 1: Let's break down the color difference. Why does slow star

541
00:26:44,480 --> 00:26:48,000
formation make them look blue while the older cluster galaxies

542
00:26:48,000 --> 00:26:48,519
look red?

543
00:26:48,759 --> 00:26:51,160
Speaker 2: The color of a galaxy is a direct indicator of

544
00:26:51,200 --> 00:26:55,440
its stellar demographics. Hot massive young stars, specifically O n

545
00:26:55,559 --> 00:26:58,599
B type stars burn incredibly bright and emit primarily in

546
00:26:58,640 --> 00:27:02,880
the blue and ultraviolet spec Because of void galaxies continuously

547
00:27:03,000 --> 00:27:06,240
gently forming new stars, it is always populated by these

548
00:27:06,279 --> 00:27:09,759
bright blue giants and a crowded cluster galaxy that has

549
00:27:09,799 --> 00:27:13,559
had its gas stripped away, star formation ceases.

550
00:27:13,240 --> 00:27:15,079
Speaker 1: And the blue stars burn out right.

551
00:27:15,480 --> 00:27:18,359
Speaker 2: The massive blue stars burn out and die quickly, leaving

552
00:27:18,400 --> 00:27:23,119
only the smaller, cooler, longer lived red dwarf stars. Furthermore,

553
00:27:23,279 --> 00:27:26,519
void galaxies lack the heavy concentrations of cosmic dusts that

554
00:27:26,559 --> 00:27:29,839
accumulate in highly active galaxies, so the blue light from

555
00:27:29,880 --> 00:27:34,319
their young stars isn't obscured their pristine glowing blue beacons

556
00:27:34,359 --> 00:27:34,880
in the dark.

557
00:27:35,039 --> 00:27:38,720
Speaker 1: So, going back to my alien panic room theory, avoid

558
00:27:38,759 --> 00:27:41,839
galaxy is essentially preserving its fuel while the rest of

559
00:27:41,880 --> 00:27:45,200
the universe violently burns through its supply. If you are

560
00:27:45,240 --> 00:27:47,880
a civilization trying to outlive the natural life span of

561
00:27:47,920 --> 00:27:51,160
the cosmos, avoid galaxy is precisely where you want to be.

562
00:27:51,359 --> 00:27:54,839
Speaker 2: It is the most strategic location for long term survival.

563
00:27:54,519 --> 00:27:57,799
Speaker 1: Right as the trillions of years tick by. The crowded

564
00:27:57,839 --> 00:28:00,759
galaxies on the cosmic web are going to exhaust their resources.

565
00:28:00,799 --> 00:28:02,799
They will use up all their hydrogen, their stars will

566
00:28:02,839 --> 00:28:06,599
die off, and those massive glowing superclusters will go completely dark.

567
00:28:06,799 --> 00:28:08,880
Speaker 2: That is the inevitable thermodynamic fate.

568
00:28:09,039 --> 00:28:12,680
Speaker 1: But these isolated little blue fireflies, these void galaxies, will

569
00:28:12,680 --> 00:28:16,519
still be slowly, calmly churning out new stars. They are

570
00:28:16,559 --> 00:28:19,039
hoarding the life giving resources of the universe.

571
00:28:19,359 --> 00:28:22,920
Speaker 2: The astrophysics of their isolation leads to a deeply profound

572
00:28:22,960 --> 00:28:27,400
projection regarding the distant future. Because void galaxies are hoarding

573
00:28:27,400 --> 00:28:30,519
their primordial gas and aging in slow motion, it is

574
00:28:30,599 --> 00:28:33,720
highly probable that as the universe enters the degenerate era,

575
00:28:34,240 --> 00:28:37,559
the phase when star formation across the cosmos largely ceases,

576
00:28:38,119 --> 00:28:41,240
these isolated islands will be the very last bastions of

577
00:28:41,279 --> 00:28:45,599
stellar ignition. Billions upon billions of years after the Milky

578
00:28:45,599 --> 00:28:49,000
Way has gone dark, a void galaxy will still be glowing.

579
00:28:49,720 --> 00:28:52,359
It is statistically likely that the very last star to

580
00:28:52,440 --> 00:28:54,960
ever shine in our universe will be born and will

581
00:28:55,000 --> 00:28:57,720
eventually die deep inside a cosmic void.

582
00:28:58,039 --> 00:29:00,279
Speaker 1: The last light in the universe will be surrounded by

583
00:29:00,279 --> 00:29:04,799
the greatest darkness as incredibly poetic. It frames these terrifying

584
00:29:04,839 --> 00:29:08,160
empty spaces not as dead zones, but as the ultimate

585
00:29:08,200 --> 00:29:12,440
safe havens, the final sanctuaries for light and potentially for life.

586
00:29:12,559 --> 00:29:14,880
Speaker 2: They certainly act as time capsules. But before we get

587
00:29:14,880 --> 00:29:18,319
too comfortable characterizing voids as peaceful sanctuaries, we have to

588
00:29:18,359 --> 00:29:20,920
look at the underlying cosmology that governs their future.

589
00:29:21,039 --> 00:29:22,319
Speaker 1: Oh there's a catch.

590
00:29:22,480 --> 00:29:25,440
Speaker 2: There is always a catch, because while the moids themselves

591
00:29:25,480 --> 00:29:29,359
are practically empty of matter, they are completely saturated with

592
00:29:29,400 --> 00:29:31,960
a force that makes them the most dangerous regions in

593
00:29:32,000 --> 00:29:34,279
the universe on a cosmological timeline.

594
00:29:34,359 --> 00:29:35,559
Speaker 1: Okay, I'm listening.

595
00:29:35,400 --> 00:29:37,960
Speaker 2: A force that guarantees that the piece of the void

596
00:29:38,000 --> 00:29:39,920
galaxy is ultimately temporary.

597
00:29:40,559 --> 00:29:42,720
Speaker 1: We are talking about dark energy. We are.

598
00:29:43,200 --> 00:29:47,240
Speaker 2: Dark energy is arguably the most profound, unresolved mystery in

599
00:29:47,319 --> 00:29:52,640
modern theoretical physics. It is an unseen, poorly understood phenomenon

600
00:29:52,880 --> 00:29:57,359
often modeled mathematically as a cosmological consonant or lambda, that

601
00:29:57,519 --> 00:30:01,160
is actively driving the accelerated expansion of the universe. Right,

602
00:30:01,240 --> 00:30:04,200
it is the mechanism that will ultimately dismantle the cosmos.

603
00:30:04,559 --> 00:30:06,720
Speaker 1: Dark energy is one of those concepts that sounds like

604
00:30:06,839 --> 00:30:10,680
absolute magic until you dig into the physics. If this

605
00:30:10,960 --> 00:30:13,519
energy is a property of space itself, and it is

606
00:30:13,599 --> 00:30:17,359
everywhere actively pushing the universe apart, why don't I feel

607
00:30:17,359 --> 00:30:17,960
it right now?

608
00:30:18,079 --> 00:30:19,440
Speaker 2: That's a common point of confusion.

609
00:30:19,680 --> 00:30:22,440
Speaker 1: Why isn't dark energy pushing the Earth away from the Sun.

610
00:30:22,599 --> 00:30:25,000
If the universe is expanding, why aren't the atoms in

611
00:30:25,039 --> 00:30:26,240
my body flying apart?

612
00:30:26,440 --> 00:30:31,000
Speaker 2: That touches on the critical concept of scale dependence in cosmology.

613
00:30:31,880 --> 00:30:37,359
Dark energy is everywhere, permeating every cubic centimeter of space. However,

614
00:30:37,519 --> 00:30:41,319
its energy density is incredibly low. It's very weak locally,

615
00:30:41,480 --> 00:30:45,279
exactly on a localized scale, like inside a solar system

616
00:30:45,640 --> 00:30:49,559
or even within a massive galaxy cluster. The fundamental forces

617
00:30:49,559 --> 00:30:54,279
of nature completely overpower it. The electromagnetic force holds your

618
00:30:54,319 --> 00:30:58,119
atoms together, the gravitational force holds the Earth to the Sun,

619
00:30:58,559 --> 00:31:01,319
and gravity binds them Milky Way to Andromeda.

620
00:31:01,480 --> 00:31:03,920
Speaker 1: So gravity just beats it in an arm wrestling match.

621
00:31:04,039 --> 00:31:08,119
Speaker 2: Yes, these local binding forces are orders of magnitude stronger

622
00:31:08,160 --> 00:31:10,640
than the repulsive push of dark energy. We cannot observe

623
00:31:10,720 --> 00:31:14,279
dark energy doing anything inside our local neighborhood because gravity

624
00:31:14,400 --> 00:31:17,279
is the absolute dominant force in a high density environment.

625
00:31:17,720 --> 00:31:19,960
Speaker 1: So dark energy is a weak pusher, but a very

626
00:31:20,000 --> 00:31:23,599
persistent one. It only wins if there's no gravity fighting back,

627
00:31:23,960 --> 00:31:25,319
which brings us right back to the voids.

628
00:31:25,440 --> 00:31:26,279
Speaker 2: You see the connection.

629
00:31:26,400 --> 00:31:28,440
Speaker 1: If you go into the Benuth supervoid, where there is

630
00:31:28,519 --> 00:31:30,759
virtually zero mass, there is virtually zero.

631
00:31:30,559 --> 00:31:35,240
Speaker 2: Gravity exactly inside the voids. Gravity is so incredibly weak

632
00:31:35,240 --> 00:31:39,400
that it offers no resistance. Here in the absolute nothingness,

633
00:31:39,720 --> 00:31:44,079
dark energy is entirely unopposed. It dominates the physical environment.

634
00:31:44,680 --> 00:31:47,160
As a result, the voids are the primary engines of

635
00:31:47,240 --> 00:31:51,200
cosmic acceleration. Inside the voids is where space itself is

636
00:31:51,240 --> 00:31:52,319
stretching violently.

637
00:31:52,519 --> 00:31:55,039
Speaker 1: Okay, but how do we actually know that? Because we

638
00:31:55,119 --> 00:31:58,519
can't physically see dark energy, and the void is empty,

639
00:31:58,680 --> 00:32:02,839
so we can't see the void directly, how do astrophysicists

640
00:32:02,880 --> 00:32:06,119
actually measure the effect of dark energy inside a void.

641
00:32:06,200 --> 00:32:09,039
Speaker 2: We measure it through an incredibly subtle phenomenon known as

642
00:32:09,039 --> 00:32:11,279
the late time integrated sax Wolf.

643
00:32:11,000 --> 00:32:13,759
Speaker 1: Effect the sax Wolf effect. Okay, break that down for us.

644
00:32:14,039 --> 00:32:17,000
Speaker 2: It involves tracking photons from the cosmic microwave background as

645
00:32:17,039 --> 00:32:19,920
they travel across the universe to reach our telescopes. When

646
00:32:19,920 --> 00:32:23,440
a CMB photon enters a massive supercluster, it falls into

647
00:32:23,440 --> 00:32:25,599
a gravitational well, gaining energy.

648
00:32:25,400 --> 00:32:26,160
Speaker 1: Rolling down a hill.

649
00:32:26,279 --> 00:32:29,079
Speaker 2: Exactly when it climbs back out of the cluster, it

650
00:32:29,160 --> 00:32:31,759
loses that energy. In a static universe, this would be

651
00:32:31,799 --> 00:32:34,400
a zero sum game. The photon leaves with the exact

652
00:32:34,440 --> 00:32:35,559
same energy it entered with.

653
00:32:35,920 --> 00:32:39,759
Speaker 1: But the universe isn't static. Space is expanding while the

654
00:32:39,839 --> 00:32:40,480
photon is.

655
00:32:40,440 --> 00:32:43,640
Speaker 2: Moving precisely, and this is where the voids provide the

656
00:32:43,680 --> 00:32:47,240
proof of dark energy. When a photon enters a massive,

657
00:32:47,359 --> 00:32:50,119
expanding void, it has to climb out of an ever

658
00:32:50,200 --> 00:32:51,759
shallow gravitational environment.

659
00:32:52,079 --> 00:32:53,599
Speaker 1: Wait, why is it getting shallower?

660
00:32:54,359 --> 00:32:57,400
Speaker 2: Because dark energy is actively stretching the void while the

661
00:32:57,480 --> 00:33:00,559
photon is inside it, the physical dimensions of the void

662
00:33:00,680 --> 00:33:04,519
change before the photon can exit. The photon actually loses

663
00:33:04,680 --> 00:33:06,160
energy crossing the void.

664
00:33:06,359 --> 00:33:09,000
Speaker 1: Oh wow, so we can read that energy loss.

665
00:33:09,039 --> 00:33:12,599
Speaker 2: We can By looking at tiny temperature fluctuations in the

666
00:33:12,640 --> 00:33:16,319
CMB and correlating them with the locations of massive voids.

667
00:33:16,559 --> 00:33:19,559
We can physically measure the exact rate at which dark

668
00:33:19,680 --> 00:33:21,759
energy is stretching the nothingness.

669
00:33:21,960 --> 00:33:24,720
Speaker 1: So the voids aren't just sitting there, they are actively

670
00:33:24,799 --> 00:33:28,119
inflating like balloons being pumped full of air, but the

671
00:33:28,160 --> 00:33:30,839
air is the intrinsic energy of the vacuum itself.

672
00:33:31,079 --> 00:33:32,599
Speaker 2: That's a perfect visualization.

673
00:33:32,880 --> 00:33:35,240
Speaker 1: And because there is no matter to generate gravity and

674
00:33:35,240 --> 00:33:38,319
stop the expansion, they just keep blowing up, getting bigger

675
00:33:38,359 --> 00:33:39,839
and bigger and accelerating rate.

676
00:33:40,079 --> 00:33:42,839
Speaker 2: Yes, and as we established earlier, the borders of these

677
00:33:42,880 --> 00:33:46,640
inflating bubbles are the cosmic web, the dense filaments of

678
00:33:46,720 --> 00:33:50,720
dark matter and superclusters where all the galaxies reside. As

679
00:33:50,720 --> 00:33:55,440
the voids inflate, they push outward, applying immense, relentless pressure

680
00:33:55,759 --> 00:33:57,079
to the very architecture of the.

681
00:33:57,119 --> 00:34:01,559
Speaker 1: Universe, which means that nothing is actively attacking the something.

682
00:34:02,200 --> 00:34:05,200
The empty space is physically dismantling the structures of matter.

683
00:34:05,400 --> 00:34:08,800
Speaker 2: That is the grim mechanical reality of the cosmos. As

684
00:34:08,800 --> 00:34:12,239
the voids grow larger and larger, propelled by dark energy,

685
00:34:12,719 --> 00:34:16,519
they encroach upon the filaments. The delicate galaxy clusters are

686
00:34:16,559 --> 00:34:19,719
slowly being stretched and pulled apart by the expansion of

687
00:34:19,760 --> 00:34:21,039
the voids around.

688
00:34:20,719 --> 00:34:23,039
Speaker 1: Them, just ripping the web apart exactly.

689
00:34:23,239 --> 00:34:27,519
Speaker 2: Imagine a massive, dense wall of thousands of galaxies as

690
00:34:27,519 --> 00:34:29,960
the void bubble on either side expands against it. The

691
00:34:30,000 --> 00:34:33,280
gravitational binding of that wall is overcome, the galaxies are

692
00:34:33,320 --> 00:34:36,079
pulled further and further apart than ing the filament, until

693
00:34:36,079 --> 00:34:37,239
eventually it snaps.

694
00:34:37,400 --> 00:34:40,239
Speaker 1: And when the filament separating two void bubbles finally breaks,

695
00:34:40,320 --> 00:34:41,440
what happens.

696
00:34:41,159 --> 00:34:45,599
Speaker 2: The voids merge. Two massive pockets of nothingness join forces

697
00:34:45,639 --> 00:34:50,119
to become an even larger supervoid. It is hydrodynamically similar

698
00:34:50,119 --> 00:34:52,440
to watching soap bubbles pop and merge in a sink,

699
00:34:52,880 --> 00:34:55,360
but on a scale of hundreds of millions of light years.

700
00:34:55,840 --> 00:34:58,639
The voids are systematically consuming the cosmic web.

701
00:34:58,960 --> 00:35:02,159
Speaker 1: That completely lips the script on how we view astronomy.

702
00:35:03,079 --> 00:35:06,159
For centuries, human beings have looked up and studied the light.

703
00:35:06,719 --> 00:35:09,719
We have charted the stars, mapped the galaxies, and track

704
00:35:09,760 --> 00:35:10,400
the clusters.

705
00:35:10,440 --> 00:35:12,480
Speaker 2: We followed the bright spots exactly.

706
00:35:12,639 --> 00:35:15,360
Speaker 1: We spend all our time analyzing the stuff because we

707
00:35:15,440 --> 00:35:18,039
naturally assume the stuff was the story. But when you

708
00:35:18,079 --> 00:35:21,360
look at the cosmological models of the far future, the

709
00:35:21,400 --> 00:35:24,079
stars and galaxies are just the leftover debris.

710
00:35:24,159 --> 00:35:26,719
Speaker 2: They are the crumbling scaffolding of a dying structure.

711
00:35:27,199 --> 00:35:29,599
Speaker 1: If we truly want to understand the mechanics and the

712
00:35:29,679 --> 00:35:33,119
ultimate fate of our universe. We cannot just study the light.

713
00:35:33,800 --> 00:35:36,320
The most important physics in the universe are happening in

714
00:35:36,320 --> 00:35:36,760
the dark.

715
00:35:36,920 --> 00:35:40,559
Speaker 2: Because the darkness is the dominant mechanism. The projections based

716
00:35:40,599 --> 00:35:43,800
on our current understanding of dark energy and void kinematics

717
00:35:43,800 --> 00:35:46,239
are stark. This is the path toward the Big.

718
00:35:46,119 --> 00:35:48,559
Speaker 1: Freeze or the Big rip, the end of everything.

719
00:35:48,880 --> 00:35:52,960
Speaker 2: Yes, in the far future, these supervoids will continue to

720
00:35:53,000 --> 00:35:58,119
expand relentlessly. They will crush and isolate the remaining galaxy clusters,

721
00:35:58,360 --> 00:36:00,920
pushing them so far apart that light will never reach

722
00:36:00,960 --> 00:36:05,000
one another. The acceleration will continue until the voids consume.

723
00:36:04,679 --> 00:36:06,840
Speaker 1: Everything, just one big empty room.

724
00:36:06,960 --> 00:36:10,480
Speaker 2: Eventually, the entire observable universe will be nothing more than

725
00:36:10,519 --> 00:36:15,159
a single, infinitely expanding void. The loneliest place in existence

726
00:36:15,239 --> 00:36:18,360
won't just be a specific region of space you can visit.

727
00:36:18,599 --> 00:36:19,920
It will be all of space.

728
00:36:20,519 --> 00:36:23,920
Speaker 1: The nothingness is going to eat everything until there's only

729
00:36:23,960 --> 00:36:27,400
nothing left. That is an incredibly heavy physical realization to

730
00:36:27,400 --> 00:36:28,039
carry around.

731
00:36:28,159 --> 00:36:29,000
Speaker 2: It is profound.

732
00:36:29,039 --> 00:36:30,880
Speaker 1: It really does bring us back down to Earth with

733
00:36:30,920 --> 00:36:34,400
a completely altered perspective. We started this discussion by talking

734
00:36:34,400 --> 00:36:36,400
about the experience of looking up at a night sky

735
00:36:36,519 --> 00:36:37,239
full of stars.

736
00:36:37,280 --> 00:36:38,519
Speaker 2: The times square analogy.

737
00:36:38,679 --> 00:36:41,559
Speaker 1: Right. But now when you go outside tonight and look

738
00:36:41,599 --> 00:36:43,679
up at that Kansas, the light doesn't seem quite so

739
00:36:43,719 --> 00:36:47,679
dominant anymore. Now you know that just beyond those stars

740
00:36:47,760 --> 00:36:52,679
wrapping around our entire cosmic neighborhood are these invisible, massive,

741
00:36:53,119 --> 00:36:54,679
actively inflating voids.

742
00:36:54,719 --> 00:36:56,000
Speaker 2: They are always there.

743
00:36:55,960 --> 00:36:59,039
Speaker 1: They are surrounding us. They are stretching the fabric of reality,

744
00:36:59,519 --> 00:37:03,519
and they are quietly, methodically dictating the final destiny of

745
00:37:03,559 --> 00:37:07,239
everything we know. The emptiness isn't just the backdrop of

746
00:37:07,280 --> 00:37:10,239
the cosmos. The emptiness is the main character.

747
00:37:10,440 --> 00:37:14,239
Speaker 2: It forces a profound paradigm shift. It is physically humbling,

748
00:37:14,320 --> 00:37:18,159
but you know, it also highlights the incredible statistical privilege

749
00:37:18,559 --> 00:37:22,440
of existing in this specific bustling era of the universe's

750
00:37:22,480 --> 00:37:25,159
life span, the stiliferous era, the.

751
00:37:25,079 --> 00:37:25,800
Speaker 1: Era of lights.

752
00:37:25,960 --> 00:37:29,840
Speaker 2: Exactly we happen to exist on the specific dense thread

753
00:37:29,880 --> 00:37:31,920
of the cosmic web at a time when we can

754
00:37:32,000 --> 00:37:35,119
still see the stars before the expanding voids isolate them forever.

755
00:37:35,199 --> 00:37:37,480
Speaker 1: It really makes you appreciate the light while we still

756
00:37:37,480 --> 00:37:39,840
have the physics to support it. And before we go,

757
00:37:39,880 --> 00:37:42,440
I want to leave you with one final thought to ponder.

758
00:37:42,440 --> 00:37:45,519
A thought experiment based on those lonely little void galaxies

759
00:37:45,519 --> 00:37:48,000
we talked about earlier, it should be cut. Imagine if

760
00:37:48,000 --> 00:37:52,760
you will, that the specific stellar nucleosynthesis in biological evolution

761
00:37:52,960 --> 00:37:56,719
that created humanity hadn't happened here in the chaotic, crowded

762
00:37:56,800 --> 00:38:00,519
Milky Way. Imagine if Earth had formed around a risteam

763
00:38:00,599 --> 00:38:04,920
blue star deep inside one of those rare isolated void

764
00:38:04,960 --> 00:38:07,760
galaxies in the center of the Bood's supervoid, the.

765
00:38:07,800 --> 00:38:09,119
Speaker 2: Completely different vantage point.

766
00:38:09,199 --> 00:38:11,440
Speaker 1: If early humans had looked up at the night sky

767
00:38:11,639 --> 00:38:15,159
and seen absolutely nothing, no weather star, is, no bright

768
00:38:15,239 --> 00:38:18,119
band of the Milky Way galaxy spanning the horizon, just

769
00:38:18,159 --> 00:38:23,079
an endless, suffocating black void in every single direction. How

770
00:38:23,119 --> 00:38:24,639
do you think human history would have changed?

771
00:38:24,800 --> 00:38:26,119
Speaker 2: That's a fascinating question.

772
00:38:26,440 --> 00:38:30,440
Speaker 1: How would our philosophy, our early religions, and the foundations

773
00:38:30,440 --> 00:38:33,920
of our sciences have developed differently if our immediate environment

774
00:38:34,000 --> 00:38:37,719
looked like the ultimate sensory deprivation chamber. Would a civilization

775
00:38:37,800 --> 00:38:41,159
surrounded by total darkness ever develop the desire to invent

776
00:38:41,199 --> 00:38:44,440
telescopes in explore space, or would the psychological weight of

777
00:38:44,480 --> 00:38:46,519
the dark keep us entirely focused inward?

778
00:38:46,639 --> 00:38:49,239
Speaker 2: It's hard to even imagine the psychological impact.

779
00:38:48,840 --> 00:38:51,360
Speaker 1: Of that it really is, what do you think? Drop

780
00:38:51,400 --> 00:38:53,679
your theories in the comments. We would absolutely love to

781
00:38:53,719 --> 00:38:56,719
read your take on this cosmic what if. Thank you

782
00:38:56,760 --> 00:38:58,679
so much for joining us on this deep dive into

783
00:38:58,719 --> 00:39:02,159
the source material on thrilling Threads. Thanks for listening, Keep

784
00:39:02,199 --> 00:39:06,440
looking up, but more importantly, stay intensely curious about the

785
00:39:06,519 --> 00:39:10,320
massive dark spaces between those stars. Until next time,