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Scientists Just Found an Even Bigger Cosmic Void · Boring Science

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Speaker 1: There's a region of space so empty that if our
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galaxy existed there, humanity wouldn't have discovered other galaxies until
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the nineteen sixties. We're talking about voids so vast they
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make the distance between galaxies look like neighboring houses. And
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here's what keeps astronomers awake at night. These voids are growing,
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actively tearing apart the cosmic web that holds our universe together.
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Right now, as you're watching this, invisible forces are stretching
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space itself, not just moving galaxies apart, but creating expanding
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bubbles of nothingness that dwarf anything you can imagine. We're
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going to explore what these cosmic voids actually are, why
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they're spreading, and what it means for the ultimate fate
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of everything that exists. When you look up at the
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night sky, you see star lots of them. This creates
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an illusion that space is densely packed with matter, But
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zoom out far enough and you'd discover something unsettling. The
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universe isn't evenly distributed at all. Instead, it resembles Swiss
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cheese or maybe soap foam. Galaxies cluster along thin filaments
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and walls surrounding enormous regions of almost nothing. These aren't
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just gaps between galaxies. Their structures so large they challenge
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our ability to comprehend scale. The typical cosmic void stretches
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thirty to three hundred million light years across. To put
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that in perspective, our entire Milky Way galaxy is only
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about one hundred thousand light years in diameter. You could
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line up three thousand milky Ways across a single void
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and still have room left over. But calling them empty
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isn't quite accurate. Even the most desolate void contains about
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fifteen percent of the average matter density of the universe.
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That might sound like a lot until you realize it
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means these regions are eighty five percent emptier than empty
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space should be. Voids have a mean density less than
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a tenth of the cosmic average. They're not vacuum in
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the absolute sense, but they're as close as nature gets
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on these scales. The discovery of these structures fundamentally changed cosmology.
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In nineteen eighty one, astronomer Robert Kirshner was conducting a
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survey of galactic redshifts, trying to map the large scale
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structure of the universe. What he found in the constellation
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Berta's stopped him cold, a spherical region of space roughly
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two hundred million light years in radius containing just sixty galaxies.
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Based on the density of galaxies in surrounding regions, there
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should have been about two thousand. This became known as
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the Buta's Void, colloquially called the Great Nothing. Its center
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sits seven hundred million light years from Earth. And here's
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the part that makes you question your place in the cosmos.
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If the Milky Way had formed at the center of
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this void instead of where it actually is, our entire
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understanding of the universe would have been delayed by decades.
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We wouldn't have had the telescopes powerful enough to detect
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other galaxies until the nineteen sixties. Think about what that means.
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All of human history, all our myths about the cosmos,
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all our early astronomy, would have a curd while staring
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out at essentially nothing beyond our own galaxy. The universe
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would have appeared far smaller, far lonelier, far more mysterious
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than it actually is. We got lucky with our cosmic address.
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But the Boater's Void isn't alone. It isn't even the
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largest void we've discovered that distinction belongs to the Eridanus Supervoid,
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a massive cigar shaped region one point eight billion light
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years wide. Its center is located about two billion light
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years from Earth, making it the dominant under density of
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matter in our galactic neighbourhood. This thing contains about thirty
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percent less matter than the surrounding regions. What makes the
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Erdanus Supervoid particularly interesting is its connection to something called
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the CMB cold spot. When astronomers mapped the cosmic microwave
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background radiation that faint after glow from the Big Bang
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that fills all of space, they found an anomaly, a
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region of the sky that appears unusually cold compared to
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the average temperature. This cold spot is about seventy microkelvins
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colder than the average CMB temperature. At some points, it
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drops to one hundred forty microkelvins below average. For years,
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scientists debated what could cause this. Then they discovered the
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Eridana Supervoid, sitting in the same direction. The connection isn't coincidental.
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When radiation from the early universe passes through a supervoid,
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it loses energy. The void's gravitational pull is weaker than
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average space, so photons climbing out of it experience less resistance.
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This creates a temperature deficit in the cosmic microwave background.
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The supervoid essentially leaves a shadow in the universe's baby picture.
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Now here's where it gets personal. You might be living
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in one. The KBC void, named after astronomers Ryan Keenan,
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Amy Barger, and Lennox Cowie, is an immense region roughly
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one to two billion light years in diameter, and according
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to current observations, the Milky Way sits near its center.
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This creates a massive problem for cosmology. The standard model
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assumes matter is more or less evenly distributed throughout the universe.
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You can't just have a billion light year under density
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with our galaxy conveniently placed in the middle. Yet that's
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exactly what the evidence suggests. Some researchers think this might
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explain one of the biggest mysteries in modern cosmology, the
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Hubble tension. The Hubble constant measures how fast the universe
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is expanding. When scientists calculate it using observations of the
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cosmic microwave background and Barrion acoustic oscillations, they get one
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number about sixty seven to sixty eight kilometers per second
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per megaparsec. When they measure it using galactic supernovae and
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Cepheide variables, they get a different number, about seventy two
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to seventy five. These methods shouldn't disagree, but they do.
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What if we're inside a void? Galaxies within a void
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experience gravitational pull from the denser regions outside. This creates
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a local outward flow that makes the universe appear to
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expand faster than it actually does on average. You can
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think of a supervoid as having concentrated negative mass. It
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exerts a repulsive gravitational effect, raising the redshifts of galaxies
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beyond what cosmic expansion alone would cause. The theory method
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averages the Hubble constant over the entire universe. The observational
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method only calculates it within the KBC supervoid, where we
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happen to live. If the KBC void is real, it
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would make our local measurements higher than the universal average.
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This could solve the Hubble tension. It would also mean
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our view of cosmic expansion has been skewed by our
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location this whole time. But voids aren't just passive features
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of the cosmic landscape. They're not empty bubbles sitting still
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in space. They're growing, actively expanding, and they're doing it
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faster than the regions around them. This happens becase because
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of how gravity works at cosmic scales. In dense regions,
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where galaxies cluster together, gravity wins it pulls matter closer,
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fighting against the expansion of space. But in voids, where
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density is already low, cosmic expansion dominates. There's not enough
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matter to generate sufficient gravitational attraction. Space stretches faster than
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matter can accumulate over time. This leads to increasingly large
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and empty regions. The voids grow by draining matter from
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their interiors. Any galaxy unlucky enough to form inside a
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void gets pulled toward the denser walls surrounding it. This
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creates a feedback loop. Less matter means weaker gravity, which
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means faster expansion, which pushes the remaining matter outward even
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more effectively, the void evacuates itself. Imagine you're standing in
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a crowd of people. Everyone is slowly shuffling away from
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you in all directions. At first, there are still people nearby,
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but as they move farther out, the space around you grows.
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Eventually you're standing in a clearing, then that clearing expands
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into a field, then a desert. The people at the
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edges keep moving away, and new empty space keeps appearing
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where they used to be. That's essentially what's happening inside
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cosmic voids, except instead of people, its galaxies, and instead
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of a field, it's hundreds of millions of light years
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of increasingly empty space. This process is driven by something
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we still don't fully understand, dark energy. About sixty eight
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percent of the universe is made of this mysterious stuff.
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We can't see it, we can't detect it directly, but
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we know it exists because of what it does. It
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makes the universe expand at an accelerating rate. Einstein predicted
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this sort of He proposed that empty space itself could
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possess energy. Because this energy is a property of space,
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it wouldn't dilute as space expands. Instead, as more space
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comes into existence, more dark energy appears with it. This
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creates a runaway effect. Expansion generates more space, which generates
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more dark energy, which drives more expansion. For a long time,
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cosmologists assumed dark energy was constant, a fixed property of
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the vacuum, but recent data from the Dark Energy Spectroscopy
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instrument suggests something more complex. Dark energy might be changing
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over time. The measurements indicate it was stronger in the
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distant past than it is now. The parameter scientists used
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to describe dark energy, called W, appears to have been
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lower than negative one point four billions of years ago.
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Today it's closer to negative zero point eight. This is bizarre.
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It suggests dark energy isn't just a cosmological constant, but
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a dynamic field that evolves. If that's true, it has
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profound implications for the ultimate fate of the universe, and
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it changes how we think about voids, because voids are
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where dark energy does its most important work. In dense
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regions like galaxies or galaxy clusters, gravity dominates. Dark energy
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is present, but its effects are overwhelmed by the gravitational
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attraction of all that concentrated matter. The accelerated expansion of
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the universe doesn't occur inside these dense structures. It occurs
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in the voids. The vast empty regions between galaxy filaments
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are where dark energy's influence becomes dominant. Without significant matter
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to counteract it, dark energy stretches space unimpeded. The voids
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expand faster than the cosmic average. They press against the
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surrounding cosmic web like inflating balloons. Over time, they push
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the filaments and walls farther apart. This means voids aren't
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just empty, they're active agents in cosmic evolution. They're the
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regions where the universe's expansion is actually happening. The intricate
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network of galaxies, clusters, and filaments that astronomers observe today
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is temporary. As dark energy pushes space outward, the voids grow,
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they stretch the cosmic web. Eventually they'll tear it apart completely.
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The timescale for this is enormous. We're talking billions of years,
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but the process is already underway. In about one hundred
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billion years, distant galaxies will be pulled away from us
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so fast that their light will never reach us again.
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The cosmic horizon will shrink. Future astronomers, if they exist,
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will look out at a much lonelier universe than we
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see today. Beyond that, the fate depends on what dark
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energy actually is. If it remains constant, the universe will
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experience heat death, stars will burn out, matter will decay,
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black holes will evaporate through hawking radiation. Eventually nothing remains
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but a dilute gas of photons and leptons spreading farther
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and farther apart in an ever expanding void. The universe
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won't end with a bang. It'll end with eternal silence.
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But if dark energy strengthens over time, we face something
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far more violent, the big Rip. In this scenario, the
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acceleration becomes so extreme that it overcomes not just gravity
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but all the fundamental forces. Galaxies tear apart, then solar systems,
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then planets, then atoms themselves. The universe rips itself to
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shreds at the level of elementary particles. Current observations favor
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heat death over the big Rip, but the recent DESI
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findings suggests dark energy might be more complex than we thought.
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We don't know enough yet to rule anything out definitively.
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What we do know is this, the voids are expanding.
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They're pressing against the cosmic web, and over immense spans
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of time, they're pulling the universe's large scale structure apart.
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The beautiful foam like pattern of filaments and walls surrounding
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vast empty regions won't last forever. It's already dissolving slowly
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but inexorably into isolated island universes, drifting alone in an
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expanding sea of nothing. This story has landmarks vast cosmic
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structures so empty they defy comprehension, places where the universe
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reveals what it's becoming. In nineteen eighty one, astronomer Robert
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Kirshner was conducting a routine survey. He was mapping galaxies
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by measuring their redshift, trying to understand the large scale
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structure of the universe. Standard work, nothing unusual expected. Then
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he found something that shouldn't exist. A region of space
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roughly spherical in shape, centered about seven hundred million light
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years from Earth. He expected to find around two thousand
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galaxies in a volume that size. He found sixty the
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Boater's Void. Astronomers started calling it the Great Nothing. Its
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radius stretches sixty two megaparsex. That's nearly two hundred million
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light years across, one of the largest known voids in
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the observable universe. To put that scale into perspective, astronomer
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Greg Aldering calculated something unsettling. If the Milky Way had
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been located at the center of the Boater's Void, we
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wouldn't have discovered other galaxies existed until the nineteen sixties.
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The nearest galaxies would have been so far away that
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even our most powerful telescopes of earlier eras couldn't have
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detected them. Think about that for a moment. Our entire
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understanding of cosmology, of the universe's structure and evolution depends
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on being able to observe other galaxies. The Hubble expansion,
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dark matter, dark energy, all discovered by studying galaxies beyond
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our own. If we'd evolved in the Boat's Void, humanity
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would have spent millennia believing the Milky Way was the
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entire universe, a lonely island of stars in an infinite
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black ocean. We got lucky with our cosmic address. But
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the Boater's Void isn't unique. It's just one example of
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a phenomenon that appears throughout the universe. Astronomers have catalogued
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hundreds of voids, some smaller, some larger. The Eridanus supervoid
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spans one point eight billion light years. It's associated with
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the cold spot in the cosmic Microwave background, a mysterious
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region of space that appears colder than it should be,
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possibly because photons lose energy climbing out of such a
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massive under density. These structures challenge our understanding of cosmic evolution.
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According to the standard cosmological model, matter should be distributed
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relatively evenly throughout the universe on the largest scales. Small fluctuations, yes,
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but nothing that should create such enormous empty regions. Yet
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here they are vast bubbles of near nothingness, containing les
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less than one tenth the average density of matter in
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the universe. How did they form? The answer takes us
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back to the Big Bang itself. In the first moments
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after the universe began, quantum fluctuations created tiny variations in density.
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Some regions had slightly more matter, others slightly less. These
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differences were incredibly small, variations of just one part in
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one hundred thousand, but gravity amplifies imbalances. Regions with more
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matter attracted even more matter. They grew denser. Regions with
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less matter lost what little they had to their denser neighbours.
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They became emptier. Over billions of years, this process created
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the cosmic web. Dense regions collapsed into galaxy clusters connected
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by filaments. Low density regions expanded into voids. It's a
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natural consequence of how gravity sculpts space when you start
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with uneven initial conditions. But there's something else happening now,
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something that changes the story dark energy. In dense regions,
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galaxy clusters, galactic filaments, gravity still dominates. Matter is packed
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closely enough that its gravitational attraction overcomes the expansion of space.
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Galaxies in these regions stay gravitationally bound. The expansion doesn't
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tear them apart. In voids, there's not enough matter for
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gravity to resist. Dark energy dominates completely. Space expands unimpeded,
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stretching the voids larger and larger. They grow faster than
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the cosmic average. They press outward against the surrounding cosmic web,
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like inflating below boons. This means voids aren't passive features,
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their active participants in cosmic evolution, their engines of expansion
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gradually pulling the universe's structure apart, and we might be
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living inside one. The KBC void, named after astronomers Ryan Keenan,
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Amy Barger, and Lennox Cowie, is an immense under density
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roughly one to two billion light years across. Observations suggest
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the Milky Way sits near its center, we're in a
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region of significantly lower galaxy density than the cosmic average.
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This is a problem for cosmology. One of the biggest
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unsolved puzzles in modern physics is called the Hubble tension.
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When astronomers measure the universe's expansion rate using nearby supernovae
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and Cepheid variables, they get one answer about seventy three
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kilometers per second per megaparsec. When they measure it using
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the cosmic microwave background and large scale structure data, they
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get a different answer, about sixty seven kilometers per second
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per megaparsec. That's a significant discrepancy, too large to be
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experimental error. Something fundamental is wrong with our understanding. Some
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researchers think the KBC void might explain it. If we're
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inside a supervoid, we experience a gravitational pull from the
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denser regions outside. This creates a peculiar velocity motion that's
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separate from the Hubble expansion. Physicist Indronilbanic describes it like this.
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You can think of a supervoid as a homogeneous universe
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plus some concentrated negative mass. It has a repulsive gravitational effect.
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It raises the redshifts of galaxies beyond what cosmic expansion
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alone would produce. The theory method for measuring the Hubble
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constant averages expansion over the entire universe. The observational method
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only calculates it within the KBC supervoid. If we're in
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a region where expansion appears faster than average, that explains
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why local measurements don't match global ones. The universe isn't
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expanding faster everywhere, it's just expanding faster here. This solution
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remains controversial. Not all cosmologists accept it, but it highlights
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something important. Voids aren't just empty their regions where the
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geometry of space time itself differs from the cosmic average.
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They warp our measurements. They influence how we perceive the universe,
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and their gaines Larger computer simulations of cosmic evolution paint
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a clear picture. As dark energy continues pushing space outward,
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voids expand, they stretch the filaments connecting galaxy clusters. Over time,
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those filaments thin and eventually break the cosmic web fragments
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into isolated pieces. The timescale is immense, We're talking tens
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of billions of years, but the process is inevitable. If
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dark energy remains constant or strengthens, in about one hundred
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billion years, distant galaxies will recede so fast that their
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light can never reach us. The cosmic horizon shrinks. Future
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observers will see a much smaller, lonelier universe. Eventually, only
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the galaxies in our local gravitationally bound group remain visible.
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Everything else disappears beyond the ear expanding voids. But even
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that's temporary. Stars burn through their fuel and die. New
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stars can't form without fresh gas and dust. Galaxies go dark.
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Matter slowly decays, black holes evaporate through Hawking radiation. The
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universe trends toward maximum entropy, a state where everything is
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evenly spread and nothing interesting can happen anymore. Heat death,
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the Big Freeze, an eternal cosmic winter unless dark energy strengthens.
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The recent DEESI findings suggest dark energy might be dynamic,
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evolving over time. If it's getting stronger, the expansion accelerates faster.
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Eventually it overcomes not just gravity but all the fundamental
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forces holding matter together. Galaxies tear apart first, then solasite systems,
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then planets, then molecules, then atoms themselves. The universe rips
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itself to shreds at the level of elementary particles. This scenario,
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the Big Rip, is more violent than heat death. It's
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not a slow fade into darkness. It's a catastrophic unraveling
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of space time itself. Current data favors heat death. The
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Big rip requires phantom energy, a hypothetical form of dark
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energy with properties most physicists consider implausible, but we don't
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know enough about dark energy to rule it out completely.
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What we do know is that voids are central to
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both scenarios. There where dark energy does its work. They're
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the regions expanding fastest. They're already tearing the cosmic web apart,
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just very slowly. The beautiful foam like structure of filaments
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and walls surrounding vast empty regions won't last. It's dissolving.
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The voids are winning. But here's what makes this truly unsettling.
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Voids aren't completely empty. They contain their own internal structure,
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smaller voids within larger voids, tiny filaments connecting the few
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galaxies that do exist inside, even walls and clusters on
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smaller scales. It's a fractal pattern, self similar across different
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size scales. Computer simulations reveal this hierarchical architecture. When you
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zoom in on a void, you find miniature versions of
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the cosmic web structure. When you zoom in on those features,
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you find even smaller substructures. The pattern repeats all the
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way down. This complexity makes voids fascinating laboratories for studying
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galaxy evolution. The sixty galaxies in the Boter's void didn't
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form in typical environments. They evolved in near total isolation,
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no mergers, no close gravitational interactions, no dense surroundings stripping
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away their gas, their cosmic hermits. Studying them tells us
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what happens when galaxies develop alone. They tend to be smaller, bluer,
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and more gas rich than galaxies in dense environments. They
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form stars more slowly, they retain their spiral structures longer
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because nothing disturbs them. In some ways, void galaxies represent
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a purer form of galaxy evolution. They show what happens
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when you remove all the complicating factors of crowded environments.
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Their test cases for theory theoretical models, but there are
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also reminders of how hostile voids are to structure formation
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out of the enormous volume of the Boater's void, only
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sixty galaxies formed. The rest is just empty space, a
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testament to how thoroughly dark energy dominates these regions, and
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those voids are expanding into everything else. The cosmic web
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we observe today is a snapshot in time, a temporary configuration.
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Billions of years ago, the universe was denser, more uniform,
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The voids were smaller, the filaments thicker, galaxies closer together.
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Billions of years from now, the opposite will be true.
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Voids will dominate even more. Filaments will have thinned to
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nearly nothing. Galaxies will drift alone in expanding bubbles of emptiness.
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The universe is becoming less structured over time, more homogeneous,
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more void dominated. It's a slow motion dissolution of cosmic architecture.
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The voids are erasing the intricate patterns that gravity spent
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billions of years constructing. They're returning the universe to something
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closer to its initial state, uniform, featureless, empty, Except this time,
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there's no big bang to restart the process, no quantum
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fluctuations to seed new structure. Just endless expansion, endless emptiness,
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endless silence. This is what voids represent not just empty
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regions between galaxies, but the future of the universe itself.
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They're showing us where everything is headed, their previews of
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cosmic heat death, scattered throughout space and time. When you
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look at images of the cosmic web, those beautiful maps
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showing filaments of galaxies surrounding vast dark regions, you're seeing
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a battle between gravity and dark energy. Gravity trying to
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pull matter together, dark energy trying to push space apart.
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For now, gravity holds its own in the densest regions,
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but it's losing ground. The voids are expanding. They're pressing
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against the filaments from all sides, and eventually they'll win completely.
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The question isn't whether the voids will swallow the cosmic web.
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The question is how long it takes and what form
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the final expansion takes. Because the voids aren't just expanding
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into the structure around them, they're fundamentally changing what it
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means for structure to exist at all. The mechanics of
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how voids reshape space itself reveals something unsettling about the
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nature of expansion. When dark energy pushes space outward, it
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doesn't do so uniformly everywhere dense regions, galaxy clusters, filaments,
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massive walls of matter resist expansion through gravitational binding. Their
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internal gravity is strong enough to counteract dark energy's push.
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These structures stay coherent even as space expands around them,
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but voids have no such resistance. With less than a
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tenth of the universe's average density, voids offer almost nothing
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for gravity to work with. Dark energy encounters minimal opposition.
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Space expands faster in voids than anywhere else, much faster.
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This differential expansion creates a feedback loop. As voids expand,
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they become even less dense. Lower density means weaker gravity.
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Weaker gravity means less resistance to expansion. Less resistance means
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faster expansion. Faster expansion means lower density. The cycle accelerates itself. Meanwhile,
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the surrounding cosmic web experiences mounting pressure from all directions.
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Imagine being squeezed between expanding bubbles. That's the situation for
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every filament, every wall, every cluster. At the edges of voids,
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they're being compressed from multiple angles as voids press inward
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from all sides. Eventually, something has to give. The thinnest
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parts of filaments snap first. Galaxies at the edges drift
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away into expanding voids, the cosmic web develops, gaps holes
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appear in what were once continuous structures. Over billions of years,
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the web fragments into increasingly isolated piece. This process is
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already underway. We're witnessing it in real time through careful
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observations of galaxy distributions. Filaments are thinning, walls are stretching,
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the gaps between structures are widening measurably, and we're part
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of this process, whether we realize it or not. The
35:23
KBC Void, the massive under density surrounding our local cosmic neighborhood,
35:30
puts US in a peculiar situation. We're not in the
35:34
deepest part of this void. We're near the edge, in
35:38
a relatively dense region called the local sheet, but the
35:43
void extends for roughly a billion light years around us.
35:48
This location affects everything we measure about cosmic expansion. When
35:53
astronomers observe distant galaxies to calculate the Hubble constant, the
35:59
rate at which the US universe expands, their measuring expansion
36:03
through the KBC Void, but that's not representative of the
36:08
universe as a whole. Expansion is faster inside voids than
36:14
outside them. This creates what's called the Hubble tension. Two
36:18
methods of measuring cosmic expansion yield different answers. Observations of
36:24
nearby galaxies and supernovae give values around seventy two to
36:30
seventy five kilometers per second per megaparsec. Measurements from the
36:35
cosmic microwave background light from the early universe give values
36:40
around sixty seven to sixty eight. That's a significant discrepancy,
36:46
not a rounding error, a genuine conflict that suggests either
36:51
our measurements are wrong or our understanding of cosmic expansion
36:56
is incomplete. Living inside a supervoid might explain this tension.
37:02
Galaxies inside a void experience gravitational pull from the denser
37:06
regions outside. This creates an effective outward force, a repulsive
37:13
effect that makes local expansion appear faster than the cosmic average.
37:18
From inside the void, the universe looks like it's expanding
37:23
more rapidly than it actually is. Think of it as
37:27
a perspective distortion. You're measuring expansion from inside a region
37:32
where expansion is locally enhanced. Your measurements are accurate for
37:38
your location, but don't reflect the global picture. Some cosmologists
37:44
argue the KBC Void can resolve the Hubble tension. Others
37:48
remain skeptical. The debate continues, but the possibility that we're
37:54
inside one of the universe's largest voids has profound implications
38:00
beyond just measurement issues. It means our view of the
38:03
cosmos is fundamentally shaped by emptiness. For most of human history,
38:09
we assumed Earth occupied a special place. Then we learned
38:14
we orbit an ordinary star in an ordinary galaxy, in
38:18
an ordinary part of the universe. The Copernican principle, the
38:24
idea that we're not special, became a cornerstone of cosmology.
38:29
But if we're inside a supervoid, that principle gets complicated.
38:34
Voids aren't typical. They represent extreme under densities. Less than
38:40
ten percent of the universe's volume consists of regions as
38:44
empty as the KBC void. Being inside one isn't necessarily
38:49
special in a meaningful sense, but its statistically unlikely, and
38:55
it affects what we can observe and how we interpret
38:58
those observations. Civilizations in different cosmic environments would develop different
39:06
cosmologies based on what they could see. A civilization in
39:11
the Boat's void would have faced extraordinary challenges discovering the
39:16
broader universe. With only sixty galaxies in a region spanning
39:22
two hundred million light years, their night sky would contain
39:27
almost nothing beyond their own galaxy, no nearby galactic neighbours,
39:33
no obvious evidence of a larger cosmic structure. Astronomer Greg
39:39
Aldering calculated that if the Milky Way had formed in
39:42
the center of the Boater's Void, we wouldn't have discovered
39:46
other galaxies until the nineteen sixties. Before that, our most
39:51
powerful telescopes wouldn't have been strong enough to detect the faint,
39:56
distant galaxies at the void's edge. Higher understanding of cosmology
40:02
would have been delayed by decades or centuries. We might
40:06
have developed completely different theories about the universe's structure. We
40:11
might have assumed our galaxy was alone, that the universe
40:15
consisted of a single island of stars surrounded by infinite emptiness.
40:22
Only with mid twentieth century technology would we have finally
40:26
detected those distant pinpoints of light and realize the truth.
40:33
This thought experiment highlights how profoundly our cosmic environment shapes
40:38
our understanding. We're fortunate to live in a relatively dense
40:44
region where galaxies are visible in abundance. Our view of
40:49
the cosmic web is clearer than it would be from
40:52
inside a void. But there's another more disturbing implication. As
40:57
voids continue expanding, future civilizations will face the same problem,
41:03
not because they're invoids like Burhas, but because expansion will
41:08
have pushed everything so far apart that the universe effectively
41:13
becomes a void from every perspective. Give it one hundred
41:18
billion years, maybe two hundred billion. Distant galaxy clusters will
41:24
have receded beyond the cosmic horizon, the boundary beyond which
41:29
expansion carries objects away faster than light can travel. They'll
41:34
disappear from view completely, not because they've been destroyed, but
41:40
because space between us and them is expanding too rapidly
41:45
for their light to ever reach us. Our descendants, if
41:49
any exist, will look up at a much emptier sky.
41:53
They'll see the local group, the Milky Way, Andromeda, and
41:58
the few dozen dwarf galaxies gravitationally bound to them. Everything
42:03
else will have vanished. No distant galaxies, no cosmic web,
42:08
no evidence of the larger universe. And here's the truly
42:13
unsettling part. They won't be able to discover cosmology the
42:18
way we did. The evidence we use to piece together
42:22
the Big Bang theory, the expansion of the universe, the
42:27
cosmic microwave background, the abundance of light elements. All of
42:33
that depends on observing distant objects. Without access to distant galaxies,
42:39
future astronomers will have no way to measure cosmic expansion.
42:45
They'll see a static universe containing only their local cluster.
42:49
The cosmic microwave background will still exist, but it will
42:53
have been redshifted to such long wavelengths that it becomes
42:57
essentially undetectable. The faint after glow of creation will fade
43:03
into invisibility. Future scientists will look out and see nothing
43:08
but their own galaxy cluster, surrounded by permanent darkness. They
43:13
might develop theories, they might speculate, but they won't have
43:18
the observational evidence we have today. The universe will have
43:22
hidden its own history through expansion. This raises an uncomfortable question,
43:29
what evidence are we missing right now? If the universe
43:33
has already expanded enough to push some structures beyond our
43:37
cosmic horizon, we might be in the same situation as
43:41
those future astronomers. We might be looking at an incomplete picture,
43:47
unaware of what we can't see. There could be structures, patterns,
43:52
or phenomena beyond our observational limits that would completely change
43:57
our understanding of cosmology. We wouldn't know, We couldn't know.
44:03
The information simply hasn't reached us yet and never will.
44:09
Voids guarantee that large portions of the universe remain forever unknowable.
44:15
Every void represents a region where structure formation failed, where
44:21
the initial density fluctuations were too small, where dark energy's
44:26
influence overwhelmed gravity before significant clustering could occur. These regions
44:33
tell us something important about the universe's initial conditions. The
44:39
size and distribution of voids constrain models of cosmic inflation,
44:44
the rapid expansion that occurred fractions of a second after
44:48
the Big Bang. Too many large voids would suggest different
44:52
inflationary parameters. Too few would point in another direction. By
44:58
mapping voids throughout the o observable universe, cosmologists can test
45:03
theories about the very earliest moments of cosmic history, but
45:08
voids also tell us about the future. The Eridanus supervoid
45:13
offers a particularly striking example. This cigar shaped void stretches
45:19
one point eight billion light years across, making it one
45:22
of the largest known structures. Its center sits two billion
45:27
light years away in the direction of the constellation Eridanus.
45:33
What makes this void especially interesting is its connection to
45:36
the CMB cold spot. The cosmic microwave background should be
45:41
nearly uniform. Tiny temperature fluctuations exist the seeds of cosmic structure,
45:49
but they're small. Most variations are around eighteen microkelvins. The
45:55
cold spot is different. At its most extreme, the cold
46:00
spot measures one hundred forty microkelvins colder than the average
46:05
CMB temperature. That's nearly eight times the typical variation. It's
46:11
an anomaly that shouldn't exist according to standard cosmological models,
46:16
unless it's caused by a supervoid. When CMB photons travel
46:21
through a void, they experience a subtle energy loss. The
46:26
void's expansion stretches space as photons cross it, slightly red
46:31
shifting their wavelengths. This redshift appears as a temperature decrease
46:36
when we measure the CMB. The Eridanus supervoid sits precisely
46:42
in the direction of the cold spot. Its size and
46:47
distance match what would be needed to create the observed
46:50
temperature anomaly. The correlation is strong enough that most cosmologists
46:56
now accept the connection. But here's what's to disturbing about this.
47:02
The Eridana supervoid is so massive that it noticeably affects
47:07
the cosmic microwave background. This isn't a small perturbation. This
47:13
is a structure so dominant in its region of space
47:17
that it leaves an imprint on the universe's oldest light.
47:22
The Void's gravitational influence, or rather its lack thereof, shaped
47:28
space time enough to create a detectable signal in radiation
47:32
that has been traveling for nearly fourteen billion years. That
47:36
reveals the true scale of void's influence. They're not passive features.
47:42
They're active participants in cosmic evolution. They shape the flow
47:47
of matter, the propagation of light, the curvature of spacetime itself,
47:52
and they're growing larger and more influential with every passing moment.
47:58
The question isn't where the voids will dominate the universe's structure.
48:03
They already do. They occupy more volume than all the filaments, walls,
48:09
and clusters combined. The question is what happens as they
48:14
continue expanding and merging small voids grow, large voids become supervoids.
48:21
Supervoids merge into even larger structures. The hierarchy continues upward
48:27
indefinitely as long as dark energy keeps driving expansion. Eventually,
48:33
you reach a point where the distinctions become meaningless. When
48:37
voids dominate so thoroughly that the cosmic web has fragmented
48:41
into isolated islands, the universe becomes effectively homogeneous again, not
48:48
because matter is evenly distributed, but because the distances between
48:53
structures are so vast that local variations don't matter on
48:57
cosmic scales. It's a strange invert The universe starts nearly hummogeneous.
49:03
After the Big Bang, structure formation breaks that homogeneity. Gravity
49:09
creates the cosmic web, but dark energy, working through voids
49:15
gradually erases those structures and returns the universe to large
49:19
scale uniformity. Except this time, the uniformity is one of
49:25
emptiness rather than density. The cosmic web we observe today
49:30
sits at a special moment in universal history, early enough
49:35
that structure still exists, late enough that we can observe it.
49:41
This window won't remain open forever. In a few billion years,
49:46
astronomers living in the Milky Way will look out at
49:50
the night sky and see something fundamentally different from what
49:54
we observe today. They'll still see stars. The milk Huway
50:00
itself will remain, likely merged with Andromeda. By then, our
50:06
local group of galaxies will persist as a gravitationally bound structure.
50:12
But beyond that darkness, the cosmic web will have faded
50:17
from view. The distant galaxies we photograph today, those beautiful
50:22
spiral and elliptical galaxies scattered across deep field images, will
50:28
have receded beyond the cosmic horizon. The expansion of space
50:33
will have carried them away faster than light can travel.
50:37
Not because they're moving through space faster than light, but
50:41
because space itself is expanding between us and them. This
50:47
isn't speculation. The mathematics is straightforward. We can calculate exactly
50:53
when different structures will disappear from our observable universe. The
50:58
most distant galaxies we currently observe are already on the edge.
51:03
Their light has been traveling for over thirteen billion years
51:07
to reach us, but they're not thirteen billion light years away.
51:12
Due to cosmic expansion. They're now more than thirty billion
51:17
light years distant. Every year, more galaxies cross the threshold
51:22
where their light will never reach us. Within about one
51:26
hundred billion years, every galaxy beyond our local gravitationally bound
51:31
cluster will have vanished from view. Future astronomers won't be
51:36
able to observe them. No matter how powerful their telescopes become,
51:42
the light simply won't arrive. Those galaxies will still exist, presumably,
51:49
but they'll be causially disconnected from us, separated by expanding voids.
51:55
That space itself has stretched beyond any possible contact. That's
52:01
when the real isolation begins. Imagine being an astronomer in
52:05
that far future. You'd have incredible technology, telescopes that dwarf
52:11
anything we possess, computational power we can't conceive. But when
52:16
you point your instruments at the sky beyond your local cluster,
52:21
you'd see nothing. No distant galaxies, no quasers, no cosmic
52:27
microwave background radiation to study. You'd have no way to
52:31
discover the Big Bang, no evidence for cosmic expansion, no
52:36
ability to measure the universe's age or composition. Your entire
52:41
understanding of cosmology would be limited to your local island
52:45
of matter floating in an ocean of expanding emptiness. Would
52:51
you even realize your universe was larger than what you
52:54
could observe? Probably not. You'd have no reason to suspect it.
53:00
Your observable universe would appear to be just your local cluster,
53:04
surrounded by infinite darkness. You'd likely conclude that the universe
53:09
is static, eternal, and small. All the cosmological knowledge we've
53:15
gained over the past century would be inaccessible to you,
53:20
not because you lack intelligence or curiosity, but because the
53:25
evidence has literally moved beyond reach. This raises an uncomfortable question.
53:32
What knowledge is already beyond our reach? We can only
53:37
observe the universe within our current cosmic horizon. Light from
53:42
beyond that boundary hasn't had time to reach us yet.
53:46
But as the universe expands, that horizon isn't growing to
53:50
encompass more space, it's shrinking. In terms of what will
53:54
ever be able to observe. There could be structures, phenomena
53:59
in entire categories of cosmic objects that exist beyond what
54:04
we can currently see, and if they're in regions that
54:07
are expanding away from us faster than light, will never
54:11
detect them. Ever, the voids are central to this process.
54:18
They're not passive bystanders. They're the mechanism through which cosmic
54:22
isolation occurs. As voids expand, they push everything apart. The
54:29
filaments stretching between them grow longer and thinner. Galaxy clusters
54:34
become more isolated. The cosmic web transitions from an interconnected
54:40
network to scattered islands. This process accelerates over time. Dark
54:46
energy density remains constant per unit volume, but as the
54:50
universe expands, the total volume of space increases. More volume
54:56
means more dark energy. More dark energy means faster expansion.
55:01
Faster expansion means voids grow larger. It's a runaway process
55:07
with no natural stopping point. Right now, we're living in
55:11
what might be the optimal epoch for observational cosmology, early
55:16
enough that the cosmic web still exists, late enough that
55:21
we've developed the technology to observe it. This window is temporary.
55:27
Our descendants, billions of years from now, will have access
55:31
to less cosmological information than we do, not more. The
55:37
universe won't have changed its fundamental nature, but the observable
55:42
portion will have shrunk dramatically. Unless we preserve that knowledge,
55:47
unless we record everything we discover about the distant universe,
55:52
about cosmic expansion, about the structures that exist beyond our
55:57
local cluster. Because of Eventually there will be no way
56:02
to verify these observations independently. Future civilizations will have to
56:07
take our word for it, or they'll dismiss it as mythology,
56:12
ancient stories about a time when the sky was filled
56:16
with countless galaxies, when light from the beginning of time
56:20
could be detected, when the universe was young and full
56:24
of structure. Without evidence, how would they distinguish scientific observation
56:30
from creative fiction. This is already happening on smaller scales.
56:36
There are galaxies that were visible to us a billion
56:39
years ago that have now receded beyond observation. We could
56:44
have photographed them then if we had possessed the technology,
56:49
but we didn't, and now they're gone from our view permanently.
56:54
What did we miss? What structures existed in the observable
56:59
universe one billion years ago, five billion years ago, ten
57:04
billion years ago that we can no longer see because
57:07
they've been carried beyond the cosmic horizon. We'll never know.
57:13
That information is lost, not destroyed, but inaccessible, which amounts
57:18
to the same thing from our perspective. The voids don't
57:23
just separate us spatially, they separate us temporarily. They cut
57:27
us off from information about the universe's past and future.
57:32
Consider the cosmic microwave background. Right now, we can detect
57:37
it clearly. It provides our most detailed information about the
57:42
early universe. But the CMB is redshifting. As the universe expands,
57:49
its wavelength is being stretched to longer and longer values.
57:54
Eventually it will redshift into radio wavelengths so long they
57:58
become impossible to detect against background noise. The CMB will
58:04
fade from observability. When that happens, future astronomers will lose
58:10
access to direct observations of the universe when it was
58:14
three hundred eighty thousand years old. They'll have to rely
58:19
on theoretical models and historical records. No independent verification will
58:25
be possible. The same applies to distant galaxies. We can
58:30
currently observe galaxies as they appeared billions of years ago.
58:35
Their light carries information about cosmic history, about how galaxies
58:40
formed and evolved, about the expansion rate at different epochs.
58:46
As those galaxies recede beyond the horizon, that information vanishes.
58:52
We lose our window into those periods of cosmic history.
58:56
The universe is becoming observationally simpler over time, more homogeneous,
59:02
less structured, not because structure is disappearing, but because we're
59:08
losing the ability to see it. In the far future,
59:12
the observable universe will appear almost perfectly uniform, a single
59:17
cluster of galaxies surrounded by darkness, no evidence of larger
59:22
scale structure, no visible cosmic evolution, just static isolation. That's
59:29
the long term consequence of expanding voids, not just physical separation,
59:35
but informational isolation. The universe fragments into causially disconnected regions,
59:43
each unable to communicate with or observe the others. We're
59:47
watching this process unfold in real time. Every year, roughly
59:52
twenty thousand galaxies cross beyond our cosmic event horizon. They're
59:58
still out there, presumably, but their light will never reach us.
1:00:03
They've become part of a universe we can no exists
1:00:07
but cannot observe. This isn't some distant future concern. It's
1:00:12
happening now. The universe we can observe is smaller today
1:00:17
than it was yesterday, and it will be smaller tomorrow
1:00:20
than it is today. The window is closing, not quickly
1:00:25
by human standards, but cosmically speaking, we're in the final
1:00:31
moments of a brief era when the universe is both
1:00:34
large enough to contain magnificent structure and young enough that
1:00:39
we can still observe it. What are we doing with
1:00:43
this opportunity. We're mapping the cosmic web in unprecedented detail.
1:00:48
Surveys like DEESI are cataloging millions of galaxies, measuring their
1:00:54
positions and velocities, reconstructing the large scale structure of the universe.
1:01:00
That data will remain valuable long after the structures themselves
1:01:05
have receded from view. We're studying the cosmic microwave background
1:01:10
with ever increasing precision, extracting every bit of information we
1:01:15
can about the early universe before that signal fades beyond detection.
1:01:21
We're observing distant galaxies and quasers, looking back in time
1:01:26
to witness cosmic history as it actually unfolded, building a
1:01:31
record that future generations will be unable to verify but
1:01:36
might still find useful. Because once the voids have expanded sufficiently,
1:01:42
once the cosmic web has fragmented into isolated islands, once
1:01:47
the observable universe has shrunk to just our local cluster.
1:01:51
There will be no second chances, no way to recover
1:01:55
that lost information. The universe won't care. It will continue
1:02:01
expanding regardless of whether anyone is observing it. Voids will
1:02:06
keep growing, dark energy will keep pushing, the cosmic web
1:02:11
will keep fragmenting. But for conscious beings trying to understand
1:02:16
the cosmos, this represents an irreversible loss, a closing door
1:02:22
that will never reopen. You might wonder whether this matters.
1:02:26
After all, we're talking about time scales of billions of years.
1:02:31
Humanity will likely be unrecognizable by then, if it exists
1:02:35
at all. But the principal matters. The universe is not
1:02:40
infinitely knowable. There are limits to what can be observed.
1:02:45
Not because of technological constraints, but because of the fundamental
1:02:50
structure of space time. Information is being lost constantly, not destroyed,
1:02:57
but moved beyond reach. The expanding voids ensure this. They're
1:03:03
not just empty regions of space. They're information barriers, causality boundaries,
1:03:09
horizon generators, and they're winning slowly, inexorably. They're separating everything
1:03:17
from everything else, breaking connections, severing information flows, fragmenting the
1:03:24
universe into isolated pockets. The cosmic web we observe today
1:03:29
is temporary, a fleeting pattern that emerged from the Big
1:03:33
Bang's quantum fluctuations, grew under gravity's influence, and is now
1:03:38
being dismantled by dark energy's relentless push. We're living in
1:03:43
the middle of that story, after the formation, before the dissolution,
1:03:49
in the brief window when structure exists and can be observed.
1:03:54
That makes our era special, not because the universe treats
1:03:59
us differently, but because we happen to exist at a
1:04:02
time when cosmological observation is possible on the largest scales.
1:04:09
Future civilizations won't have that privilege. They'll inherit a darker, emptier,
1:04:15
more isolated cosmos, one where the evidence for the universe's
1:04:20
grand structure has receded beyond the horizon, carried away by
1:04:25
the same expanding voids that shape that structure. In the
1:04:29
first place, the voids give and the voids take away.
1:04:34
They created the space for cosmic structure to form. Now
1:04:38
they're erasing it from view, one galaxy at a time.
1:04:43
But there's another angle to this cosmic isolation that we
1:04:46
haven't considered. Yet one that makes the situation considerably more unsettling.
1:04:53
The voids aren't just passively expanding, they're actively changing the
1:04:59
rules of physic in their regions of influence. This sounds
1:05:03
like science fiction, but its direct consequence of general relativity.
1:05:09
Space time isn't a static background where events happen. It's dynamic,
1:05:15
responsive to the presence or absence of mass and energy
1:05:20
where there's matter. Spacetime curves where there's emptiness. It behaves differently.
1:05:27
Inside a massive void, the local geometry of spacetime shifts
1:05:32
slightly subtly, but measurably. Galaxies inside voids experience gravitational effects
1:05:41
from the surrounding cosmic web pulling outward on them. This
1:05:45
creates what physicists call a gravitational potential, well but inverted.
1:05:52
Instead of falling into a region of high density, matter
1:05:56
inside a void is being pulled toward the edges. The result,
1:06:02
the expansion rate inside voids differs from the expansion rate
1:06:07
in denser regions. Not by much. We're talking about differences
1:06:12
that require extraordinarily precise measurements to detect, but those differences
1:06:18
compound over cosmic time scales and distances. This creates a
1:06:23
problem a significant one. When we measure the Hubble constant,
1:06:28
the number that tells us how fast the universe is expanding,
1:06:33
we get different answers depending on how we measure it.
1:06:38
Observations of distant supernovae give one value, the cosmic microwave
1:06:44
background gives another. These measurements should agree, they don't. This
1:06:51
discrepancy is called the Hubble tension, and it's one of
1:06:55
the biggest unsolved problems in modern cosmology. What if the
1:07:00
tension isn't caused by measurement error or new physics. What
1:07:05
if it's because we're sitting inside a void. The KBC supervoid,
1:07:10
named after the astronomers who studied it, is roughly one
1:07:14
to two billion light years in diameter. Observations suggest the
1:07:19
Milky Way lies somewhere near its center. This isn't a
1:07:23
small feature. It's one of the largest under densities in
1:07:27
the observable universe. If we're inside such a structure, our
1:07:33
local measurements of cosmic expansion would be skewed. The void
1:07:38
acts like a lens, distorting our view of the universe
1:07:42
beyond it. Galaxies inside experience a different expansion rate than
1:07:48
the cosmic average. Think of it as living in a
1:07:52
valley and trying to measure the height of the surrounding mountains.
1:07:57
Your perspective is fundamentally based by your location. You're not
1:08:03
seeing the landscape from a neutral vantage point. Some researchers
1:08:07
propose this explains the Hubble tension entirely. The supernova we
1:08:12
observe are mostly within or near the KBC supervoid, giving
1:08:17
us a local measurement. The cosmic microwave background samples the
1:08:22
entire universe, giving us the global average different regions, different
1:08:29
expansion rates, different numbers. This would be convenient, it would
1:08:35
resolve a major cosmological crisis without requiring new physics or
1:08:41
exotic explanations. But it creates a philosophical problem that's arguably
1:08:46
worse than the measurement discrepancy. If our location inside a
1:08:51
void significantly affects our observations, then we're not seeing a
1:08:56
representative sample of the universe. Measurements are biased by cosmic geography.
1:09:03
The laws of physics we derive from local observations might
1:09:07
not accurately describe the cosmos as a whole. This undermines
1:09:12
a fundamental assumption in cosmology, the cosmological principle, The idea
1:09:18
that the universe looks roughly the same everywhere if you
1:09:21
zoom out far enough that there's no special location, no
1:09:26
privileged perspective. Living inside one of the largest voids in
1:09:31
the observable universe suggests we might occupy a rather unusual location,
1:09:36
after all, not special in any meaningful sense. The void
1:09:42
didn't form because we're here. We're not at the center
1:09:46
by design. Pure coincidence places us in this particular region
1:09:51
of space time. But coincidence or not, our location matters.
1:09:58
It affects what we can observe and how we interpret
1:10:01
those observations. Consider the implications. If the KBC supervoid significantly
1:10:08
influences our measurements, then our entire cosmological model might need adjustment.
1:10:15
The parameters we've carefully calibrated, the confidence we've built in
1:10:20
our understanding of dark energy and cosmic expansion, all potentially
1:10:25
compromised by location bias. We can try to correct for this,
1:10:31
account for our position inside a void when analyzing data,
1:10:36
adjust our models to compensate for local effects. But that
1:10:40
assumes we know the void's exact size, shape, and density profile.
1:10:46
We don't. Not precisely mapping the three dimensional structure of
1:10:52
cosmic voids requires extensive observation and complex analysis. Current surveys
1:10:59
are wa working on this, but we're still refining the details. Meanwhile,
1:11:05
dark energy continues its work, the KBC supervoid continues expanding,
1:11:12
the cosmic web continues fragmenting, and we're left wondering whether
1:11:17
our measurements reflect universal truths or local circumstances. This uncertainty
1:11:24
extends beyond just the Hubble constant. Any observation that depends
1:11:29
on distance, measurements, or expansion rates could be affected. The
1:11:34
age of the universe, the density of dark energy, the
1:11:39
timeline of cosmic structure formation not catastrophically wrong. The corrections
1:11:45
wouldn't be enormous, but significant enough to matter when we're
1:11:49
trying to understand the universe's fundamental nature with precision. There's
1:11:55
also the Eridanus supervoid to consider. Located about two two
1:12:00
billion light years away, it's even larger than the KBC Void,
1:12:05
roughly one point eight billion light years across. One of
1:12:09
the biggest structures ever detected, this void has its own
1:12:14
peculiar signature. It's associated with the CMB cold spot, an
1:12:20
anomalously cold region in the cosmic microwave background. The spot
1:12:25
is about seventy microkelvins colder than average. Doesn't sound like much,
1:12:30
but in the incredibly uniform CMB it stands out dramatically.
1:12:36
At some points, the cold spot is one hundred forty
1:12:40
microkelvins below average. That's far colder than random fluctuations should produce.
1:12:46
The Erdanus supervoid might explain this. As CMB photons pass
1:12:52
through such a massive under density, they lose energy climbing
1:12:56
out of the gravitational potential. This that creates a cold
1:13:00
spot in the background radiation. Except the math doesn't quite work.
1:13:06
The void isn't quite massive enough to produce the observed
1:13:10
temperature deficit, not by conventional physics anyway. So we're left
1:13:16
with options. Either there's something unusual about the Erdanus supervoid
1:13:21
that we don't understand, or the cold spot has a
1:13:24
different explanation entirely, or our understanding of how voids affect
1:13:29
the CMB needs refinement. Each possibility opens new questions, each
1:13:36
suggests gaps in our cosmic comprehension. These aren't small voids.
1:13:43
They're not local anomalies we can easily dismiss. They're fundamental
1:13:48
features of large scale structure, and they're challenging our ability
1:13:53
to interpret observations accurately. The problem compounds when you consider
1:14:00
that we can only observe voids in detail out to
1:14:04
a certain distance. Beyond that, they become difficult to map precisely.
1:14:11
We can infer their presence from how they affect visible structures,
1:14:16
but direct measurement becomes increasingly uncertain. This means our catalog
1:14:22
of cosmic voids is incomplete. We know they exist throughout
1:14:26
the observable universe, we know they dominate the volume of space,
1:14:32
but we can't map everyone, can't measure every effect, can't
1:14:37
fully account for how they influence our observations. It's like
1:14:42
trying to understand ocean currents while only being able to
1:14:46
sample a few scattered locations. You can build a model,
1:14:51
make predictions, test hypotheses, but you're always aware that your
1:14:57
data is incomplete. Your perspective limited. Voids represent the majority
1:15:03
of cosmic volume, but contain almost none of the matter.
1:15:07
This creates a strange inversion. In astronomy, we spend most
1:15:12
of our time studying the rare, dense regions where galaxies cluster,
1:15:17
because that's where the light is. That's what we can
1:15:21
observe directly. The voids remain mysterious, not for lack of interest,
1:15:27
but because emptiness is hard to study. You can't point
1:15:31
a telescope at nothing and expect to learn much. Instead,
1:15:36
we observe the boundaries, map the edges where voids meet filaments,
1:15:42
study the few galaxies that exist in void interiors. Watch
1:15:47
how light from distant sources bends as it passes through
1:15:50
these under dense regions. From these indirect observations, we reconstruct
1:15:57
void properties, infer their shape, apes, their expansion rates, their
1:16:02
effects on cosmic evolution. But there's always uncertainty, always the
1:16:09
possibility that we're missing something important because we're observing from
1:16:15
inside the structure. We're trying to understand. This is the
1:16:20
fundamental challenge of cosmology. We have one vantage point, one
1:16:25
moment in cosmic history, one set of observable phenomena. From
1:16:30
this limited perspective, we're attempting to understand the entire universe,
1:16:35
across all of space and time. Voids make this harder.
1:16:41
They introduce spatial variation in cosmic properties. They create regions
1:16:46
where expansion behaves differently. They affect light propagation in ways
1:16:52
we're still working to fully understand and they're winning, slowly
1:16:58
separating everything, creating more and more isolated pockets, where future
1:17:04
observers will have even less information to work with than
1:17:08
we do. You might think technology will save us. Better telescopes,
1:17:14
more sensitive detectors, more sophisticated analysis techniques. Surely we can
1:17:20
overcome these limitations with sufficient ingenuity. But there are hard limits.
1:17:26
Light speed is absolute, the cosmic horizon is real. Information
1:17:32
beyond certain distances is permanently inaccessible, not because our instruments
1:17:38
are inadequate, but because the universe's structure prevents that information
1:17:43
from ever reaching. US. Voids enforce these limits. Their expansion
1:17:48
pushes regions of space beyond our observable reach. The information.
1:17:53
Those regions contain, the galaxies, they host, the structures they form,
1:17:59
all loss to observation, not destroyed, but separated from us
1:18:04
by expanding space. This is already happening, has been happening
1:18:09
for billions of years, will continue happening for billions more.
1:18:14
Every second, some region of space crosses the threshold from
1:18:18
observable to forever hidden, The cosmic horizon shrinks, The observable
1:18:24
universe becomes smaller in terms of what we can causily access,
1:18:29
even as space itself continues expanding, Voids drive this process.
1:18:35
In dense regions matters, gravity partially counteracts cosmic expansion. Structures
1:18:41
can remain gravitationally bound even as space expands around them,
1:18:46
but voids have no such anchor. Nothing holds them together.
1:18:52
Dark energy pushes unopposed, stretching space faster and faster. The
1:18:58
question becomes how how much of the universe have we
1:19:01
already lost? How many galaxies have receded beyond the cosmic horizon?
1:19:07
How much structure has expanded away from us faster than
1:19:10
light can travel. We can calculate this. The math is straightforward,
1:19:17
The results are sobering. Most of the universe is already
1:19:20
beyond our reach. The observable universe represents a tiny fraction
1:19:26
of the total cosmos. Everything beyond about forty six billion
1:19:31
light years is causally disconnected from us. We will never
1:19:36
receive signals from those regions, never observe what happens there,
1:19:41
never confirm whether the same physical laws apply. Voids occupy
1:19:47
most of that invisible volume, vast empty regions we can
1:19:51
never map, never study, never understand in detail, And the
1:19:57
boundary keeps moving, keeps shrinking, keeps cutting us off from
1:20:02
more and more of cosmic reality. This isn't speculation, This
1:20:07
is direct consequence of measured expansion rates and well established physics.
1:20:12
The universe we can observe is temporary, The information we
1:20:16
can access is finite. The window for cosmic archaeology is closing.
1:20:22
Not quickly, not on human time scales, but inevitably. Future civilizations,
1:20:29
if they exist, will inherit a darker cosmos, fewer visible galaxies,
1:20:35
less accessible information, a smaller observable universe, despite living in
1:20:40
the same expanding space we inhabit now. They'll have to
1:20:44
trust our records, our measurements, our observations made during this
1:20:50
brief era when the cosmic web was still visible and
1:20:54
the universe's large scale structure could still be mapped. Assuming
1:21:00
those records survive, assuming future beings can interpret them correctly,
1:21:07
assuming the information doesn't get lost in the vast stretches
1:21:10
of time between now and then. Voids guarantee this future.
1:21:15
Their expansion is inexorable. Dark energy shows no signs of weakening.
1:21:22
The cosmic web will fragment, the observable universe will shrink,
1:21:28
Information will be lost. We're documenting what we can while
1:21:32
we can building catalogs of galaxies, mapping voids, measuring expansion rates,
1:21:40
recording everything before it disappears beyond the horizon. But we
1:21:45
know we're in a race we can't win. The universe
1:21:48
is larger than our ability to observe it. Voids are
1:21:52
expanding faster than we can map them. Cosmic structure is
1:21:57
fragmenting faster than we can document it. All we can
1:22:01
do is observe, measure, record, and hope that what we
1:22:06
learn now remains useful later when direct conformation becomes impossible.
1:22:13
Yet within these vast empty regions exist something stranger than
1:22:17
absence itself. Galaxies in voids aren't like galaxies elsewhere. They've evolved,
1:22:24
differently aged, differently developed characteristics that challenge our understanding of
1:22:31
how galaxies form. These void galaxies live in isolation, no
1:22:36
neighbours for millions of light years, no gravitational interactions pulling
1:22:41
at their structures, no mergers disrupting their evolution, just slow,
1:22:47
solitary existence in the emptiness between filaments. The boat's void
1:22:54
contains about sixty such galaxies, scattered across its two hundred
1:22:59
million light years radius, like forgotten islands in an ocean
1:23:03
of space. Each one represents a puzzle astronomers are still
1:23:07
trying to solve why do they exist at all. Standard
1:23:12
galaxy formation theory suggests galaxies need density material to collapse,
1:23:19
gravitational wells deep enough to pull gas and dark matter together.
1:23:25
Voids lack these conditions. They're defined by their absence of mass.
1:23:30
Yet void galaxies persist. They tend to be smaller than average,
1:23:35
bluer in color, indicating younger stellar populations, more gas rich,
1:23:42
suggesting active star formation, less evolved overall compared to galaxies
1:23:47
in denser environments. This makes sense on one level. Isolated
1:23:53
galaxies avoid the interactions that strip away gas and shut
1:23:57
down star formation. They maintain steady, uninterrupted growth over cosmic time.
1:24:05
But it raises another question. How did they form in
1:24:08
the first place. Current theories suggests they condensed from slight
1:24:13
over densities in the early universe, tiny fluctuations that managed
1:24:19
to overcome void expansion and collapse into galaxies, statistical outliers
1:24:25
that beat the odds. Once formed, they continued evolving in
1:24:29
their lonely environments. No harassment from neighbours, no tidal stripping,
1:24:36
no ram pressure from hot intracluster gas, just gradual, peaceful
1:24:41
star formation fueled by pristine gas infall. These galaxies provide
1:24:47
laboratories for studying galactic evolution in its purest form, no
1:24:52
environmental effects complicating the picture, no interactions distorting their structures, gravity,
1:25:01
gas dynamics, and star formation. Operating without interference, observations reveal
1:25:08
fascinating details. Void galaxies rotate differently than their counterparts in
1:25:15
dense regions. Their stellar populations show distinct age distributions. Their
1:25:22
chemical compositions tell stories of isolated enrichment. Some contain unusually
1:25:28
high proportions of dark matter. Their rotation curves suggest dark
1:25:33
matter halos that extend far beyond visible stellar discs. This
1:25:39
makes sense given their formation history in low density regions
1:25:43
where dark matter dominates. Others show signs of past activity,
1:25:49
ancient bursts of star formation followed by long quiescent periods,
1:25:55
suggesting their evolution proceeded in fits and starts rather than
1:25:59
st deady progression. The few galaxies that exist in supervoids
1:26:04
like Booteras represent extreme cases. They've spent billions of years
1:26:10
in regions where cosmic expansion dominates completely, where even the
1:26:15
small gravitational influences present in typical voids barely exist. These
1:26:22
galaxies challenge our understanding of minimum conditions for galaxy formation.
1:26:28
They demonstrate that galaxies can form and persist even in
1:26:32
the most hostile environments imaginable for structure formation, but their
1:26:38
isolation makes them difficult to study. Distance presents obvious challenges.
1:26:45
Low luminosity compounds the problem. Many void galaxies remain too
1:26:50
faint for detailed spectroscopy with current instruments. What we have
1:26:56
learned suggests their windows into cosmic history, preserved examples of
1:27:01
galaxy evolution without environmental influence, natural experiments showing what happens
1:27:08
when gravity alone shapes galactic destiny. Their existence also highlights
1:27:13
something profound about void structure. Voids aren't completely empty, not
1:27:19
even supervoids. They contain gas, dark matter radiation, just far
1:27:25
less than elsewhere. This minimal matter content follows the large
1:27:30
scale structure laid down by initial quantum fluctuations. Even in voids.
1:27:35
Density variations exist smaller subvoids within larger voids, filamentary structures
1:27:43
on reduced scales, a hierarchical pattern repeating across all size ranges.
1:27:50
Simulations reveal this complexity. High resolution models show voids containing
1:27:56
internal structure, mini walls, tiny fillis regions of slight over
1:28:02
density where void galaxies preferentially form. The cosmic web extends
1:28:08
even into voids themselves, just at lower amplitude, fainter, more subtle,
1:28:14
but present. Nonetheless, this hierarchical structure matters for understanding void expansion.
1:28:21
It's not uniform empty space expanding uniformly. It's a complex
1:28:26
environment where expansion rates vary depending on local density. In
1:28:32
the very emptiest regions, expansion proceeds fastest. Dark energy dominates completely,
1:28:40
space stretches at maximum rate allowed by cosmic expansion. In
1:28:45
slightly denser regions, matter provides small gravitational resistance, not enough
1:28:51
to prevent expansion, just enough to slow it marginally compared
1:28:56
to the emptiest areas. Over time, this differential expansion amplifies
1:29:02
existing density contrasts. The emptiest regions become emptier, the slightly
1:29:09
denser regions become relatively denser. By comparison, void structure evolves changes,
1:29:17
develops more pronounced internal features as expansion continues. This evolution
1:29:23
affects the few galaxies living inside voids as space expands
1:29:28
around them. Their isolation increases. Neighbours that were merely distant
1:29:34
become unreachably far. The universe fragments on progressively smaller scales. Eventually,
1:29:43
even void galaxies will lose sight of each other. Expansion
1:29:47
will carry them beyond each other's cosmic horizons. They'll become isolated,
1:29:53
not just spatially, but causially, forever alone in their expanding
1:29:58
bubbles of space. This fate awaits all cosmic structure eventually,
1:30:05
but void galaxies will experience it first. They're the vanguard
1:30:10
of cosmic isolation preview of what awaits all galaxies given
1:30:15
sufficient time. The timeline varies. Void galaxies in supervoids might
1:30:21
lose contact with neighbours within tens of billions of years.
1:30:26
Galaxies in denser regions could maintain visibility for hundreds of
1:30:30
billions of years. But the outcome remains identical isolation, darkness,
1:30:38
expanding emptiness between all structures. This brings us back to
1:30:43
the fundamental nature of voids themselves. They're not aberrations, not
1:30:48
unusual features that somehow formed despite cosmic uniformity. Their integral
1:30:54
components of large scale structure. Necessary consequences of how gravity
1:31:00
and expansion interact the cosmic web requires voids matter concentrating
1:31:06
in filaments must come from somewhere. That somewhere is voids.
1:31:12
They're the source regions that supplied material to denser areas.
1:31:17
During cosmic history's early phases, matter flowed out of low
1:31:21
density regions into high density ones. Gravity pulled material toward
1:31:27
over densities. Expansion pushed matter away from under densities. The
1:31:33
combination created the foam like structure we observe. Voids represent
1:31:38
those under densities grown to cosmic proportions, regions where outflow
1:31:44
exceeded inflow, where expansion overcame gravity, where emptiness won. This
1:31:51
process continues today. Matter still flows out of voids toward filaments.
1:31:57
The process has slowed as expansion accelet, but it hasn't stopped.
1:32:03
Voids still drain still feed material to surrounding structures, still
1:32:09
expand and empty themselves further. The difference now is dark
1:32:13
energy's dominance. Early in cosmic history, matter density was higher,
1:32:19
gravity stronger, expansion slower. Voids formed, but grew gradually. Now,
1:32:26
with dark energy driving accelerated expansion, voids grow faster. Their
1:32:32
expansion rate increases. Over time, the drainage process accelerates. This
1:32:38
acceleration has profound implications for future structure. The cosmic web
1:32:43
we observe represents a temporary phase, a brief era when
1:32:48
structure was visible before void expansion tears it apart. In
1:32:53
the deep future, voids will dominate completely. They'll occupy most
1:32:58
of space volume, most of the universe's geography. Dense regions
1:33:04
will exist as scattered islands isolated galaxy clusters separated by
1:33:10
vast expanding emptiness. Each cluster causially disconnected from all others.
1:33:16
Within those islands, local physics continues, stars form and die,
1:33:22
Galaxies orbit each other, Gravity operates normally, but beyond the
1:33:28
cluster boundaries exponentially expanding void. From inside such a cluster,
1:33:34
the universe would appear dramatically different than today, no distant
1:33:39
galaxies visible, no cosmic web structure, no evidence of expansion
1:33:45
beyond the local group. Observations would show only nearby galaxies
1:33:50
bound by gravity. Everything else would have receded beyond the
1:33:55
cosmic horizon, disappeared into expanding void. Astronomers in that era
1:34:01
would face impossible challenges reconstructing cosmic history. No access to
1:34:07
distant light, no ability to observe early universe, no evidence
1:34:13
of the Big Bang, beyond local thermal radiation. They'd have
1:34:17
to trust ancient records, measurements made during the current era
1:34:22
when observation was still possible, assuming those records survived billions
1:34:28
of years of cosmic time. This scenario isn't speculation. It's
1:34:34
the predictable outcome of measured expansion rates and well established cosmology.
1:34:40
The math is straightforward the conclusions unavoidable voids will consume
1:34:46
the observable universe, not by destroying structures, by separating them
1:34:52
beyond the distance light can travel, by expanding space faster
1:34:56
than causality can propagate. The process has already begun. Already,
1:35:04
galaxies are receding beyond our cosmic horizon. Already information is
1:35:10
being lost. Already, the observable universe shrinks in terms of
1:35:15
accessible content. We're living in a golden age of cosmology,
1:35:20
an era when the universe's large scale structure remains visible,
1:35:25
when we can still observe the cosmic web, still map voids,
1:35:30
still measure expansion across cosmic time. This window won't remain open.
1:35:37
Current estimates suggest we have perhaps one hundred billion years
1:35:41
before distant galaxies fade from view, before void expansion carries
1:35:46
them beyond observation. That sounds like plenty of time, and
1:35:51
it is by human standards, but it's brief on cosmic scales,
1:35:57
a tiny fraction of the universe's total lifetime, a momentary
1:36:02
window when comprehensive observation remains possible. After that window closes,
1:36:09
voids will have effectively swallowed the universe, not through destruction,
1:36:14
through separation, by expanding space until structures become causially isolated.
1:36:22
The universe will still exist, Galaxies will still shine, stars
1:36:27
will still burn, but in isolation, each structure alone in
1:36:32
its expanding bubble, unable to observe or influence anything beyond
1:36:37
its local gravitational domain. This represents the ultimate triumph of
1:36:42
void expansion, the final consequence of dark energy's dominance, the
1:36:49
inevitable end point of accelerated cosmic expansion. Voids started as
1:36:55
slight under densities statistical fluctuations in the early year universe
1:37:00
is matter distribution. They grew through gravitational drainage and cosmic expansion,
1:37:07
evolved into the massive empty regions we observe today, and
1:37:12
they'll continue growing, continue expanding, continue separating structures until isolation
1:37:19
becomes complete. We can observe this process, measure it, calculate
1:37:25
its progression. But we cannot stop it, cannot reverse, it
1:37:30
cannot prevent the fragmentation it will cause. All we can
1:37:35
do is document what we observe while observation remains possible.
1:37:40
Map the cosmic web before it fragments. Measure void expansion
1:37:46
before it carries everything beyond reach. Record the universe's large
1:37:51
scale structure before that structure becomes invisible, because eventually, voids
1:37:57
will hide everything, conceal the universe's true scope behind horizons
1:38:03
of expanding space, transform the rich cosmic landscape into isolated
1:38:09
islands separated by unbridgable distances. The terrifying void isn't a
1:38:15
single structure. It's the collective future of all voids, the
1:38:20
eventual state toward which cosmic expansion drives us a universe
1:38:26
fractured by emptiness, separated by space expanding faster than light
1:38:31
can cross it. That future becomes clearer as we examine
1:38:36
what dark energy actually does. Dark energy doesn't behave like
1:38:40
normal forces. It doesn't weaken with distance, doesn't diminish as
1:38:45
space expands. Instead, it maintains constant density throughout space. As
1:38:52
the universe grows more space appears, and that new space
1:38:57
carries the same dark energy density as the old space.
1:39:01
Think about what this means. Normal matter gets diluted by expansion.
1:39:07
Galaxies spread farther apart, their gravitational influence on each other weakens,
1:39:13
but dark energy grows stronger in total effect because there's
1:39:18
more space for it to occupy. This is why voids
1:39:21
expand so effectively their regions where dark energy dominates completely.
1:39:28
Where matter is too sparse to provide meaningful gravitational resistance,
1:39:34
the expansion isn't fighting against anything substantial, it's just stretching space.
1:39:40
According to dark energy's inherent properties, we can measure this
1:39:45
effect directly. Observations show the universe's expansion rate increasing over time,
1:39:53
not slowing down as gravity would predict, accelerating getting faster
1:40:00
with each passing billion years. This acceleration started roughly five
1:40:05
billion years ago. Before that, the universe's expansion was decelerating.
1:40:11
Gravity was winning the cosmic tug of war. Matter density
1:40:15
was high enough that gravitational attraction slowed expansion, But as
1:40:20
expansion continued, matter spread thinner, its gravitational influence weakened, and
1:40:27
dark energy maintaining constant density. Eventually took over. The transition
1:40:34
marked a fundamental shift in cosmic evolution. Since then, dark
1:40:39
energy has driven everything, shaped the universe's fate, determined how
1:40:45
structures evolve, and guaranteed that voids would eventually dominate the
1:40:50
cosmic landscape. The mathematics are straightforward. Dark energy contributes roughly
1:40:56
sixty eight percent of the universe's total mass energy content.
1:41:01
Dark matter adds another twenty seven percent. Normal matter everything
1:41:06
we can see and touch makes up just five percent.
1:41:11
Those percentages tell a story. The universe is fundamentally made
1:41:16
of things we don't understand. Dark energy and dark matter
1:41:21
completely dominate. Ordinary matter is almost an afterthought in the
1:41:27
cosmic budget. But here's what makes dark energy particularly strange.
1:41:33
It behaves like Einstein's cosmological constant, a property of space
1:41:39
itself rather than something in space. Every cubic meter of
1:41:44
vacuum carries the same amount of dark energy, regardless of
1:41:48
what else occupies that region. Einstein originally introduced the cosmological
1:41:53
constant to keep the universe static. He thought gravity would
1:41:58
cause collapse and added repulsive term to balance it. When
1:42:03
Hubble discovered cosmic expansion, Einstein called the constant his greatest blunder,
1:42:10
except it wasn't a blunder. It was prescient. The cosmological
1:42:15
constant appears to be real. It's just not serving the
1:42:18
purpose Einstein intended. Instead of preventing collapse, its driving acceleration,
1:42:26
pushing the universe toward eternal expansion. Recent observations from the
1:42:32
Dark Energy Spectroscopic Instrument add another layer of complexity. Deesi's
1:42:39
data suggests dark energy might not be constant after all.
1:42:44
Its strength may have changed over cosmic time. The measurements
1:42:49
indicate dark energy was stronger in the past, had a
1:42:53
parameter value below negative one point four billions of years ago.
1:42:58
That value has gradually increase to around negative zero point
1:43:03
eight today. If confirmed, this changes everything. It means dark
1:43:09
energy isn't a simple cosmological constant. It's a dynamic field
1:43:14
that evolves, something more complex than Einstein's original concept. This
1:43:20
possibility terrifies cosmologists and excites them in equal measure. A
1:43:26
constant dark energy leads to predictable expansion eternal acceleration at
1:43:33
a steady rate, but evolving dark energy introduces uncertainty about
1:43:39
the universe's ultimate fate. If dark energy continues, weakening, expansion
1:43:45
might eventually slow, perhaps even reverse, The Big Crunch scenario
1:43:51
becomes possible again, all matter eventually collapsing back together in
1:43:56
a reversal of the Big Bang. Alternatively, if dark energy strengthens,
1:44:02
expansion could accelerate beyond control the Big Rip scenario, space
1:44:08
expanding so rapidly it tears apart galaxies, stars, planets eventually
1:44:15
atoms themselves. Current data doesn't definitively favor either extreme, but
1:44:21
it suggests dark energy's behavior is more subtle than we assumed,
1:44:27
more interesting, and potentially more consequential for cosmic evolution. This
1:44:33
uncertainty doesn't change void expansion's current trajectory. Dark energy is
1:44:39
driving voids larger, regardless of its precise nature. The process
1:44:45
continues whether the force remains constant or evolves gradually, but
1:44:50
it affects our understanding of time scales. How quickly voids
1:44:55
will isolate structures, how long the cosmic web will remainane
1:45:00
observable when the universe transitions to its final state. The
1:45:05
mechanism of void expansion itself remains clear. Dark energy creates
1:45:11
negative pressure throughout space. This pressure pushes outward in regions
1:45:17
where matter provides gravitational resistance. The effect is subtle, but
1:45:23
in voids, where resistance is minimal, expansion proceeds unimpeded. You
1:45:29
can visualize this as stretching a rubber sheet. Dense regions
1:45:34
are like weights placed on the sheet. They resist stretching
1:45:38
locally create dimples in the fabric, but between the weights,
1:45:43
the sheet stretches freely. Voids are those regions between weights
1:45:49
where space expands most efficiently, where dark energy's influence manifests
1:45:55
most directly. The expansion doesn't add matter to voids. It
1:46:00
doesn't create new galaxies or fill empty regions. It simply
1:46:05
increases the distance between whatever matter already exists. Spread structures
1:46:10
farther apart creates more emptiness between islands of mass. This
1:46:16
process is irreversible under current physics. Once space expands beyond
1:46:22
a certain point, no force can bring separated structures back together.
1:46:28
Light from one can never reach the other, Gravitational influence
1:46:33
becomes impossible. Causal connection breaks permanently. Where watching this happen
1:46:39
in real time, not dramatically. The changes occur over millions
1:46:45
and billions of years, but they're happening measurable, predictable based
1:46:51
on known physics. Distant galaxies are already receding faster than light.
1:46:57
Not moving through space at superluminminal speeds which relativity forbids,
1:47:03
but carried by space expansion, the space between us and
1:47:08
them grows faster than photons can traverse it. These galaxies
1:47:13
haven't disappeared yet. Light they emitted billions of years ago
1:47:17
is still reaching us. We see them as they were
1:47:21
when the universe was younger, when expansion hadn't yet carried
1:47:26
them beyond the cosmic horizon. But eventually that ancient light
1:47:31
will be all we can receive. No new information will arrive.
1:47:37
The galaxies will freeze in observational time, visible forever in principle,
1:47:43
but showing only their ancient state. Then even that frozen
1:47:47
image will fade red, shifted to longer and longer wavelengths,
1:47:52
dimmer and dimmer until it drops below any possible detection threshold.
1:47:58
This is how voids can assume the observable universe, not
1:48:02
through destruction, but through separation, by expanding space until light
1:48:09
can no longer bridge the distances involved. The process affects
1:48:13
different structures at different rates. Galaxies within clusters remain gravitationally bound.
1:48:21
Their mutual gravity overcomes local expansion. They stay together even
1:48:27
as space stretches around them, but clusters themselves will eventually separate.
1:48:33
The space between them will expand beyond gravitational influence. Each
1:48:38
cluster will become isolated, a island universe alone in expanding void.
1:48:45
Within those islands, galaxies might merge, collide, and combine due
1:48:51
to their orbital motions. Over trillions of years, each cluster
1:48:55
could coalesce into a single massive galaxy, the last structure
1:49:00
formation event before eternal isolation. That single galaxy would contain
1:49:05
all the matter from its original cluster, billions of stars,
1:49:10
vast reserves of gas and dust, black holes, nebulai, all
1:49:16
the components of galactic structure, but nothing beyond, No neighboring galaxies,
1:49:23
no cosmic web, just emptiness expanding forever in all directions.
1:49:29
Beings living in such a galaxy would face profound observational limitations.
1:49:34
Their entire observable universe would consist of one galaxy. Everything
1:49:40
beyond would have receded past the cosmic horizon. They could
1:49:44
study their own galaxy in detail, map its stars, understand
1:49:50
local physics, but cosmology as we know it would be impossible.
1:49:55
No way to observe the universe's large scale structure, no
1:50:00
evidence of the Big Bang beyond local thermal radiation. Their
1:50:05
scientists would have to rely on theoretical models, ancient records,
1:50:10
if any survived, mathematical predictions, rather than direct observation, a
1:50:17
fundamentally different scientific enterprise than what we practice to day.
1:50:22
This scenario isn't science fiction. It's the predicted state of
1:50:27
the universe in the distant future, based on measured expansion
1:50:32
rates and well established physical laws. The math is clear,
1:50:38
the conclusions unavoidable. Some researchers have proposed this might already
1:50:44
be affecting our observations. The KBC Void, a massive under
1:50:50
density roughly one to two billion light years across, may
1:50:55
contain our galaxy near its center. If we're inside a supervoid,
1:51:00
local expansion rates could differ from cosmic averages. This might
1:51:05
explain the Hubble tension, the discrepancy between different methods of
1:51:09
measuring the universe's expansion rate. Measurements using nearby supernovae yield
1:51:16
values around seventy two to seventy five kilometers per second
1:51:20
per megaparsec, but measurements from the cosmic microwave background give
1:51:26
sixty seven to sixty eight The difference seems small, but
1:51:31
its statistically significant, a real problem for cosmology. Living inside
1:51:37
a void could account for this. Galaxies within voids experience
1:51:43
gravitational pull from denser regions outside. This affects their motion,
1:51:49
creates apparent expansion rates that differ from the universal average.
1:51:55
It's like measuring ocean currents from insider whirlpool. The local
1:52:00
motion doesn't represent the ocean's overall flow. You're in a
1:52:05
special region where dynamics differ from the norm. This possibility
1:52:10
highlights how voids affect everything, not just future cosmic evolution,
1:52:16
but current observations, our measurements, our understanding of fundamental cosmology.
1:52:23
If we're in a void, we need to account for
1:52:26
that in our models, adjust our measurements, recognize that local
1:52:32
observations might not represent universal conditions. The implications extend beyond
1:52:38
resolving measurement discrepancies. They affect our understanding of dark energy itself,
1:52:45
how strongly it pushes, how it has evolved over time,
1:52:50
what it predicts for the future. Void server as natural
1:52:55
laboratories for studying dark energy regions where it's effects dominate,
1:53:01
where we can observe its influence without gravitational complications. From
1:53:06
dense matter. By mapping void expansion rates, we learn about
1:53:11
dark energy's properties, how it behaves in different cosmic environments,
1:53:16
whether its strength varies with location or time. These studies
1:53:21
reveal patterns. Voids expand at predictable rates based on their
1:53:26
size and the surrounding matter distribution. Larger voids grow faster.
1:53:33
Isolated voids expand more efficiently than those adjacent to dense structures.
1:53:40
The expansion follows mathematical relationships power laws, describing how void
1:53:46
size increases with cosmic time. These relationships match predictions from
1:53:52
dark energy models, confirming that we understand the basic physics.
1:53:57
But puzzles remains. Dark energy have its observed strength, Why
1:54:03
not stronger or weaker? The value seems arbitrary, yet it
1:54:07
determines cosmic fate. If dark energy were slightly weaker, gravity
1:54:12
would dominate, the universe would eventually collapse. If slightly stronger,
1:54:19
expansion would have prevented structure formation, no galaxies, no stars,
1:54:26
no planets. We exist in a narrow range where dark
1:54:30
energy is strong enough to drive expansion but weak enough
1:54:34
to allow structure formation. This appears fine tuned, suspiciously well balanced.
1:54:43
Some physicists invoke the anthropic principle. We observe these values
1:54:48
because only universes with these properties produce observers in other
1:54:54
universes with different dark energy strengths. Nobody exists to ask
1:54:59
the ques question. Others suggest underlying physics, we haven't discovered
1:55:05
mechanisms that set dark energy strength based on fundamental principles
1:55:11
relationships between different forces that constrain possible values, the answer
1:55:17
remains unknown. Dark energy is the universe's biggest mystery, more
1:55:23
fundamental than dark matter, more consequential for cosmic evolution, and
1:55:29
voids are where dark energy does its work most effectively,
1:55:33
where we see its influence most clearly, where it shapes
1:55:37
the universe's ultimate structure. As expansion continues, voids will dominate
1:55:44
more completely, occupy larger fractions of space, press harder against
1:55:50
remaining structures. The cosmic web will fragment dissolve into isolated
1:55:57
components separated by unbridgeable ess. This future is certain unless
1:56:03
our understanding of physics is fundamentally wrong, Unless dark energy
1:56:09
behaves differently than observed, unless some unknown force intervenes. None
1:56:15
of those possibilities seem likely. Dark energy's effects are too
1:56:20
well measured, too consistent, across different observation methods, too thoroughly
1:56:26
integrated into cosmological models. We're watching the universe's transformation in progress,
1:56:33
observing the early stages of void domination, documenting the cosmic
1:56:39
web before it fragments beyond recognition. What makes this particularly
1:56:43
urgent is the limited observation window we have, perhaps one
1:56:48
hundred billion years before distant structures fade from view. That
1:56:53
sounds generous, but its brief cosmically. After that window closes,
1:56:59
comprehen tensive cosmology becomes impossible. Future observers will see only
1:57:05
their local region, everything else hidden beyond horizons of expanding space.
1:57:12
We're fortunate to live when observation remains possible, when the
1:57:16
cosmic web stretches across our sky, when we can still
1:57:21
map voids and measure their expansion. This era won't last,
1:57:26
and once it ends, this knowledge becomes inaccessible to direct observation.
1:57:31
The terrifying void isn't coming. It's already here, already expanding,
1:57:37
already separating structures. The process has been underway for billions
1:57:43
of years. We're just finally understanding what it means for
1:57:46
the universe's future. Understanding this reality changes how we see
1:57:52
our cosmic neighbourhood. We're not passive observers watching from safe distance.
1:57:59
We're participating in void expansion, part of the transformation happening
1:58:04
throughout the universe. Our galaxy sits within the KBC supervoid.
1:58:10
This massive under density stretches across two billion light years,
1:58:15
with US near its center. Living inside a void isn't
1:58:19
immediately obvious. Stars still shine overhead nearby galaxies remain visible,
1:58:26
but measurements reveal the truth. Galaxy density around US is
1:58:31
significantly lower than cosmic average. About thirty percent less matter
1:58:37
occupies our region compared to typical space. This deficit affects
1:58:42
everything from cosmic expansion measurements to our understanding of dark
1:58:47
energy strength. The KBC void explains puzzling observations why local
1:58:54
expansion measurements differ from distant ones, why some cosmic parameters
1:59:00
seem inconsistent across different methods. Our location inside this under
1:59:05
density skews our perspective. Galaxies inside voids experience peculiar gravitational
1:59:13
effects the surrounding matter distribution pulls outward. This creates additional
1:59:19
expansion beyond what dark energy alone produces. Local measurements therefore
1:59:26
yield higher expansion rates than global averages. This resolves the
1:59:31
Hubble tension partially. The discrepancy between local and distant expansion
1:59:36
measurements makes sense when accounting for void location, where measuring
1:59:42
expansion from within an under dense region. Of course, our
1:59:46
numbers differ from cosmic averages. But the KBC void raises
1:59:52
uncomfortable questions about cosmological assumptions. Standard models assume uniform matter distribution,
2:00:00
that we can measure universal properties from any location. Sitting
2:00:05
inside a supervoid violates this assumption. How many other measurements
2:00:11
are biased by our position? What cosmic truths remain hidden
2:00:16
because we're observing from inside emptiness? These questions challenge fundamental
2:00:22
cosmological principles. The Boater's Void offers even more dramatic perspective.
2:00:30
This spherical emptiness contains only sixty galaxies across two hundred
2:00:36
million light years. If our galaxy had formed there, human
2:00:41
astronomy would have developed very differently. Imagine looking up and
2:00:46
seeing almost nothing, a handful of faint smudges instead of
2:00:51
thousands of galaxies the cosmic microwave background, but little else
2:00:57
beyond our galactic neighborhood. This would have been our reality.
2:01:02
From Boater's void's center. We wouldn't have discovered the expanding
2:01:06
universe until recently, couldn't have mapped large scale structure, would
2:01:12
have assumed our galaxy represented the entire cosmos for most
2:01:15
of history. Only modern telescopes would have revealed the broader universe.
2:01:22
This thought experiment reveals how location determines knowledge. Cosmic understanding
2:01:28
depends on where you happen to form. Intelligence. Arising in
2:01:33
void centers faces different observational challenges than we do. They
2:01:39
would see emptiness as normal the default cosmic state. Dense
2:01:45
regions would seem exotic and unusual when finally discovered. Their
2:01:51
cosmology would develop from fundamentally different starting assumptions. What makes
2:01:57
voids truly terrifying isn't their current state, it's their relentless expansion.
2:02:03
These regions grow continuously, consuming more space, pressing harder against
2:02:09
remaining structures. The process never stops as long as dark
2:02:14
energy dominates. Computer simulations project this future with disturbing clarity.
2:02:21
Feed current observations into cosmological models, let time advance. Watch
2:02:27
what happens to the cosmic web over billions of years. Initially,
2:02:32
the changes seem subtle. Voids expand gradually, filaments thin slightly.
2:02:38
The overall structure remains recognizable, but continue the simulation forward.
2:02:45
The transformation accelerates by one hundred billion years from now,
2:02:50
distant galaxy clusters will have receded beyond observation. Their light
2:02:55
stretch to undetectable wavelengths, space between us and them expanding
2:03:01
faster than light can travel. They still exist, but become
2:03:05
permanently invisible. Local structures survive longer. Our galaxy cluster remains
2:03:12
gravitationally bound. Nearby groups stay visible, but the broader cosmic
2:03:18
context disappears. Future observers will see only their immediate neighbourhood,
2:03:25
everything else lost beyond unreachable horizons. Continue the simulation further.
2:03:32
One trillion years forward, the Milky Way and Andromeda have
2:03:36
long since merged formed a single elliptical galaxy. Most stars
2:03:42
have burned out. New formation has nearly ceased. The universe
2:03:47
grows darker. Other galaxy clusters drift in isolation, separated by
2:03:53
ever expanding voids, no communication possible between them. Each island
2:03:58
universe evolves independently, cut off from cosmic community by relentless expansion.
2:04:05
Push to one hundred trillion years stars have exhausted available gas.
2:04:11
No new stellar formation occurs anywhere. Existing stars gradually fade,
2:04:17
white dwarfs, cool neutron stars radiate away their heat. Black
2:04:22
holes accumulate surrounding matter. The voids dominate completely, occupy ninety
2:04:29
nine point nine to nine percent of space. Remaining matter
2:04:33
concentrates in tiny pockets islands of structure in an ocean
2:04:37
of emptiness. The cosmic web has dissolved entirely. Only isolated
2:04:43
remnants persist. At this point, void expansion becomes the universe's
2:04:48
defining characteristic structure. Formation belongs to ancient history. The cosmos
2:04:55
enters an era of dissolution. Remaining matter gradually disperse. Us
2:05:01
energy spreads thinner across expanding space. Eventually, even black holes
2:05:06
evaporate through Hawking radiation. This takes incomprehensible time scales ten
2:05:13
to the one hundred years numbers that dwarf cosmic age
2:05:17
by factors beyond comprehension, but given infinite time, even this occurs.
2:05:23
After black hole evaporation, essentially nothing remains a few scattered particles.
2:05:30
Photons stretch to wavelengths larger than galaxies, space expanding ever faster,
2:05:37
temperature approaching absolute zero. This is heat death, the universe's
2:05:44
final state under current physics. Some physicists propose alternatives. Maybe
2:05:50
dark energy will weaken, expansion could slow or reverse. The
2:05:56
universe might collapse in a big crunch, resetting can conditions
2:06:00
for another cosmic cycle. Or dark energy might strengthen, becoming
2:06:05
phantom energy that increases with expansion. This leads to the
2:06:10
big rip scenario, where acceleration becomes so extreme it tears
2:06:15
apart all structures. Galaxies, stars, planets eventually atoms themselves, space
2:06:23
time ripped to shreds. Current evidence suggests neither extreme seems likely.
2:06:30
Dark energy appears constant, the cosmological constant Einstein proposed. This
2:06:37
points toward heat death as the most probable outcome. Recent
2:06:42
observations add intriguing complexity. The Dark Energy Spectroscopic Instrument detects
2:06:49
hints that dark energy may vary with time, possibly stronger
2:06:53
in the past than now. If confirmed, this changes everything
2:06:58
about long term PRIs Evolving dark energy opens new possibilities.
2:07:05
Maybe it will decay eventually, allowing gravity to reassert dominance.
2:07:12
Structure formation could resume after a lengthy dormant period. The
2:07:17
universe might prove more dynamic than current models suggest these
2:07:22
remain speculative possibilities. Current observations favor constant dark energy heat
2:07:30
death through endless void expansion. But cosmology has surprised us repeatedly.
2:07:37
What seems certain often proves incomplete. What we know for
2:07:42
sure is that voids expand. Now this process continues unless
2:07:47
something dramatic changes, the cosmic web faces inevitable dissolution. On
2:07:53
time scales. We can calculate this isn't speculation, its observable
2:07:58
physics projected forward. Living during the observable era feels fortunate.
2:08:04
We can see the cosmic web intact map, large scale structure,
2:08:10
measure void expansion, understand how dark energy operates. Future observers
2:08:16
won't have this opportunity. In one hundred billion years, comprehensive
2:08:22
cosmology becomes impossible. Too much universe has receded beyond observation.
2:08:29
The cosmic microwave background will have red shifted beyond detection,
2:08:35
distant structures disappeared behind horizons. Only local measurements remain possible.
2:08:42
This creates a knowledge extinction event. Information about cosmic history
2:08:48
becomes permanently inaccessible. Future civilizations will face fundamental limits on
2:08:55
what they can discover about their Universe's origins and structure.
2:09:00
We exist in a brief window, perhaps two hundred billion
2:09:04
years total, when universe scale cosmology remains feasible. Before this window,
2:09:10
stars hadn't formed yet. After it closes, observation becomes too limited.
2:09:17
We're living in cosmology's golden age. This perspective makes current
2:09:22
astronomical research more urgent. We're documenting the universe while documentation
2:09:29
remains possible, recording the cosmic web before it fragments, Measuring
2:09:36
void expansion while voids still have defined boundaries. Every observation
2:09:41
contributes to this comprehensive record. Galaxy surveys mapping large scale structure,
2:09:49
void catalogs documenting emptiness, expansion measurements tracking dark energy's effects. Together,
2:09:57
these create a snapshot of the universe during its structured era.
2:10:02
The terrifying aspect isn't void emptiness itself. Empty space seems
2:10:07
peaceful quiet. The terror comes from irreversibility. This process cannot
2:10:14
stop under known physics, cannot reverse, cannot be prevented. We're
2:10:20
watching the universe's transformation from complexity to simplicity, from structure
2:10:27
to emptiness, from connection to isolation, and this transformation is
2:10:34
guaranteed unless our understanding of fundamental physics is wrong. Even
2:10:39
calling it terrifying might be projection. The universe doesn't care
2:10:44
about our esthetic preferences. Void's expanding is simply physics operating
2:10:50
as it must, dark energy doing what dark energy does,
2:10:56
the cosmos following its natural trajectory. Perhaps terror comes from
2:11:01
recognizing impermanence. The cosmic web we observe today is temporary,
2:11:09
like everything else in the universe. It formed from simpler
2:11:13
initial conditions. It will dissolve into simpler final states. We're
2:11:19
witness in the middle chapter, The expanding voids teach us
2:11:23
that structure is transient. Emptiness is permanent. Given enough time,
2:11:29
separation wins over connection, dispersal overcomes concentration. The universe trends
2:11:36
toward maximum entropy, toward heat death. But even this might
2:11:42
not be the end. Quantum fluctuations could eventually create new structures.
2:11:47
Given literally infinite time, new big bangs might emerge from
2:11:52
quantum vacuum, resetting the cycle. These possibilities extend beyond current
2:11:58
physics into speculation about what might happen on time scales
2:12:03
that make cosmic age seem instantaneous. We simply don't know
2:12:08
if the universe has tricks we haven't imagined. What we
2:12:11
can say is this, voids are expanding, The cosmic web
2:12:16
is fragmenting, structure. Formation era is ending. We're living through
2:12:21
a cosmic transition from the universe's middle age toward its
2:12:26
long decline. The process is measurable, inevitable, already underway. The
2:12:33
void isn't coming to swallow the universe. It's already here, growing, steadily,
2:12:40
claiming more space with each passing moment, separating galaxies that
2:12:45
will never reconnect, creating the isolation that defines the universe's
2:12:50
far future. And we're watching it happen, recording the transformation,
2:12:56
understanding the physics, documenting the cosmic web while it still
2:13:01
exists as an integrated whole. This makes us witnesses to
2:13:06
one of the universe's most significant transitions, from structure to void,
2:13:11
from connection to isolation, from complexity to simplicity. The terrifying
2:13:19
void is the Universe's destiny. We are living in a
2:13:23
universe that is forgetting itself. Every second, roughly twenty thousand
2:13:28
galaxies cross beyond the cosmic horizon. They're still out there somewhere,
2:13:34
still burning through their fuel, still hosting whatever structures or systems,
2:13:40
or perhaps even civilizations they contain, but their light will
2:13:45
never reach us again. The space between us expands faster
2:13:49
than photons can travel. These galaxies have become part of
2:13:54
a universe we can know exists but cannot observe. This
2:13:59
isn't some distance future catastrophe. It's happening right now, while
2:14:04
you've been reading this, while you've been breathing and thinking
2:14:09
and existing. The observable universe has become measurably smaller in
2:14:14
terms of what we can access, what we can study,
2:14:19
what we can ever hope to understand. The voids are winning,
2:14:25
not through any malicious intent, not through conscious effort, simply
2:14:30
through the relentless mathematics of expansion, dark energy pushing space
2:14:35
outward at an accelerating rate, creating more emptiness, more separation,
2:14:42
more isolation. In one hundred billion years, give or take,
2:14:48
the cosmic web will have dissolved from view. Future observers
2:14:53
will look up and see only their local galaxy cluster.
2:14:57
Everything else will have receded beyond the horizon. The universe
2:15:01
will appear smaller, darker, lonelier, not because it has become smaller,
2:15:08
but because observation has become impossible. Those future astronomers won't
2:15:14
be able to discover the Big Bang, won't have access
2:15:18
to the cosmic microwave background, won't be able to measure
2:15:22
universal expansion. All the evidence we use to build modern
2:15:26
cosmology will have literally moved beyond reach. They'll have to
2:15:31
trust records measurements made during our era, when observation was
2:15:36
still possible, assuming those records survive the immense stretches of
2:15:40
time between now and then, assuming they can be interpreted correctly,
2:15:46
assuming they're not dismissed as mythology. This is what voids do.
2:15:51
They don't destroy information, They separate it, place it beyond reach,
2:15:58
create permanent boundaries that even light cannot cross. We exist
2:16:03
in a privileged moment. The universe is old enough that
2:16:07
we've developed the technology to observe its large scale structure,
2:16:12
young enough that structure still exists to observe. This window
2:16:17
is temporary, brief on cosmic scales, and its closing. Every
2:16:23
observation we make now carries added weight. Every measurement contributes
2:16:29
to a record that future civilizations might never be able
2:16:33
to verify independently. We're documenting the universe during its observable era.
2:16:41
Recording what exists before it disappears behind horizons we cannot penetrate.
2:16:46
The Booter's Void contains sixty galaxies across two hundred million
2:16:51
light years. The Eridana Supervoid stretches one point eight billion
2:16:56
light years. The KBC voids surround us with reduced density
2:17:01
across two billion light years. These aren't anomalies. They're the
2:17:06
dominant features of cosmic structure. They occupy more volume than
2:17:12
all the filaments and clusters combined, and they're growing, pressing
2:17:17
against the cosmic web from all directions, stretching space faster
2:17:22
in their interiors than in denser regions, creating differential expansion
2:17:28
that will eventually fragment all large scale structure into isolated pieces.
2:17:35
The mathematics are clear, the physics well established. The outcome
2:17:41
inevitable unless something dramatic changes in our understanding of fundamental forces.
2:17:47
Dark energy dominates the cosmic budget sixty eight percent of
2:17:52
everything that exists. It doesn't dilute with expansion, maintains constant
2:17:58
density as space grows. This means total dark energy increases
2:18:02
as the universe expands. More space equals more push. More
2:18:07
push equals faster expansion, faster expansion creates more space, the
2:18:13
cycle accelerates itself. Voids provide the environment where this process
2:18:18
operates most efficiently, where matters gravitational resistance is minimal, where
2:18:25
dark energy can stretch space unimpeded, where the universe's future
2:18:30
is already visible. Looking at a void isn't just seeing emptiness.
2:18:36
It's seeing what awaits all of space, eventually, the final
2:18:40
state toward which expansion drives everything maximum entropy, heat death,
2:18:47
eternal isolation in ever expanding darkness. Some might find this depressing.
2:18:53
The inevitable dissolution of all structure, the fragmentation of the
2:18:58
cosmic web, the loss of observable universe, the approach of
2:19:03
heat death. But perhaps there's something else worth considering. We
2:19:08
are here now, during the observable era, able to see
2:19:13
the cosmic web, intact, able to map voids and measure
2:19:17
their expansion, able to understand what's happening and why we
2:19:23
are the universe becoming aware of its own transformation, conscious matter,
2:19:28
capable of observing cosmic evolution, temporary arrangements of atoms that
2:19:34
can contemplate their origins and fate. The voids are expanding,
2:19:40
the cosmic web is dissolving. Structure, formation is ending. These
2:19:46
are facts we cannot change, but we can observe, measure, understand, record,
2:19:56
pass forward the knowledge we gain during this brief window
2:20:00
when comprehensive cosmology remains possible. That knowledge represents something profound,
2:20:07
not just data about galaxy distributions or expansion rates, but
2:20:12
humanity's attempt to understand the largest structures and longest time
2:20:17
scales accessible to observation, to map reality at its most
2:20:23
fundamental scales, to document the universe. While documentation remains possible,
2:20:30
the terrifying void is already here, already growing, already separating
2:20:36
structures that will never reconnect. This process began billions of
2:20:41
years ago, will continue billions of years into the future,
2:20:46
where witnesses to a cosmic transformation from structure to emptiness,
2:20:52
from connection to isolation, from the middle chapter toward the
2:20:57
final state. The universe does doesn't care whether we find
2:21:01
this terrifying. It simply follows the physics. Dark energy does
2:21:06
what dark energy does. Space expands as equations predict voids
2:21:12
grow as mathematics demands. But we can choose how we respond.
2:21:17
We can observe, carefully, measure, precisely, record, thoroughly share knowledge
2:21:24
widely ensure that what we learn during this era survives
2:21:29
for whatever comes after. Because the voids are patient, they
2:21:34
have billions of years to complete their work, to stretch
2:21:38
space beyond all possible reconnection, to isolate every structure in
2:21:43
its own expanding bubble, to transform the cosmos from its
2:21:48
current complexity into final simplicity. We have perhaps one hundred
2:21:54
billion years before the observable universe shrinks to just our
2:21:59
local classies. That sounds generous until you realize its finite,
2:22:05
until you understand that after that window closes, certain knowledge
2:22:09
becomes permanently inaccessible. The cosmic web we photograph today will
2:22:15
exist only in records. The expansion we measure now will
2:22:20
have carried everything beyond observation. The universe we study will
2:22:26
have hidden itself behind horizons that cannot be crossed. This
2:22:30
is what makes the void truly terrifying, not its emptiness,
2:22:36
not even its relentless expansion, but the certainty that it
2:22:41
represents the future, the inevitability that all structure will eventually
2:22:47
dissolve into isolated fragments separated by unbridgable distances. The universe
2:22:54
began in near uniformity. Quantum fluctuations created slight variations. Gravity
2:23:01
amplified those variations into structure. The cosmic web emerged, galaxies formed,
2:23:07
stars ignited. Complexity arose from simplicity. Now dark energy is
2:23:13
reversing that process, not by destroying structures, but by separating them,
2:23:19
returning the universe to large scale uniformity. Except this time
2:23:25
the uniformity is one of emptiness rather than density. We're
2:23:30
living through the transition, observing the cosmic web before its fragments,
2:23:35
measuring void expansion while boundaries still exist, documenting structure while
2:23:42
structure remains visible. This makes our era special, not because
2:23:47
we're cosmically important, not because the universe treats us differently,
2:23:53
but because we happen to exist when observation remains comprehensive,
2:23:59
when in the universe's large scale structure stretches across our sky,
2:24:05
when we can still see what's being lost. The voids
2:24:09
are teaching us that impermanence is fundamental, that structure is temporary,
2:24:15
that separation is permanent, that the universe trends inexorably toward
2:24:21
maximum entropy, regardless of what we might prefer. They're showing
2:24:26
us our cosmic future, not through speculation, but through direct observation.
2:24:33
We can see what awaits all of space by looking
2:24:36
at voids today, empty regions where dark energy dominates, where
2:24:42
expansion proceeds unimpeded, where the universe's final state is already manifesting.
2:24:48
And perhaps most importantly, they're reminding us that knowledge itself
2:24:53
is temporary, that comprehensive understanding requires the right cosmic conditions,
2:25:01
that we're fortunate to live when those conditions exist, That
2:25:06
this window won't remain open forever. The void is already
2:25:11
swallowing the universe, not through destruction, but through separation, not violently,
2:25:18
but inexorably, not quickly, but certainly. The process has been
2:25:23
under way since dark energy began dominating. Cosmic evolution will
2:25:28
continue until every structure exists in isolated darkness, until the
2:25:33
cosmic web has completely dissolved, until voids occupy essentially all
2:25:39
of space. We cannot prevent this, cannot reverse it, cannot
2:25:44
escape it. All we can do is observe while observation
2:25:49
remains possible, understand while understanding remains accessible, Record while there's
2:25:55
still something to record. The terrifying void isn't coming. It's here,
2:26:02
growing steadily, claim in more space with each passing moment,
2:26:07
teaching us that everything we observe today is temporary, that
2:26:12
the cosmic web will dissolve, that isolation awaits all structures,
2:26:18
that emptiness is the universe's ultimate destiny. This is the
2:26:23
reality revealed by modern cosmology, measured through careful observation, confirmed
2:26:30
across multiple methods, projected forward through well established physics. The
2:26:37
universe is transforming from structure to void, from connection to separation,
2:26:44
from complexity to simplicity, and we're witnessing the transition while
2:26:49
we still can