Episode Transcript
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All right, picture this.
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You're an astronomer, and you're mapping the universe
like a cosmic cartographer.
You'd think you'd see galaxies spread out kind of evenly,
right?
I mean, that's what we've always been told.
The universe is pretty uniform, at least on a grand scale.
Yeah, that's the general idea.
But then bam, you find something totally unexpected,
like a massive empty space stretching for billions
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and billions of light years.
It'd be like finding a giant hole
in the fabric of the cosmos, and that's
exactly what happened when astronomers stumbled
upon the KBC void.
Talk about turning our understanding of the universe
upside down.
It really is a mind-boggling discovery.
I mean, it challenges some of our most fundamental assumptions
about how the universe is structured, how it works,
all of that.
Well, to Cosmos and a Pod, the Space and Astronomy series.
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Please like, comment, share, and subscribe.
Today, we're diving deep into the KBC void,
a cosmic enigma that's making us rethink everything.
We're talking the expansion of the universe,
even the existence of dark matter, all of that.
And maybe even our place in the grand scheme of things.
OK, so let's start with the basics.
How did we even find this void?
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It's not like there's a giant signpost out there
saying, welcome to the KBC void.
Yeah, no kidding.
Astronomers actually found it using a technique
called redshift surveys.
Basically, they measure the light
from really, really distant galaxies
and look for something called redshift.
As the universe expands, the light from those galaxies
gets stretched, and that shifts its wavelength
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towards the red end of the spectrum.
So the farther away a galaxy is, the more
its light is redshifted.
Exactly.
It's kind of like a cosmic Doppler effect.
Exactly.
And by measuring the redshift of a whole bunch of galaxies,
astronomers can create these incredible 3D
maps of the universe.
These maps show where galaxies are clustered together
and where they're sparse.
And in this case, the redshift surveys
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revealed this massive region with way fewer
galaxies than expected.
The KBC void.
Exactly.
And to give our listeners a sense of scale,
just how big are we talking here?
Well, the KBC void is a mind blowing 2 billion light
years across.
If you could travel at the speed of light, which you can't,
but if you could, it would still take you
2 billion years to cross it.
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Wow.
And to put that into perspective,
that's seven times larger than the average void predicted
by our standard cosmological models.
2 billion years of emptiness.
That just boggles the mind.
It makes you wonder what's going on in there,
or rather what's not going on in there.
That's the big question, isn't it?
And it challenges one of the key principles in cosmology,
the cosmological principle.
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This principle says that on a large scale,
the universe should look pretty much the same
from any point of observation.
Matter should be spread out more or less evenly.
But the KBC void is like this giant exception to the rule.
Exactly.
It's like finding a giant empty bubble in a sea of galaxies.
So this void is really challenging our understanding
of how the universe is structured.
But what about its behavior?
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How does the KBC void affect things
like the expansion of the universe?
I mean, we hear a lot about the Hubble tension,
this discrepancy between different measurements
of how fast the universe is expanding.
Could the void have something to do with that?
It's definitely a possibility, and scientists
are actively researching it.
Think of it like this.
Imagine you're on a moving walkway at the airport.
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If you're not paying attention, you
might think you're walking faster than you actually
are because the walkway is giving you a boost.
In a similar way, if we're inside this giant void,
the lack of matter and gravity inside the void
compared to the denser region surrounding it
could create a sort of cosmic headwind.
That could make it seem like the universe is expanding faster
in our local neighborhood.
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So our location being nestled inside this void
could be skewing our measurements of how
fast the universe is expanding.
It's a good analogy.
And that's why the KBC void is so important.
It could help us solve the Hubble tension
and get a more accurate understanding of how fast
the universe is really expanding.
OK, so the void might be messing with our measurements.
But what about the models we use to understand
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the universe in the first place?
Does the KBC void challenge those too?
Absolutely.
The most widely accepted model we have
is called the Lambda CDM model.
It includes things like dark matter and dark energy
to explain how the universe behaves.
Dark matter, that mysterious stuff we can't see,
but we know it's there because of its gravitational effects.
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And dark energy, the force that's
pushing the universe to expand faster and faster.
That's it.
The Lambda CDM model has been incredibly successful
at explaining a wide range of observations
we've made about the universe.
But here's the catch.
It doesn't easily explain voids as massive as the KBC void.
So our best model of the universe
doesn't quite know what to do with this giant hole in space.
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Does that mean we need to throw the whole model out
and start over?
Not necessarily.
But we definitely need to look closer
at the model's assumptions and see
if they need some tweaking.
Or maybe it's a sign that we should consider
alternative theories like modified Newtonian dynamics
or MOND.
MOND suggests that we might not need dark matter
to explain everything.
Maybe we just need to adjust our understanding
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of how gravity works.
MOND is that theory that says gravity acts differently
on really large scales.
Exactly.
Instead of needing dark matter, MOND
proposes that we just need to modify
the laws of gravity themselves.
Interesting.
So MOD might be better at explaining
how these massive voids like the KBC void formed.
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It's really amazing to think that something is seemingly
empty as a void could be so crucial to our understanding
of the universe.
It really is.
And this is just the beginning of our exploration
of the KBC void.
There's so much more to uncover.
So where do we go from here?
Well, next we can dive into what the KBC void might
mean for one of the biggest questions in science.
Are we alone in the universe?
Ah, the Fermi paradox.
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We see this vast ancient universe teaming
with stars and planets.
And yet we haven't found any definitive proof
of other civilizations.
Could the KBC void be a piece of that puzzle?
It just might.
But we'll explore that fascinating topic
after a quick break.
So before the break, we were talking
about how the KBC void might be connected
to the Fermi paradox, that whole puzzle of why
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we haven't found any aliens yet.
Right.
It's like you look up at the night sky
and see all those stars.
And you can't help but think somebody's
got to be out there somewhere.
Exactly.
So let's think about this in terms of the KBC void.
Imagine you're searching for life in a desert.
Where would you go?
Probably to an oasis, right?
Someplace with water and what life needs to survive.
Exactly.
Now apply that same logic to the universe.
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The KBC void with its lower density of galaxies and stars
is kind of like a vast cosmic desert.
So fewer stars means fewer planets.
And that means fewer chances for life to pop up.
Precisely.
The odds of intelligent life emerging
in our little corner of the void would be much lower compared
to denser, more happening parts of space.
So it's all about cosmic real estate.
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Like the void just isn't the best neighborhood for life
to get going.
That's one way to think about it.
But even if life did manage to arise somewhere else
in the void, the distances involved
would make contact or even just detecting them
incredibly difficult.
You're talking about those mind boggling distances we discussed
earlier, billions of light years just to cross the void.
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Exactly.
Imagine trying to send a message across that kind of gulf.
It would take billions of years for the signal to get there
and then billions more for a response.
Right.
By then, who knows if either civilization would even still
be around.
It'd be like tossing a message in a bottle.
But on a cosmic scale, the chances
of it reaching anyone, let alone them understanding it,
are pretty slim.
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Exactly.
So even if we aren't completely alone in the void,
we could be effectively isolated,
unable to communicate across those vast distances.
That we could be alone or we could just
be stuck in a cosmic communication black hole.
It's definitely a possibility.
But here's another intriguing thought.
What if advanced civilizations far beyond our tech level
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are actually avoiding voids like ours?
Avoiding them?
Why would they do that?
Seems kind of counterintuitive.
Think about it from their perspective.
They might see voids as areas that lack resources
and opportunities.
Imagine a civilization that's mastered interstellar travel
and energy manipulation.
Why bother with a sparsely populated void
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when you have access to the abundant resources of galaxy
clusters?
It's like choosing to live in a tiny village,
when you could be in a bustling city with everything you need.
Exactly.
So even if these super advanced civilizations are out there
exploring, they might just overlook voids
like the KBC void and focus on areas that have more to offer.
So not only could we be isolated within the void,
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but we might also be getting ignored by the cool kids
in the Galactic Club.
Talk about double dose of cosmic loneliness.
It's a bit of a bleak perspective, I'll admit.
But it could be a possible explanation
for why we haven't encountered any signs
of extraterrestrial life.
OK, so the KBC void might be contributing
to our cosmic isolation.
But I want to shift gears a bit and explore
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another interesting aspect of this void.
Earlier, we talked about how its existence challenges
our cosmological models, especially the Lambda CDM
model.
Right, the one that relies on dark matter and dark energy
to explain what we observe.
Exactly.
But what if the void's influence goes beyond just challenging
our models?
What if it actually tells us something profound
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about the very nature of the universe itself?
What if, and here's where it gets really interesting,
the KBC void is actually connected
to our very existence?
I see where you're going with this.
You're thinking about the anthropic principle,
the idea that the universe's properties are just
right for life.
Because if they weren't, we wouldn't be here to observe
them.
Exactly.
It's mind blowing to think that our existence as observers
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could be tied to the very structure of the universe,
including the presence of these massive voids
like the KBC void.
It is a really deep concept.
But how does the KBC void fit into the anthropic principle?
Well, think about the void's characteristics.
It's relatively calm, isolated from the more
chaotic and energetic parts of the universe.
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Could this environment, this cosmic tranquility,
have actually been crucial for life to emerge and evolve?
You're suggesting the void acts like a shield,
protecting us from the more dangerous parts of the universe.
Exactly.
Denser regions of space are more likely to have
supernovae gamma ray bursts and other high energy events that
could wipe out life.
But inside a void, those threats are minimized.
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It's like a cosmic safe zone.
It's an interesting idea.
The void, which at first glance seems empty and hostile,
could actually be the perfect cradle for life.
It's a complete flip from what we normally think right.
We can depict your life flourishing
in vibrant, busy environments.
But what if it's the quiet, seemingly desolate places that
hold the key to our existence?
It makes you wonder, could our location inside the KBC void
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be more than just chance?
Could it be a fundamental reason for our very being?
It's almost as if the universe created these vast voids
to be nurseries for life, protecting them
from the wilder parts of space.
It's a fascinating idea, and it adds another layer of mystery
to the KBC void.
Not only does it challenge our understanding
of how the universe is built and how it works,
but it might also be closely linked to our origins.
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So the void might be more than just a cosmic cradle.
It's also a window into the universe's past,
a record of how it's changed over billions of years.
Absolutely.
And to understand the void's story,
we need to dive into its dynamic nature, how
it's evolving over time, and what
that reveals about the forces shaping the cosmos.
So we were discussing how this massive void might actually
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be tied to our existence, maybe even acted
as a kind of cosmic cradle for life, pretty wild stuff.
Yeah, it really flips the script on where
we might expect to find life out there in the universe.
But you also mentioned that the KBC void gives us
a glimpse into the universe's past,
like a record of how it's changed over billions of years.
Exactly.
It's like, think of the universe as this huge, ever-expanding
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tapestry, the KBC void, with its unique properties
and its sheer size.
It's like we can zoom out and see the larger patterns woven
into that tapestry.
Patterns?
What kind of patterns are we talking about?
Well, one of the most amazing things about the KBC void
is that it's not alone.
It's part of this vast network of cosmic voids
that make up what we call the cosmic web.
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Cosmic web.
Sounds like something straight out of science fiction.
It's a pretty fitting name.
Picture this vast interconnected network of filaments
and clusters of galaxies with these giant voids
scattered throughout, almost like bubbles in cosmic foam.
So our void is just one bubble in a giant cosmic bubble bath.
That's a great way to put it.
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And what's even more fascinating
is that these voids aren't just randomly placed.
They seem to be arranged in a pattern,
almost like a honeycomb or a sponge.
A pattern.
That suggests there's some kind of underlying order
or structure to the universe, right?
It's not just random chaos.
Exactly.
And that's why the cosmic web is so intriguing.
It's like a giant cosmic fingerprint
that holds clues about the conditions and forces that
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shape the universe way back in its early stages,
right after the Big Bang.
So by studying these voids, how they're shaped,
how big they are, and how they're connected,
we can learn about the very beginning of the universe.
Exactly.
The cosmic web is like a fossil record of the early universe.
It gives us hints about what drove its expansion,
how galaxies formed, and how those cosmic structures
evolved over time.
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Wow.
It's mind blowing to think that something as seemingly empty
as a void could hold so much information
about the universe's past.
It really shows how interconnected everything
in the cosmos is.
Even the emptiest regions play a crucial role
in our understanding of the big picture.
And the KBC void being one of the largest voids we know of.
It's like a giant laboratory for studying
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these cosmic patterns and processes.
Absolutely.
And as we develop even more powerful telescopes
and better ways of observing the universe,
we'll be able to explore the KBC void and the cosmic web
in even greater detail, unlocking more secrets
about how the universe evolved and what it's made of.
It's amazing to think that we're only just starting
to understand something as vast and complex as the KBC void.
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It really puts things in perspective.
It makes you realize that every discovery,
every little bit of knowledge we gain,
is just a tiny step on this never-ending journey
of exploring the cosmos.
It's a journey filled with wonder mystery and endless
possibilities for discovery.
It truly is.
Well, on that note of cosmic wonder
and the thrill of the unknown, I think
it's time to wrap up our deep dive into the KBC void.
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It's been a fascinating exploration.
Absolutely.
Thanks to everyone for joining us on this cosmic adventure.
We hope you've enjoyed learning about this mind-boggling
structure and what it means for our understanding
of the universe.
And if you're as intrigued by the KBC void as we are,
we encourage you to keep exploring and learning.
There's a ton of information available online in libraries
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and at science museums.
And of course, don't forget to follow and subscribe
to Cosmos Cinepod on your favorite podcast app.
And check out our YouTube channel
for even more awesome content about space and astronomy.
We're always exploring new cosmic frontiers
and sharing the wonders of the universe with all of you.
Until next time, keep looking up and stay curious.
The universe is full of surprises,
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just waiting to be discovered.
And who knows, maybe one of you listening right now
will be the one to make the next big breakthrough
in our understanding of the KBC void
and all the mysteries it holds.