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Supermassive black holes,

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the engines that power
our universe.

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Supermassive black holes are
one of the major players

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in the evolution of galaxies.

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With no supermassive
black holes,

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you have no Milky Way Galaxy,
no sun, no Earth, no you.

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They're the driving force
at the heart

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of nearly every galaxy
in the cosmos.

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They are the most monstrous and
scary and bizarre aspects of

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our world,
which just fascinates me.

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Now, a new mystery has emerged

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about the oldest supermassive
black holes.

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We see supermassive
black holes in

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the very early universe.

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And we don't understand how
they grew so large so quickly.

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We have clues about
their formation.

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But can we solve the mystery

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of this supermassive
growth spurt?

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2017.

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Scientists gazing deep into

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the distant universe
discover something

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completely unexpected...

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A vast supermassive black
hole dating

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from the earliest days
of the universe.

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This was 690 million
years after the Big Bang.

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The universe was about 5 or
6% of the age that it is now.

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Finding a supermassive black
hole in the early universe is

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like finding an NFL
defensive lineman playing

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in peewee football.

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Something that big shouldn't
exist that young.

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The supermassive black
hole wasn't just super early.

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It was super big, 800 million
times the mass of our sun.

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In just a few hundred
million years,

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the universe has somehow been
able to collapse nearly

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a billion suns' worth of

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material into
a giant black hole.

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And we honestly just don't
know how that's possible.

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We measure black holes
by the mass of our sun...

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Solar masses.

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Regular, or stellar,
black holes are a few

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to a hundred solar masses.

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Supermassive black holes weigh
from 100,000 to billions

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of suns.

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And scientists have now found
over 100 of these monsters in

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the early universe.

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We were shocked to find even one
of them existing so early

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after the Big Bang.

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It was kind of freakish,
to be honest,

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but then to find that there's
whole populations

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of these things that exist
and are well

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in place at the earliest times

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that we can look at
was truly shocking.

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We believe
supermassive black holes might

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help explain the evolution
and the destiny of the universe.

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Astronomers are striving
to understand them.

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Understanding the origin

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of supermassive black holes
and how

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they could form so early
in the universe's history is

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something that would change all
of astronomy and astrophysics.

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How do you get something
that massive to

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form in such a short amount
of time?

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It's a big question...
To begin to answer it,

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we have to start small,
by asking

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how regular stellar
black holes form.

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Black holes form
through the collapse of stars.

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Everyone knows that...
You have a big enough star,

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and it'll collapse to
form a black hole.

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A really massive star dies in
a violent supernova explosion,

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and if they have sufficient
mass, what's left over

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collapses into a black hole.

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The bigger the star was,

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the bigger the black hole
is to start with.

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Were the stars
of the early universe

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big enough to collapse into
supermassive black holes?

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The very early universe was
much different than

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the university you see
around us today.

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It was filled entirely with
hydrogen and helium gas.

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This gas amassed
into giant clouds,

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which collapsed
under their own gravity.

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Nuclear fusion ignited
the dense cores,

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and the first stars were born.

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Now, we think that these
earliest clouds of gas probably

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made bigger stars than clouds

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of gas do in our local
or today's universe.

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It was possible to get huge,
giant stars that we call

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Population III stars that
were just utterly massive.

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Population III stars are
the oldest category of star.

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Like stellar dinosaurs,

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they dominated the universe
a long time ago.

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Now, they're extinct.

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They'd be weird stars.

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They would be incredibly
bright in the ultraviolet

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and have very unique signatures

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that are very different
from stars today,

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but precisely because they're
so big and so bright,

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they would be very short-lived.

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These first stars
lived fast and died young...

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...exploding in supernovas,
leaving behind black holes.

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But were they supermassive
black holes?

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When a star blows up,
when it goes supernova,

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most of the mass
is ejected away.

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It just goes flying out,

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leaving a dense neutron star
or perhaps a black hole.

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But it won't have much
mass, because

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most of that mass was
blown away.

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Even though Population III
stars in the infant universe

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were very large,

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they weren't big enough to
leave a supermassive black hole

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behind when they exploded.

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Perhaps if we can skip
the supernova step,

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that might be one pathway to
understanding how supermassive

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black holes formed.

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Could a dying star's entire
mass collapse

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into a black hole?

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A clue may lie in a galaxy
nicknamed the Fireworks Galaxy.

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The Fireworks Galaxy has that

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flashy name,
because when you look at it,

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there are all these supernova
explosions going off

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and, um, making quite a show.

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Recently, astronomers
were keeping an eye on

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one extremely bright star
in the Fireworks Galaxy.

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This star is exactly the kind

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that we know explodes
as a supernova.

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Astronomers expected it
to explode,

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but then it did something
even weirder.

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Astronomy is so wonderful,
because sometimes you see things

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right in front of your eyes
that you can't explain.

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We saw an entire star
just disappear.

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In 2007, the star
looked like this.

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By 2015, it had
completely vanished.

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There was no flare

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or debris
from a supernova explosion.

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So what the heck is going on?

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It turns out that not
every massive star blows up

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with all the fireworks
of a normal supernova.

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You can get what's called
a failed supernova.

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A supernova fails
when the shockwave

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generated inside a collapsing
star can't escape.

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In some cases,
when the star is very massive,

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the shockwave never has a chance
to get all the way out of

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the star by the time
the star itself

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collapses into a black hole,

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then you have
a failed supernova.

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The Fireworks Galaxy star
may have been massive enough to

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smother its own explosion
before collapsing

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to form a black hole.

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Everything collapses
into the black hole.

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You can actually
have a black hole

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with all the mass of
the original star.

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Back in the early universe,

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could the enormous
Population III stars have died

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as failed supernovas,

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leaving behind supermassive
black holes?

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These Population III stars
don't seem to me to be

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a good contender for
the precursor to supermassive

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black holes... they just
would not have enough mass.

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Even
the most massive stars are only

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a couple of hundred times
more massive than our sun,

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whereas a supermassive black
hole is millions or billions of

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times the mass of our sun.

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Early supermassive black holes

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can't have formed
from collapsing stars.

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Even giant stars aren't
massive enough.

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So is there some other path to
being supermassive?

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Were stellar black holes

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cosmic bodybuilders on
a fast-track bulking program?

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How did
supermassive black holes in

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the early universe get
so large so quickly?

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We ruled out the idea
that they were

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created from the collapse of
very large stars.

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Maybe they started out
as smaller,

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stellar mass black holes
and grew to be supermassive

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by eating.

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Black holes
are not fussy eaters.

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They'll consume anything that
comes in their path.

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You know, gas, planets, stars.

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It doesn't matter,
and everything that they

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consume adds mass
to the black hole.

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We've spotted
a stellar mass black hole

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currently eating
in our Milky Way Galaxy.

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15 times the mass of the sun,

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Cygnus X-1 is steadily feeding

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off the material
that swirls around it.

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Some black holes are
fed through things called

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accretion disks.

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It's kind of like the rings
around Saturn.

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There's this thick
or thin disk of

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material around the black hole
that feeds it.

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Cygnus X-1's secretion disc gets

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constant refills
from a nearby source,

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a vast star 20 times the mass

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of the sun called
a blue supergiant.

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The black hole has been
feeding on gas

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from this star for about
five million years.

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So if you ask, how do
black holes eat or consume gas?

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The answer is gravity, these are

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very massive objects, and
anything that comes within

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their sphere of influence can
be consumed by the black hole.

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The more mass
a black hole gains, the greater

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its gravity and the more food
it attracts.

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A black hole growing
is a little bit

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like a snowball rolling
down a hill.

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The bigger the snowball gets,
the more snow it

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can accumulate,
and so the bigger it gets.

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It's a runaway effect.

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But even if Cygnus X-1
follows this runaway

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growth trajectory,

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it still may never reach
supermassive status.

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The black holes of
the early universe must

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have fed at a much faster rate.

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The biggest issue
is how do you have

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enough time in the early
universe to go

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from a small black hole
that's born from a star to

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something that's supermassive?

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GRS 1915 is another
stellar mass black hole.

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It's a greedy eater,
accreting at up to

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40 times the rate of Cygnus X-1,

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and when something gobbles
food that quickly,

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it can begin to overheat.

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The black hole is
accreting a lot of material,

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and as it's eating,

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the accretion disc
really heats up to very

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high temperatures.

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And at those high temperatures,
you can get

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a lot of light
coming out of the system.

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So the more material that
a black hole eats and swallows,

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the brighter it shines.

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This stellar black hole
sometimes eats so much

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so quickly, its accretion disk

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pushes out radiation
almost a million times brighter

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than our sun,

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but this brightness has
a serious consequence.

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It stops the black hole from
eating and growing larger.

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If you wanted me to gain
as much mass as possible as

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quickly as possible,
you would just keep

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feeding me hamburgers nonstop
or whatever, but...

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black holes have a problem
that when they eat a lot,

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they tend to just gobble up
a lot of the food in

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the neighborhood, and then also,

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they start shining out
so much stuff

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that it pushes away much
of the food.

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The brightness, or luminosity,

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gets so intense, it pushes away

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incoming material,

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a sort of safety valve called
the Eddington Limit.

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So in many ways,
the Eddington rate could be

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a kind of a speed limit for
the growth of black holes.

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It could be a governor that
prevents black holes from

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growing even faster

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by just dumping more and more
gas onto it.

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Eventually, you're gonna hit
that Eddington limit,

252
00:13:23,536 --> 00:13:25,003
and that more gas

253
00:13:25,104 --> 00:13:27,705
that you're dumping on won't
actually reach the black hole.

254
00:13:28,974 --> 00:13:31,176
This cosmic method
of portion control

255
00:13:31,277 --> 00:13:33,044
means that
stellar black holes in

256
00:13:33,145 --> 00:13:37,081
the early universe couldn't
have gained weight fast enough

257
00:13:37,183 --> 00:13:40,485
to become supermassive.

258
00:13:40,586 --> 00:13:42,787
Black holes need time to grow.

259
00:13:42,888 --> 00:13:44,789
They need to feed.
They need to eat.

260
00:13:44,890 --> 00:13:47,025
Maybe you need
to skip a few steps.

261
00:13:47,126 --> 00:13:51,396
Maybe you need to start at
a medium size or bigger

262
00:13:51,497 --> 00:13:55,066
in order to get to supermassive
by the time we observe it.

263
00:13:56,435 --> 00:13:58,803
So was there another
type of black hole

264
00:13:58,904 --> 00:14:00,104
in the early universe?

265
00:14:00,206 --> 00:14:03,575
Something big enough
to grow supermassive

266
00:14:03,676 --> 00:14:04,776
in the time available?

267
00:14:09,415 --> 00:14:12,283
In 2017, astronomers studied

268
00:14:12,384 --> 00:14:14,485
a dense star cluster called

269
00:14:14,587 --> 00:14:19,023
47 Tucanae on the outskirts
of our own galaxy.

270
00:14:20,559 --> 00:14:23,228
They detected 25 pulsars,

271
00:14:23,329 --> 00:14:25,930
bodies that spin
and emit radiation

272
00:14:26,031 --> 00:14:27,732
like cosmic lighthouses.

273
00:14:29,068 --> 00:14:33,805
These pulsars are all
orbiting a central object.

274
00:14:33,906 --> 00:14:36,507
And even though we couldn't
see the central object itself,

275
00:14:36,609 --> 00:14:41,012
we could watch the behavior in
the orbits of all these pulsars

276
00:14:41,080 --> 00:14:43,281
around it,
and we could figure out

277
00:14:43,382 --> 00:14:46,017
how big that central object was.

278
00:14:46,118 --> 00:14:47,452
Well, when you do the math,

279
00:14:47,553 --> 00:14:51,189
you come up with something
that is about 1,500 to 2,000

280
00:14:51,290 --> 00:14:53,524
times the mass of the sun
that's actually hidden in

281
00:14:53,626 --> 00:14:55,059
the heart of that
globular cluster.

282
00:14:55,160 --> 00:14:58,029
So what is the invisible object?

283
00:14:58,130 --> 00:15:03,167
Whatever's lurking at
the center of 47 Tucanae has

284
00:15:03,269 --> 00:15:06,704
to be big,
and it has to be black.

285
00:15:06,805 --> 00:15:09,807
Astronomers think
it's a large black hole.

286
00:15:09,909 --> 00:15:12,110
At 1,500 times

287
00:15:12,211 --> 00:15:14,279
the mass of the sun, the object

288
00:15:14,380 --> 00:15:17,715
is much bigger than a regular
stellar black hole,

289
00:15:17,816 --> 00:15:21,152
but too small to
be supermassive.

290
00:15:21,253 --> 00:15:25,623
Could it be what's known as
an intermediate mass black hole?

291
00:15:25,724 --> 00:15:28,893
It's extremely hard to find any

292
00:15:28,994 --> 00:15:32,196
of these intermediate
mass black holes.

293
00:15:32,298 --> 00:15:34,666
This rare category of black hole

294
00:15:34,767 --> 00:15:38,870
ranges between 100
and 100,000 solar masses.

295
00:15:38,971 --> 00:15:41,205
At that size, they may have

296
00:15:41,307 --> 00:15:45,143
been large enough to become
supermassive very quickly.

297
00:15:45,244 --> 00:15:48,947
Intermediate mass black holes
could be what give

298
00:15:49,048 --> 00:15:52,684
supermassive black holes
a head start in life.

299
00:15:52,785 --> 00:15:54,819
Astronomers have never seen

300
00:15:54,920 --> 00:15:56,955
an intermediate mass black hole,

301
00:15:57,056 --> 00:16:01,192
but now, we've heard one,
calling to us

302
00:16:01,293 --> 00:16:02,860
from across the universe.

303
00:16:15,607 --> 00:16:19,610
Astronomers search for
intermediate mass black holes.

304
00:16:19,712 --> 00:16:21,112
They may have been large enough

305
00:16:21,213 --> 00:16:24,115
to act as seeds
for the first supermassive

306
00:16:24,216 --> 00:16:25,817
black holes.

307
00:16:25,918 --> 00:16:28,820
Yet so far,
they've escaped discovery.

308
00:16:28,921 --> 00:16:30,855
They're like
the missing link. And I

309
00:16:30,956 --> 00:16:33,024
mean that for real.
They're missing.

310
00:16:33,125 --> 00:16:36,127
Imagine you're an alien who's
arrived on the planet Earth,

311
00:16:36,228 --> 00:16:39,097
and you know very little
about the human species,

312
00:16:39,198 --> 00:16:42,033
and when you look around,
you only notice tiny,

313
00:16:42,134 --> 00:16:44,402
tiny little children
and grown adults.

314
00:16:44,503 --> 00:16:47,171
You don't see any
adolescents, right?

315
00:16:47,272 --> 00:16:49,807
And intrinsically, you know
that the tiny little

316
00:16:49,908 --> 00:16:53,044
children grow up to be
full-size adults.

317
00:16:53,145 --> 00:16:55,813
But you don't see how
they got there, right?

318
00:16:55,914 --> 00:16:58,182
You don't see the intermediate
stages of growth.

319
00:16:58,283 --> 00:17:00,451
That would be really,
really weird, right?

320
00:17:00,552 --> 00:17:03,221
That is the case for
supermassive black holes.

321
00:17:03,322 --> 00:17:06,457
So it's like a universe
without teenagers.

322
00:17:06,558 --> 00:17:10,094
Or that's how it looked,
until September 2020.

323
00:17:10,195 --> 00:17:13,531
Scientists studying
gravitational waves

324
00:17:13,632 --> 00:17:16,434
picked up the signal of
an extreme event

325
00:17:16,502 --> 00:17:18,403
in the distant universe.

326
00:17:18,504 --> 00:17:20,571
What researchers are looking for

327
00:17:20,672 --> 00:17:22,807
are things called
gravitational waves.

328
00:17:22,908 --> 00:17:25,710
They're like ripples
in space itself.

329
00:17:25,811 --> 00:17:29,213
Most signals sound
a little bit like a chirp.

330
00:17:29,314 --> 00:17:31,816
It's a noise that's
very characteristic.

331
00:17:31,917 --> 00:17:33,418
It goes a bit, like,
sort of whoop!

332
00:17:35,721 --> 00:17:38,689
But this particular event
was so extreme

333
00:17:38,791 --> 00:17:41,459
and so sudden, it just sounded
more like a thud.

334
00:17:43,595 --> 00:17:46,597
This faint thud
from halfway across the universe

335
00:17:46,698 --> 00:17:51,002
is music to the ears of
intermediate black hole hunters,

336
00:17:51,103 --> 00:17:53,971
because its pitch
can mean only one thing.

337
00:17:54,073 --> 00:17:57,875
This could only have been
created by two

338
00:17:57,976 --> 00:18:02,246
really massive black holes
colliding into each other

339
00:18:02,347 --> 00:18:04,982
and producing
a combined black hole with

340
00:18:05,084 --> 00:18:10,955
a mass that's 142 times
the mass of our sun.

341
00:18:11,056 --> 00:18:13,624
So that, is for the first time,

342
00:18:13,759 --> 00:18:17,628
getting into this intermediate
mass black hole regime.

343
00:18:17,729 --> 00:18:20,198
This is the first confirmed

344
00:18:20,299 --> 00:18:23,468
observation of
an intermediate black hole.

345
00:18:23,569 --> 00:18:26,037
Finding direct evidence
like this for

346
00:18:26,105 --> 00:18:30,041
an intermediate mass black
hole is absolutely fantastic.

347
00:18:31,410 --> 00:18:34,479
Now that we're certain
intermediate black holes exist,

348
00:18:34,580 --> 00:18:37,348
could they help explain
the origin of supermassive

349
00:18:37,449 --> 00:18:39,183
black holes
in the early universe?

350
00:18:39,284 --> 00:18:43,621
These intermediate black holes
really could be

351
00:18:43,722 --> 00:18:46,591
the first seeds of
the supermassive black holes.

352
00:18:46,692 --> 00:18:50,394
You would need something like
that to form really big,

353
00:18:50,496 --> 00:18:54,031
really early to even begin to
explain these very massive,

354
00:18:54,133 --> 00:18:56,367
supermassive black holes
that have formed

355
00:18:56,468 --> 00:18:59,170
just a short time
after the Big Bang.

356
00:18:59,271 --> 00:19:04,142
How do intermediate black
holes form in the first place?

357
00:19:04,243 --> 00:19:06,544
The recently discovered one
came from

358
00:19:06,645 --> 00:19:09,347
the collision of
two smaller black holes.

359
00:19:09,448 --> 00:19:13,317
They may also form
in giant clouds of gas.

360
00:19:13,418 --> 00:19:17,088
It could be that in
the earlier universe,

361
00:19:17,189 --> 00:19:21,192
you can just have large
clouds of gas that can lose

362
00:19:21,293 --> 00:19:23,427
enough energy quickly enough to

363
00:19:23,529 --> 00:19:28,666
just spontaneously collapse and
form a black hole of this size.

364
00:19:28,767 --> 00:19:32,236
The enormous cloud of
gas contracts and gets denser

365
00:19:32,337 --> 00:19:35,840
and denser, the way it would if
it was starting to form stars.

366
00:19:35,941 --> 00:19:38,376
But it's somehow able to
remain coherent

367
00:19:38,477 --> 00:19:40,811
and collapse
into one giant object

368
00:19:40,913 --> 00:19:43,147
that forms an intermediate
mass black hole.

369
00:19:44,616 --> 00:19:48,219
A giant gas cloud
undergoing a direct collapse

370
00:19:48,320 --> 00:19:50,922
down to
an intermediate mass black hole

371
00:19:51,023 --> 00:19:52,557
would be a rare sight.

372
00:19:55,994 --> 00:19:59,597
You think it would go giant
cloud, slowly collapsing,

373
00:19:59,698 --> 00:20:01,465
black hole, but instead,

374
00:20:01,567 --> 00:20:05,102
it's more like, giant cloud,
ahhhh!!!! Black hole.

375
00:20:06,171 --> 00:20:11,409
So one day, you see this
massive gas complex, and then

376
00:20:11,510 --> 00:20:13,611
you blink, and it's collapsed,

377
00:20:13,712 --> 00:20:17,181
and now you're face-to-face
with a big black hole.

378
00:20:17,282 --> 00:20:18,916
At least, that's the theory.

379
00:20:20,485 --> 00:20:22,687
Getting a black hole
to form from

380
00:20:22,788 --> 00:20:26,691
the direct collapse of
a gas cloud is very tricky.

381
00:20:26,792 --> 00:20:30,161
Gas clouds tend
to split up and collapse

382
00:20:30,262 --> 00:20:33,464
into a multitude of stars...
Collapsing into

383
00:20:33,565 --> 00:20:36,667
one object would take
unique conditions.

384
00:20:37,936 --> 00:20:42,640
One possible scenario involves
two neighboring galaxies.

385
00:20:42,741 --> 00:20:45,843
The first, a young protogalaxy,

386
00:20:45,944 --> 00:20:49,247
a gas cloud yet to form stars.

387
00:20:49,314 --> 00:20:53,417
Next door sits a larger galaxy.

388
00:20:53,552 --> 00:20:55,753
It's forming so many stars,

389
00:20:55,854 --> 00:20:58,990
radiation is bursting out
all over its young neighbor.

390
00:21:00,058 --> 00:21:02,026
Because they're in
close proximity,

391
00:21:02,127 --> 00:21:04,528
the energy from the large galaxy

392
00:21:04,630 --> 00:21:08,132
prevents the smaller galaxy
from forming its stars,

393
00:21:08,233 --> 00:21:10,201
so that means that
it will continue

394
00:21:10,302 --> 00:21:13,871
to collapse in cloud form
before moving to

395
00:21:13,972 --> 00:21:15,873
star formation.

396
00:21:15,974 --> 00:21:18,509
The gas cloud becomes
large and dense enough,

397
00:21:18,610 --> 00:21:21,512
the gravity eventually pulls
it in on itself.

398
00:21:22,881 --> 00:21:24,682
When it can't ignite into stars,

399
00:21:24,783 --> 00:21:28,019
the collapse creates
an intermediate mass black hole.

400
00:21:30,088 --> 00:21:32,790
I think this idea is
very intriguing.

401
00:21:32,891 --> 00:21:35,559
I don't know if it's
physically possible,

402
00:21:35,661 --> 00:21:36,761
but then again,

403
00:21:36,862 --> 00:21:39,063
there's a lot we don't know
about the early universe.

404
00:21:39,164 --> 00:21:44,068
Whichever way intermediate
mass black holes form,

405
00:21:44,169 --> 00:21:47,571
they seem like a good way to
start explaining supermassive

406
00:21:47,673 --> 00:21:50,741
black holes
in the early universe.

407
00:21:50,842 --> 00:21:52,910
The question is, then,
how do they grow?

408
00:21:53,011 --> 00:21:55,680
How do you start
from this seed and end up,

409
00:21:55,781 --> 00:21:57,992
you know, with something that's
a billion times the mass of

410
00:21:58,016 --> 00:21:59,250
the sun?

411
00:21:59,351 --> 00:22:03,020
Maybe early intermediate
mass black holes had

412
00:22:03,121 --> 00:22:04,555
enormous appetites,

413
00:22:04,656 --> 00:22:09,460
gorging themselves to
a supermassive state, feeding on

414
00:22:09,561 --> 00:22:13,431
the biggest meals
our universe can serve up.

415
00:22:26,278 --> 00:22:28,746
Astronomers want
to know how the earliest

416
00:22:28,847 --> 00:22:32,316
supermassive black holes got
so big so quickly.

417
00:22:35,487 --> 00:22:37,555
Could they have started
as intermediate

418
00:22:37,656 --> 00:22:41,492
mass black holes that devoured
supersized meals?

419
00:22:42,861 --> 00:22:45,930
It's possible that these
intermediate mass black holes

420
00:22:46,031 --> 00:22:49,266
could form in an exceptionally
rare environment where it can

421
00:22:49,368 --> 00:22:52,670
accrete new material
at an enormously high rate.

422
00:22:54,539 --> 00:22:56,207
So far, we only have direct

423
00:22:56,308 --> 00:23:00,144
evidence of one intermediate
mass black hole,

424
00:23:00,245 --> 00:23:04,415
and we can't yet detect
how it eats and grows.

425
00:23:04,516 --> 00:23:08,352
But we could look at much
larger black holes for clues.

426
00:23:09,688 --> 00:23:13,391
In 2019, astronomers searched
for supermassive

427
00:23:13,492 --> 00:23:16,594
black holes that are
actively feeding.

428
00:23:16,695 --> 00:23:18,763
They pinpointed 12 quasars

429
00:23:18,864 --> 00:23:21,432
from the beginning of
the cosmos.

430
00:23:21,533 --> 00:23:23,467
Quasars are among
the brightest objects

431
00:23:23,568 --> 00:23:24,902
we know of in the universe.

432
00:23:25,003 --> 00:23:28,339
And they're what happens when
a supermassive black hole at

433
00:23:28,440 --> 00:23:30,741
the center of a galaxy
is swallowing

434
00:23:30,842 --> 00:23:34,078
up gas and dust, and that
generates a tremendous amount

435
00:23:34,179 --> 00:23:37,181
of energy and luminosity
that we can see.

436
00:23:37,282 --> 00:23:39,483
Surrounding
these early galaxies are

437
00:23:39,584 --> 00:23:43,254
enormous gas reservoirs called
hydrogen halos.

438
00:23:43,355 --> 00:23:45,189
This is great, because that acts

439
00:23:45,290 --> 00:23:48,292
as fuel for those supermassive
black holes.

440
00:23:48,393 --> 00:23:51,729
Cold gas can stream into those
black holes and feed them.

441
00:23:51,830 --> 00:23:54,432
These huge halos of cold gas

442
00:23:54,533 --> 00:23:58,335
are also the building blocks
of stars.

443
00:23:58,437 --> 00:24:00,638
These enormous, pristine halos

444
00:24:00,739 --> 00:24:02,940
of hydrogen around
early galaxies,

445
00:24:03,041 --> 00:24:08,112
they're gonna be reservoirs
to power star formation.

446
00:24:08,213 --> 00:24:10,948
Star formation
is a violent process

447
00:24:11,049 --> 00:24:13,584
that can create turbulence
in a galaxy.

448
00:24:13,685 --> 00:24:17,822
That turbulence makes the gas
fall toward the black hole,

449
00:24:17,923 --> 00:24:21,325
and then that makes
the black hole even bigger.

450
00:24:21,426 --> 00:24:24,595
Hydrogen halos
might have spoon fed

451
00:24:24,696 --> 00:24:26,697
early supermassive black holes.

452
00:24:26,798 --> 00:24:29,967
This process may have
also helped

453
00:24:30,068 --> 00:24:33,370
intermediate mass black holes
grow quickly.

454
00:24:33,472 --> 00:24:37,074
Could the largest
black holes show us

455
00:24:37,175 --> 00:24:39,777
other, more drastic ways
to put on weight?

456
00:24:43,181 --> 00:24:47,117
In October 2019,
astronomers used telescopes to

457
00:24:47,219 --> 00:24:52,456
explore a remarkably clear
galaxy called M77.

458
00:24:52,557 --> 00:24:55,326
Because this galaxy
is so near to us,

459
00:24:55,427 --> 00:24:59,196
we can study its central engine
in really exquisite detail at

460
00:24:59,297 --> 00:25:01,632
very, very fine resolution.

461
00:25:01,733 --> 00:25:02,967
Not only do you see

462
00:25:03,068 --> 00:25:04,869
the bright core,
the bright nucleus,

463
00:25:04,970 --> 00:25:07,171
but you can see spiral arms.

464
00:25:07,272 --> 00:25:09,507
You can see structures
in the galaxy.

465
00:25:09,608 --> 00:25:13,611
You can see how the whole
galaxy is arranged.

466
00:25:13,712 --> 00:25:16,146
When we examined M77's central

467
00:25:16,248 --> 00:25:20,050
supermassive black hole,
we saw something extraordinary.

468
00:25:20,151 --> 00:25:23,087
Its food was coming
not from one,

469
00:25:23,188 --> 00:25:26,957
but two accretion disks
spinning in

470
00:25:27,058 --> 00:25:28,893
opposite directions.

471
00:25:28,994 --> 00:25:31,428
Normally around a black hole,
all of the gas is spinning in

472
00:25:31,530 --> 00:25:32,540
roughly the same direction,

473
00:25:32,564 --> 00:25:34,965
and that creates kind of
a slow infall of gas

474
00:25:35,066 --> 00:25:36,734
and slow feeding... here,

475
00:25:36,835 --> 00:25:38,246
we've got a case where
some of it's going

476
00:25:38,270 --> 00:25:41,038
one way, the other is going
the other way.

477
00:25:41,139 --> 00:25:44,308
This is very unstable and can
create opportunities for lots

478
00:25:44,442 --> 00:25:47,978
of gas to get gobbled up
by that black hole.

479
00:25:48,079 --> 00:25:50,214
The material in the disks

480
00:25:50,315 --> 00:25:54,385
is one enormous
ready-to-eat meal,

481
00:25:54,486 --> 00:25:57,521
but dinner will not be served
until the outer disk

482
00:25:57,622 --> 00:25:58,789
slows down.

483
00:25:58,890 --> 00:26:01,202
If there's a black hole
at the center of a galaxy,

484
00:26:01,226 --> 00:26:02,927
and you're orbiting around it

485
00:26:03,028 --> 00:26:05,162
fast enough to maintain
your orbit,

486
00:26:05,263 --> 00:26:06,897
you're never going to fall in.

487
00:26:06,998 --> 00:26:09,567
You're just going to orbit
forever, and you're just going

488
00:26:09,668 --> 00:26:11,078
to spin around,
just like the way the Earth

489
00:26:11,102 --> 00:26:12,403
is going around the sun.

490
00:26:12,504 --> 00:26:14,805
What needs to happen
if you wanna fall in,

491
00:26:14,906 --> 00:26:17,408
is to slow down your speed.

492
00:26:17,509 --> 00:26:20,411
The outer accretion disk
will gradually slow down

493
00:26:20,512 --> 00:26:23,213
and orbit more tightly against
the inner disk.

494
00:26:23,315 --> 00:26:26,984
Dangerous collisions of
the counter-rotating

495
00:26:27,085 --> 00:26:29,620
material will start to occur.

496
00:26:29,721 --> 00:26:32,256
The double accretion
disk is like drinking

497
00:26:32,357 --> 00:26:34,825
from two soda fountains at
the same time.

498
00:26:34,926 --> 00:26:36,226
It's great while it lasts,

499
00:26:36,328 --> 00:26:39,296
but you're building up some
serious gas that is just gonna

500
00:26:39,397 --> 00:26:41,131
blow the whole thing away.

501
00:26:41,232 --> 00:26:43,067
In just a few 100,000 years,

502
00:26:43,168 --> 00:26:46,270
the double disks will
catastrophically collide,

503
00:26:46,371 --> 00:26:49,006
and their entire contents
will fall

504
00:26:49,107 --> 00:26:52,676
into the central
supermassive black hole.

505
00:26:52,777 --> 00:26:55,512
It will devour everything
in one gulp,

506
00:26:55,614 --> 00:26:58,882
generating a colossal
cosmic burp.

507
00:27:06,424 --> 00:27:10,828
In February of 2020,
in the Ophiuchus Galaxy Cluster,

508
00:27:10,929 --> 00:27:14,164
we saw the damage
a cosmic burp can do.

509
00:27:16,301 --> 00:27:19,236
The Ophiuchus Galaxy
Cluster is a collection of

510
00:27:19,337 --> 00:27:22,573
a huge number of galaxies,
all bound together by gravity.

511
00:27:22,674 --> 00:27:25,576
And there's gas in between
these galaxies.

512
00:27:25,677 --> 00:27:27,745
And when astronomers
looked at that gas in detail,

513
00:27:27,846 --> 00:27:31,148
what they found was a huge
arcing structure in it that

514
00:27:31,249 --> 00:27:34,018
they realized was
the edge of a cavity.

515
00:27:37,322 --> 00:27:40,891
There is a massive hole
in the gas that is

516
00:27:40,992 --> 00:27:45,596
over 15 times bigger than
the entire Milky Way Galaxy.

517
00:27:45,697 --> 00:27:52,269
Something frightening had to
happen to carve this void out.

518
00:27:52,370 --> 00:27:56,740
The size of this bubble
is kind of stomping my brain.

519
00:27:56,841 --> 00:27:58,142
We are talking about

520
00:27:58,243 --> 00:28:03,747
a hole in this gas that is over
a million light-years wide.

521
00:28:03,848 --> 00:28:05,582
The burp that created
this cavity

522
00:28:05,684 --> 00:28:08,585
must have been
astoundingly powerful.

523
00:28:08,687 --> 00:28:10,821
There are a lot
of ideas about this,

524
00:28:10,922 --> 00:28:13,390
but there's only one that
really can explain it.

525
00:28:13,491 --> 00:28:15,259
And that's
a supermassive black hole.

526
00:28:16,728 --> 00:28:20,764
A supermassive black hole
that suddenly got very greedy.

527
00:28:21,833 --> 00:28:25,703
In order to drive an energetic
event like this,

528
00:28:25,804 --> 00:28:29,239
the black hole needs to eat...
Not just one meal.

529
00:28:29,340 --> 00:28:34,411
It needs to eat thousands of
meals at the exact same time.

530
00:28:34,512 --> 00:28:37,514
It needs to go
to an all-you-can-eat

531
00:28:37,615 --> 00:28:39,616
intergalactic buffet.

532
00:28:39,718 --> 00:28:41,652
Sometime in the distant past,

533
00:28:41,753 --> 00:28:46,957
this black hole must have had
a huge episode of just gorging

534
00:28:47,058 --> 00:28:50,094
on material falling in...
That got superhot,

535
00:28:50,195 --> 00:28:53,664
blew out a tremendous
amount of material in jets,

536
00:28:53,765 --> 00:28:56,767
beams that shot out
from the poles of the disk.

537
00:28:56,868 --> 00:29:00,637
And that's what basically
pushed its way out of that gas,

538
00:29:00,739 --> 00:29:03,140
forming this enormous cavity.

539
00:29:03,241 --> 00:29:06,810
The colossal cosmic burp
pushed food far

540
00:29:06,911 --> 00:29:09,813
away from the supermassive
black hole, ending

541
00:29:09,914 --> 00:29:13,350
its all-you-can-eat binge
and stopping its growth.

542
00:29:14,452 --> 00:29:17,521
If an intermediate mass
black hole was this greedy,

543
00:29:17,622 --> 00:29:20,557
it would come to a similar end.

544
00:29:20,658 --> 00:29:24,762
It's no way to gain weight
and become supermassive.

545
00:29:24,863 --> 00:29:27,164
This is probably
not the way the earliest

546
00:29:27,265 --> 00:29:31,001
supermassive black holes grew
to such enormous size.

547
00:29:31,102 --> 00:29:33,737
Is there another way
supermassive black holes

548
00:29:33,838 --> 00:29:34,972
could have formed

549
00:29:35,073 --> 00:29:37,741
in the early universe
without having to overeat?

550
00:29:39,110 --> 00:29:43,514
Maybe black holes smashed
their way to being giant-sized.

551
00:30:00,365 --> 00:30:02,866
November 2018.

552
00:30:02,967 --> 00:30:04,968
Astronomers scanning hundreds of

553
00:30:05,069 --> 00:30:08,205
nearby galaxies in infrared
light spot

554
00:30:08,306 --> 00:30:10,440
something extraordinary.

555
00:30:12,977 --> 00:30:16,547
Some galaxies had not one
supermassive black hole,

556
00:30:16,648 --> 00:30:18,215
but two.

557
00:30:20,652 --> 00:30:22,986
Are these pairs
a clue to how supermassive

558
00:30:23,087 --> 00:30:27,291
black holes in the infant
universe got so big so fast?

559
00:30:28,660 --> 00:30:32,696
Seeing these infrared images
showing pairs of supermassive

560
00:30:32,797 --> 00:30:35,532
black holes at the centers
of galaxies

561
00:30:35,633 --> 00:30:39,102
and showing that
this could be very common

562
00:30:39,204 --> 00:30:41,638
just is mind-blowing to me.

563
00:30:41,739 --> 00:30:45,209
The reason we see pairs of
supermassive black holes

564
00:30:45,310 --> 00:30:48,545
is because two galaxies
merged together.

565
00:30:48,646 --> 00:30:51,748
In our picture of
how the universe works,

566
00:30:51,850 --> 00:30:56,687
galaxies start off as smaller
galaxies and grow by merging

567
00:30:56,788 --> 00:30:58,155
with other galaxies.

568
00:30:58,256 --> 00:31:00,891
So they'll be whooshing
around each other

569
00:31:00,992 --> 00:31:03,093
and tearing each other up.

570
00:31:03,194 --> 00:31:05,095
It's actually quite violent.

571
00:31:05,196 --> 00:31:08,265
When galaxies merge,
we think their central

572
00:31:08,366 --> 00:31:11,068
supermassive black holes
also merge,

573
00:31:11,169 --> 00:31:14,338
smashing into each other
and combining to build

574
00:31:14,439 --> 00:31:16,273
a larger black hole.

575
00:31:16,374 --> 00:31:18,575
Galaxy-scale mergers
can be one of the most

576
00:31:18,676 --> 00:31:22,112
efficient growth mechanisms
for supermassive black holes.

577
00:31:23,548 --> 00:31:25,449
Maybe, in the early universe,

578
00:31:25,550 --> 00:31:28,619
black holes of stellar
or intermediate mass

579
00:31:28,720 --> 00:31:31,822
merged repeatedly,
getting heavier

580
00:31:31,923 --> 00:31:35,792
and heavier until
they became super massive.

581
00:31:38,062 --> 00:31:39,730
We don't really know how common

582
00:31:39,831 --> 00:31:42,599
supermassive black hole mergers
were in the early universe,

583
00:31:42,700 --> 00:31:45,269
but we think they were more
common than they are today,

584
00:31:45,370 --> 00:31:48,038
because galaxies were
closer together.

585
00:31:48,139 --> 00:31:51,875
It would have taken
millions of mergers to build up

586
00:31:51,976 --> 00:31:55,746
the largest supermassive
black holes we see today,

587
00:31:55,847 --> 00:31:57,981
which could have been
a tall order.

588
00:32:03,888 --> 00:32:05,989
There's another problem, too.

589
00:32:06,090 --> 00:32:07,891
We've never witnessed
a supermassive

590
00:32:07,992 --> 00:32:09,726
black hole merger in the act.

591
00:32:09,827 --> 00:32:13,030
We've seen supermassive black
holes on their way to merging,

592
00:32:13,097 --> 00:32:16,466
and we've seen ones that we
think had gone through mergers.

593
00:32:16,567 --> 00:32:19,169
But we haven't caught one
in the moment.

594
00:32:19,270 --> 00:32:22,005
As supermassive
black holes start merging,

595
00:32:22,106 --> 00:32:24,074
they spiral around each other,

596
00:32:24,175 --> 00:32:27,377
getting faster and faster
the closer they get.

597
00:32:29,480 --> 00:32:31,648
But for them
to finally merge together

598
00:32:31,749 --> 00:32:33,784
into a single black hole,

599
00:32:33,885 --> 00:32:36,553
they need to lose what
astronomers call

600
00:32:36,654 --> 00:32:38,655
orbital energy.

601
00:32:38,756 --> 00:32:42,326
The merger of supermassive
black holes means that

602
00:32:42,427 --> 00:32:43,927
their orbits have to decay

603
00:32:44,028 --> 00:32:45,929
for them to get closer
and closer together.

604
00:32:46,030 --> 00:32:48,231
So in order
for an orbit to decay,

605
00:32:48,333 --> 00:32:51,168
that orbital energy
has to go somewhere.

606
00:32:51,269 --> 00:32:52,669
To lose energy,

607
00:32:52,770 --> 00:32:56,473
the merging supermassive black
holes start disrupting

608
00:32:56,574 --> 00:32:58,842
the orbits of nearby stars,

609
00:32:58,943 --> 00:33:01,712
throwing them off their paths.

610
00:33:01,813 --> 00:33:04,181
So something small
and puny that weighs

611
00:33:04,282 --> 00:33:07,918
just one sun like our own star
will often get in

612
00:33:08,019 --> 00:33:10,687
the path of these two
and just get rocketed out,

613
00:33:10,788 --> 00:33:15,726
potentially unbound and flung
out of the galaxy entirely.

614
00:33:15,827 --> 00:33:18,061
Each time
the supermassive black holes

615
00:33:18,162 --> 00:33:21,965
fling out a star,
they lose more orbital energy.

616
00:33:22,066 --> 00:33:24,468
They get closer and closer.

617
00:33:24,569 --> 00:33:26,503
But eventually,
they kicked out all the stars.

618
00:33:26,604 --> 00:33:28,338
There's nothing left.

619
00:33:28,439 --> 00:33:30,707
The merger stalls.

620
00:33:30,808 --> 00:33:33,076
Like two sweethearts
at a high school prom,

621
00:33:34,479 --> 00:33:38,882
the supermassive black holes
dance as close as they can,

622
00:33:38,983 --> 00:33:41,585
but physical contact
is not allowed.

623
00:33:43,554 --> 00:33:46,023
So these two black holes
could end up spiraling

624
00:33:46,124 --> 00:33:49,159
around each other for billions
and billions of years.

625
00:33:49,260 --> 00:33:51,194
This is called the final
parsec problem.

626
00:33:54,565 --> 00:33:57,834
In 1980,
there was a famous paper,

627
00:33:57,935 --> 00:34:00,003
which addressed this issue that

628
00:34:00,104 --> 00:34:02,272
supermassive black holes
can only get to

629
00:34:02,373 --> 00:34:05,776
within about one parsec, or
three light-years, of each other

630
00:34:05,877 --> 00:34:10,614
before they can't merge
or they stall.

631
00:34:10,715 --> 00:34:14,017
We believe that supermassive
black holes must merge.

632
00:34:14,118 --> 00:34:17,054
We know that galaxies merge,
and so if the black holes

633
00:34:17,155 --> 00:34:19,656
didn't merge, we'd see lots of
black holes floating around.

634
00:34:19,757 --> 00:34:21,535
And we don't... there's always
one in the middle.

635
00:34:21,559 --> 00:34:23,226
So how do they merge?

636
00:34:24,796 --> 00:34:27,931
In 2019, we found
something that appears

637
00:34:28,032 --> 00:34:30,967
to solve
the final parsec problem...

638
00:34:31,069 --> 00:34:33,303
A galaxy in the middle
of a merger

639
00:34:33,404 --> 00:34:36,573
that contains not two
supermassive black holes,

640
00:34:36,641 --> 00:34:38,308
but three.

641
00:34:38,409 --> 00:34:40,710
Three supermassive black holes.

642
00:34:40,812 --> 00:34:42,279
Now that's really cool.

643
00:34:42,380 --> 00:34:44,848
Sometimes you can have
three galaxies

644
00:34:44,949 --> 00:34:48,085
that are merging together in
a galaxy cluster.

645
00:34:48,186 --> 00:34:50,387
Then you have three
supermassive black holes.

646
00:34:50,488 --> 00:34:51,621
At this point is,

647
00:34:51,722 --> 00:34:53,457
it's virtually
impossible for there to be

648
00:34:53,558 --> 00:34:55,692
a final parsec problem.

649
00:34:55,793 --> 00:34:58,829
Here's how a third
black hole solves the final

650
00:34:58,930 --> 00:35:00,864
parsec problem.

651
00:35:00,965 --> 00:35:04,201
Two of the black holes orbit
closer and closer,

652
00:35:04,302 --> 00:35:07,304
ejecting stars to lose energy.

653
00:35:07,405 --> 00:35:10,607
Black hole number three
joins the action.

654
00:35:10,708 --> 00:35:13,243
Its gravitational pull
takes even

655
00:35:13,311 --> 00:35:15,846
more energy
from the orbiting pair.

656
00:35:15,947 --> 00:35:21,785
Eventually, they lose enough
orbital energy to collide.

657
00:35:21,886 --> 00:35:25,689
That third supermassive
black hole is just what's needed

658
00:35:25,756 --> 00:35:27,757
to transfer energy away from

659
00:35:27,859 --> 00:35:31,428
the two merging black holes
so that they can now merge into

660
00:35:31,529 --> 00:35:34,397
one single supermassive
black hole.

661
00:35:34,499 --> 00:35:37,534
Triple black hole events
may explain how

662
00:35:37,635 --> 00:35:40,737
the earliest supermassive
black holes grew

663
00:35:40,838 --> 00:35:42,305
to such enormous size.

664
00:35:42,406 --> 00:35:47,544
We've suspected
that three black holes

665
00:35:47,645 --> 00:35:51,848
may be necessary in order
to get black holes to merge,

666
00:35:51,949 --> 00:35:54,084
but we've never had
any evidence for it.

667
00:35:54,185 --> 00:35:57,587
But now, this might provide
a direct picture

668
00:35:57,688 --> 00:36:02,325
of three black holes
caught in the act itself.

669
00:36:02,426 --> 00:36:05,595
If we have a picture
of this happening now,

670
00:36:05,696 --> 00:36:09,866
then it certainly happened in
the early universe and might

671
00:36:09,967 --> 00:36:14,204
explain how the biggest black
holes got so big so quickly.

672
00:36:15,706 --> 00:36:18,275
Final proof will come
when we witness a merger

673
00:36:18,376 --> 00:36:19,376
being completed.

674
00:36:20,678 --> 00:36:25,382
Scientists are also
investigating invisible forces

675
00:36:25,483 --> 00:36:26,983
at the beginning of
the universe.

676
00:36:27,051 --> 00:36:29,886
Did something we can't see boost

677
00:36:29,987 --> 00:36:33,023
the size of the first
supermassive black holes?

678
00:36:43,968 --> 00:36:47,470
One of the greatest
mysteries in cosmology is how

679
00:36:47,572 --> 00:36:53,043
the first supermassive black
holes got so large so quickly.

680
00:36:53,144 --> 00:36:56,780
We suspect mergers could help
explain their size,

681
00:36:56,881 --> 00:36:59,382
and we know all types
of black holes

682
00:36:59,483 --> 00:37:01,618
can grow by feeding,

683
00:37:01,719 --> 00:37:03,687
but we need more clues.

684
00:37:03,788 --> 00:37:07,924
There's still so much we don't
know about the early universe.

685
00:37:08,025 --> 00:37:10,293
The further out
we look in the universe,

686
00:37:10,394 --> 00:37:13,129
the less familiar
the universe becomes.

687
00:37:13,231 --> 00:37:19,436
And so the more and more
interesting and new physics

688
00:37:19,537 --> 00:37:22,672
you need to involve in order
to explain these very

689
00:37:22,773 --> 00:37:25,208
strange observations.

690
00:37:25,309 --> 00:37:27,043
The puzzle of fast-growing,

691
00:37:27,144 --> 00:37:30,880
supermassive black holes in
the infant universe now takes

692
00:37:30,982 --> 00:37:34,484
physicists somewhere new,
to the little

693
00:37:34,585 --> 00:37:37,387
understood realm of
magnetic fields.

694
00:37:38,789 --> 00:37:41,157
The thing about magnetic fields
is they're hard.

695
00:37:41,259 --> 00:37:43,379
They're hard to calculate,
they're hard to understand.

696
00:37:43,461 --> 00:37:45,862
They're sort of the elephant
in the room for astronomers.

697
00:37:45,963 --> 00:37:47,364
We know they're there, but we'd

698
00:37:47,465 --> 00:37:49,532
really rather not talk
about them.

699
00:37:49,634 --> 00:37:52,402
It's only recently that
people are incorporating

700
00:37:52,503 --> 00:37:55,972
magnetic fields into their
models of galaxy formation,

701
00:37:56,073 --> 00:38:00,010
and therefore, maybe it's under
the influence of these fields

702
00:38:00,111 --> 00:38:02,846
that somehow these supermassive
black holes are formed.

703
00:38:04,315 --> 00:38:07,017
To investigate how
magnetic fields influenced

704
00:38:07,118 --> 00:38:09,052
early supermassive black holes,

705
00:38:09,153 --> 00:38:12,055
we must look back
at the very beginning.

706
00:38:12,156 --> 00:38:15,125
Soon after the Big Bang,

707
00:38:15,226 --> 00:38:18,695
the first particles form,
cool, and become

708
00:38:18,796 --> 00:38:20,597
electrically charged.

709
00:38:20,698 --> 00:38:21,931
Things were very different,

710
00:38:22,033 --> 00:38:23,667
radically different
than they are now.

711
00:38:23,768 --> 00:38:25,468
Particles were whizzing
by each other.

712
00:38:25,569 --> 00:38:26,870
Everything was charged.

713
00:38:26,971 --> 00:38:29,372
It was just a very
different landscape.

714
00:38:29,473 --> 00:38:32,575
There are no stars yet,
not even atoms.

715
00:38:32,677 --> 00:38:35,745
But some scientists think
moving charged

716
00:38:35,846 --> 00:38:39,482
particles created
the first magnetic fields.

717
00:38:39,583 --> 00:38:40,861
Magnetic fields were essentially

718
00:38:40,885 --> 00:38:42,952
everywhere in the
early universe.

719
00:38:43,054 --> 00:38:45,855
Those magnetic fields
would have extended extremely

720
00:38:45,956 --> 00:38:49,192
large distances,
like a very finely

721
00:38:49,293 --> 00:38:52,128
spun web all through
the early universe.

722
00:38:53,364 --> 00:38:58,234
Gradually, atoms form
and gather into clouds of gas.

723
00:38:58,336 --> 00:39:00,103
These will become the first

724
00:39:00,204 --> 00:39:04,808
galaxies and their
supermassive black holes.

725
00:39:04,909 --> 00:39:08,111
During this time,
magnetic fields change.

726
00:39:08,212 --> 00:39:11,614
They bunch together
around the forming galaxies.

727
00:39:11,716 --> 00:39:12,882
But we don't know how.

728
00:39:12,983 --> 00:39:15,151
The thing
with magnetic fields is

729
00:39:15,252 --> 00:39:17,387
they're extremely
hard to predict,

730
00:39:17,488 --> 00:39:21,124
and you need to do really hard
calculations that, even now,

731
00:39:21,225 --> 00:39:22,926
we're only just starting to do.

732
00:39:23,994 --> 00:39:27,130
2017... scientists design

733
00:39:27,231 --> 00:39:28,865
a groundbreaking computer model

734
00:39:28,966 --> 00:39:33,036
that simulates patterns of
magnetism developing over time.

735
00:39:33,137 --> 00:39:38,007
The images show lines of
magnetic force getting stronger

736
00:39:38,109 --> 00:39:41,411
and more focused across
a vast region of space.

737
00:39:41,512 --> 00:39:45,148
Some astronomers think these
emerging magnetic field lines

738
00:39:45,216 --> 00:39:49,686
help shape early galaxies and
the supermassive black holes

739
00:39:49,787 --> 00:39:51,354
at their cores.

740
00:39:51,455 --> 00:39:55,558
Magnetic fields have this
ability to push material around.

741
00:39:55,659 --> 00:39:59,629
So one possibility is
they could actually help push

742
00:39:59,730 --> 00:40:02,065
or funnel material in towards

743
00:40:02,166 --> 00:40:05,702
a growing black hole and help
it grow faster than it would

744
00:40:05,803 --> 00:40:07,404
do otherwise.

745
00:40:07,505 --> 00:40:10,240
In today's universe,
we know magnetic fields

746
00:40:10,341 --> 00:40:13,843
around planets can
deflect dust particles.

747
00:40:13,944 --> 00:40:16,045
On much larger scales,

748
00:40:16,147 --> 00:40:19,349
matter may also have been
channeled into the centers of

749
00:40:19,450 --> 00:40:21,584
galaxies of the early universe.

750
00:40:21,685 --> 00:40:23,052
Were the magnetic fields of

751
00:40:23,154 --> 00:40:25,855
these early galaxies a conduit
that you could get matter

752
00:40:25,956 --> 00:40:28,691
dumped more and more into
the middle and maybe build up

753
00:40:28,793 --> 00:40:29,926
a really big black hole?

754
00:40:31,429 --> 00:40:33,463
Scientists are just
starting to figure out

755
00:40:33,564 --> 00:40:37,801
the effects of magnetism at
the beginning of the universe,

756
00:40:37,902 --> 00:40:40,370
but it could have been one of
several mechanisms that

757
00:40:40,471 --> 00:40:42,605
influenced the size of early

758
00:40:42,706 --> 00:40:45,508
supermassive black holes.

759
00:40:45,609 --> 00:40:48,478
We have lots of ideas
for how you might be able

760
00:40:48,579 --> 00:40:50,447
to form supermassive
black holes,

761
00:40:50,548 --> 00:40:54,184
but until we see actual
mechanisms in action, we just

762
00:40:54,285 --> 00:40:58,488
can't really say which of them
are the most important routes.

763
00:40:58,589 --> 00:41:01,891
Maybe some other mechanism
we haven't even thought of

764
00:41:01,992 --> 00:41:03,359
explains how the early

765
00:41:03,461 --> 00:41:08,164
supermassive black holes
got so big so fast.

766
00:41:08,265 --> 00:41:10,767
Hopefully, one day,
these monsters of

767
00:41:10,868 --> 00:41:15,138
the cosmos will reveal
their secrets to us.

768
00:41:15,239 --> 00:41:18,508
Supermassive black hole
research is utterly

769
00:41:18,609 --> 00:41:21,077
mind-blowing to me.
I mean, this is so cool.

770
00:41:21,178 --> 00:41:23,513
It's important
to explain how these early

771
00:41:23,614 --> 00:41:25,582
supermassive black holes formed

772
00:41:25,683 --> 00:41:29,018
in order to have a really
concrete understanding of how

773
00:41:29,119 --> 00:41:30,353
the universe works.

774
00:41:32,223 --> 00:41:35,325
Supermassive black holes are
the great engines of cosmic

775
00:41:35,426 --> 00:41:38,361
change... they're enormous
points of matter,

776
00:41:38,462 --> 00:41:40,663
and because
they're just so massive,

777
00:41:40,764 --> 00:41:43,433
they can sculpt
the evolution of galaxies.

778
00:41:43,534 --> 00:41:44,968
They're the master key

779
00:41:45,069 --> 00:41:48,338
to most of the unsolved
mysteries in physics.

780
00:41:48,439 --> 00:41:50,106
We have a chance here

781
00:41:50,207 --> 00:41:52,375
to understand supermassive
black holes

782
00:41:52,476 --> 00:41:55,345
so that we can understand
the formation of galaxies,

783
00:41:55,446 --> 00:41:58,147
the generation of stars like
our sun, and maybe even

784
00:41:58,249 --> 00:41:59,616
the appearance of life.

785
00:41:59,640 --> 00:42:01,640

786
00:42:01,690 --> 00:42:06,240
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