All language subtitles for How the Universe Works (2021) - S09E09 - Birth of the Monster Black Holes_track3_[eng]

ROWE: Supermassive black holes,

the engines that power
our universe.

Supermassive black holes are
one of the major players

in the evolution of galaxies.

THALLER: With no supermassive
black holes,

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

ROWE: They're the driving force
at the heart

of nearly every galaxy
in the cosmos.

They are the most monstrous and
scary and bizarre aspects of

our world,
which just fascinates me.

ROWE: Now, a new
mystery has emerged

about the oldest supermassive
black holes.

TREMBLAY: We see supermassive
black holes in

the very early universe.

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

ROWE: We have clues about
their formation.

But can we solve the mystery

of this supermassive
growth spurt?

[electricity buzzing]

♪♪

ROWE: 2017.

Scientists gazing deep into

the distant universe
discover something

completely unexpected --

A vast supermassive black
hole dating

from the earliest days
of the universe.

MINGARELLI: This was 690 million
years after the Big Bang.

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

Finding a supermassive black
hole in the early universe is

like finding an NFL
defensive lineman playing

in peewee football.

Something that big shouldn't
exist that young.

ROWE: The supermassive black
hole wasn't just super early.

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

HOPKINS: In just a few hundred
million years,

the universe has somehow been
able to collapse nearly

a billion suns' worth of

material into
a giant black hole.

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

ROWE: We measure black holes
by the mass of our sun --

Solar masses.

Regular, or stellar,
black holes are a few

to a hundred solar masses.

Supermassive black holes weigh
from 100,000 to billions

of suns.

And scientists have now found
over 100 of these monsters in

the early universe.

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

after the Big Bang.

It was kind of freakish,
to be honest,

but then to find that there's
whole populations

of these things that exist
and are well

in place at the earliest times

that we can look at
was truly shocking.

ROWE: We believe
supermassive black holes might

help explain the evolution
and the destiny of the universe.

Astronomers are striving
to understand them.

OLUSEYI:
Understanding the origin

of supermassive black holes
and how

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

something that would change all
of astronomy and astrophysics.

How do you get something
that massive to

form in such a short amount
of time?

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

we have to start small,
by asking

how regular stellar
black holes form.

FILIPPENKO: Black holes form
through the collapse of stars.

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

and it'll collapse to
form a black hole.

[explosion blasts]

A really massive star dies in
a violent supernova explosion,

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

collapses into a black hole.

The bigger the star was,

the bigger the black hole
is to start with.

ROWE: Were the stars
of the early universe

big enough to collapse into
supermassive black holes?

The very early universe was
much different than

the university you see
around us today.

It was filled entirely with
hydrogen and helium gas.

ROWE: This gas amassed
into giant clouds,

which collapsed
under their own gravity.

Nuclear fusion ignited
the dense cores,

and the first stars were born.

Now, we think that these
earliest clouds of gas probably

made bigger stars than clouds

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

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

Population III stars that
were just utterly massive.

ROWE: Population III stars are
the oldest category of star.

Like stellar dinosaurs,

they dominated the universe
a long time ago.

Now, they're extinct.

HOPKINS: They'd be weird stars.

They would be incredibly
bright in the ultraviolet

and have very unique signatures

that are very different
from stars today,

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

they would be very short-lived.

ROWE: These first stars
lived fast and died young...

[explosion blasts]

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

But were they supermassive
black holes?

When a star blows up,
when it goes supernova,

most of the mass
is ejected away.

It just goes flying out,

leaving a dense neutron star
or perhaps a black hole.

But it won't have much
mass, because

most of that mass was
blown away.

Even though Population III
stars in the infant universe

were very large,

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

behind when they exploded.

Perhaps if we can skip
the supernova step,

that might be one pathway to
understanding how supermassive

black holes formed.

Could a dying star's entire
mass collapse

into a black hole?

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

The Fireworks Galaxy has that

flashy name,
because when you look at it,

there are all these supernova
explosions going off

and, um, making quite a show.

ROWE: Recently, astronomers
were keeping an eye on

one extremely bright star
in the Fireworks Galaxy.

PLAIT: This star
is exactly the kind

that we know explodes
as a supernova.

Astronomers expected it
to explode,

but then it did something
even weirder.

Astronomy is so wonderful,
because sometimes you see things

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

We saw an entire star
just disappear.

ROWE: In 2007, the star
looked like this.

By 2015, it had
completely vanished.

There was no flare

or debris
from a supernova explosion.

So what the heck is going on?

PLAIT: It turns out that not
every massive star blows up

with all the fireworks
of a normal supernova.

You can get what's called
a failed supernova.

ROWE: A supernova fails
when the shockwave

generated inside a collapsing
star can't escape.

THALLER: In some cases,
when the star is very massive,

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

the star by the time
the star itself

collapses into a black hole,

then you have
a failed supernova.

ROWE: The Fireworks Galaxy star
may have been massive enough to

smother its own explosion
before collapsing

to form a black hole.

THALLER: Everything collapses
into the black hole.

You can actually
have a black hole

with all the mass of
the original star.

ROWE:
Back in the early universe,

could the enormous
Population III stars have died

as failed supernovas,

leaving behind supermassive
black holes?

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

a good contender for
the precursor to supermassive

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

FILIPPENKO: Even
the most massive stars are only

a couple of hundred times
more massive than our sun,

whereas a supermassive black
hole is millions or billions of

times the mass of our sun.

ROWE:
Early supermassive black holes

can't have formed
from collapsing stars.

Even giant stars aren't
massive enough.

So is there some other path to
being supermassive?

Were stellar black holes

cosmic bodybuilders on
a fast-track bulking program?

ROWE: How did
supermassive black holes in

the early universe get
so large so quickly?

We ruled out the idea
that they were

created from the collapse of
very large stars.

Maybe they started out
as smaller,

stellar mass black holes
and grew to be supermassive

by eating.

TREMBLAY: Black holes
are not fussy eaters.

They'll consume anything that
comes in their path.

You know, gas, planets, stars.

It doesn't matter,
and everything that they

consume adds mass
to the black hole.

ROWE: We've spotted
a stellar mass black hole

currently eating
in our Milky Way Galaxy.

15 times the mass of the sun,

Cygnus X-1 is steadily feeding

off the material
that swirls around it.

MINGARELLI: Some black holes are
fed through things called

accretion disks.

It's kind of like the rings
around Saturn.

There's this thick
or thin disk of

material around the black hole
that feeds it.

ROWE: Cygnus X-1's
secretion disc gets

constant refills
from a nearby source,

a vast star 20 times the mass

of the sun called
a blue supergiant.

The black hole has been
feeding on gas

from this star for about
five million years.

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

The answer is gravity, these are

very massive objects, and
anything that comes within

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

ROWE: The more mass
a black hole gains, the greater

its gravity and the more food
it attracts.

PLAIT: A black hole growing
is a little bit

like a snowball rolling
down a hill.

The bigger the snowball gets,
the more snow it

can accumulate,
and so the bigger it gets.

It's a runaway effect.

ROWE: But even if Cygnus X-1
follows this runaway

growth trajectory,

it still may never reach
supermassive status.

The black holes of
the early universe must

have fed at a much faster rate.

The biggest issue
is how do you have

enough time in the early
universe to go

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

something that's supermassive?

ROWE: GRS 1915 is another
stellar mass black hole.

It's a greedy eater,
accreting at up to

40 times the rate of Cygnus X-1,

and when something gobbles
food that quickly,

it can begin to overheat.

MINGARELLI: The black hole is
accreting a lot of material,

and as it's eating,

the accretion disc
really heats up to very

high temperatures.

And at those high temperatures,
you can get

a lot of light
coming out of the system.

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

the brighter it shines.

ROWE: This stellar black hole
sometimes eats so much

so quickly, its accretion disk

pushes out radiation
almost a million times brighter

than our sun,

but this brightness has
a serious consequence.

It stops the black hole from
eating and growing larger.

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

quickly as possible,
you would just keep

feeding me hamburgers nonstop
or whatever, but...

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

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

the neighborhood, and then also,

they start shining out
so much stuff

that it pushes away much
of the food.

ROWE:
The brightness, or luminosity,

gets so intense, it pushes away

incoming material,

a sort of safety valve called
the Eddington Limit.

So in many ways,
the Eddington rate could be

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

It could be a governor that
prevents black holes from

growing even faster

by just dumping more and more
gas onto it.

Eventually, you're gonna hit
that Eddington limit,

and that more gas

that you're dumping on won't
actually reach the black hole.

ROWE: This cosmic method
of portion control

means that
stellar black holes in

the early universe couldn't
have gained weight fast enough

to become supermassive.

SUTTER: Black holes
need time to grow.

They need to feed.
They need to eat.

Maybe you need
to skip a few steps.

Maybe you need to start at
a medium size or bigger

in order to get to supermassive
by the time we observe it.

ROWE: So was there another
type of black hole

in the early universe?

Something big enough
to grow supermassive

in the time available?

ROWE: In 2017,
astronomers studied

a dense star cluster called

47 Tucanae on the outskirts
of our own galaxy.

They detected 25 pulsars,

bodies that spin
and emit radiation

like cosmic lighthouses.

SUTTER: These pulsars are all
orbiting a central object.

And even though we couldn't
see the central object itself,

we could watch the behavior in
the orbits of all these pulsars

around it,
and we could figure out

how big that central object was.

Well, when you do the math,

you come up with something
that is about 1,500 to 2,000

times the mass of the sun
that's actually hidden in

the heart of that
globular cluster.

ROWE: So what is
the invisible object?

Whatever's lurking at
the center of 47 Tucanae has

to be big,
and it has to be black.

ROWE: Astronomers think
it's a large black hole.

At 1,500 times

the mass of the sun, the object

is much bigger than a regular
stellar black hole,

but too small to
be supermassive.

Could it be what's known as
an intermediate mass black hole?

It's extremely hard to find any

of these intermediate
mass black holes.

ROWE: This rare category
of black hole

ranges between 100
and 100,000 solar masses.

At that size, they may have

been large enough to become
supermassive very quickly.

Intermediate mass black holes
could be what give

supermassive black holes
a head start in life.

ROWE: Astronomers
have never seen

an intermediate mass black hole,

but now, we've heard one,
calling to us

from across the universe.

ROWE: Astronomers search for
intermediate mass black holes.

They may have been large enough

to act as seeds
for the first supermassive

black holes.

Yet so far,
they've escaped discovery.

They're like
the missing link. And I

mean that for real.
They're missing.

Imagine you're an alien who's
arrived on the planet Earth,

and you know very little
about the human species,

and when you look around,
you only notice tiny,

tiny little children
and grown adults.

You don't see any
adolescents, right?

And intrinsically, you know
that the tiny little

children grow up to be
full-size adults.

But you don't see how
they got there, right?

You don't see the intermediate
stages of growth.

That would be really,
really weird, right?

That is the case for
supermassive black holes.

So it's like a universe
without teenagers.

ROWE: Or that's how it looked,
until September 2020.

Scientists studying
gravitational waves

picked up the signal of
an extreme event

in the distant universe.

What researchers are looking for

are things called
gravitational waves.

They're like ripples
in space itself.

Most signals sound
a little bit like a chirp.

It's a noise that's
very characteristic.

It goes a bit, like,
sort of whoop!

[whooping noise]

But this particular event
was so extreme

and so sudden, it just sounded
more like a thud.

[faint thud]

ROWE: This faint thud
from halfway across the universe

is music to the ears of
intermediate black hole hunters,

because its pitch
can mean only one thing.

This could only have been
created by two

really massive black holes
colliding into each other

and producing
a combined black hole with

a mass that's 142 times
the mass of our sun.

So that, is for the first time,

getting into this intermediate
mass black hole regime.

ROWE:
This is the first confirmed

observation of
an intermediate black hole.

Finding direct evidence
like this for

an intermediate mass black
hole is absolutely fantastic.

ROWE: Now that we're certain
intermediate black holes exist,

could they help explain
the origin of supermassive

black holes
in the early universe?

These intermediate black holes
really could be

the first seeds of
the supermassive black holes.

You would need something like
that to form really big,

really early to even begin to
explain these very massive,

supermassive black holes
that have formed

just a short time
after the Big Bang.

ROWE: How do intermediate black
holes form in the first place?

The recently discovered one
came from

the collision of
two smaller black holes.

They may also form
in giant clouds of gas.

It could be that in
the earlier universe,

you can just have large
clouds of gas that can lose

enough energy quickly enough to

just spontaneously collapse and
form a black hole of this size.

HOPKINS: The enormous cloud of
gas contracts and gets denser

and denser, the way it would if
it was starting to form stars.

But it's somehow able to
remain coherent

and collapse
into one giant object

that forms an intermediate
mass black hole.

ROWE: A giant gas cloud
undergoing a direct collapse

down to
an intermediate mass black hole

would be a rare sight.

You think it would go giant
cloud, slowly collapsing,

black hole, but instead,

it's more like, giant cloud,
ahhhh!!!! Black hole.

So one day, you see this
massive gas complex, and then

you blink, and it's collapsed,

and now you're face-to-face
with a big black hole.

ROWE: At least,
that's the theory.

Getting a black hole
to form from

the direct collapse of
a gas cloud is very tricky.

ROWE: Gas clouds tend
to split up and collapse

into a multitude of stars --
Collapsing into

one object would take
unique conditions.

One possible scenario involves
two neighboring galaxies.

The first, a young protogalaxy,

a gas cloud yet to form stars.

Next door sits a larger galaxy.

It's forming so many stars,

radiation is bursting out
all over its young neighbor.

Because they're in
close proximity,

the energy from the large galaxy

prevents the smaller galaxy
from forming its stars,

so that means that
it will continue

to collapse in cloud form
before moving to

star formation.

ROWE: The gas cloud becomes
large and dense enough,

the gravity eventually pulls
it in on itself.

When it can't ignite into stars,

the collapse creates
an intermediate mass black hole.

SUTTER: I think this idea is
very intriguing.

I don't know if it's
physically possible,

but then again,

there's a lot we don't know
about the early universe.

ROWE: Whichever way intermediate
mass black holes form,

they seem like a good way to
start explaining supermassive

black holes
in the early universe.

The question is, then,
how do they grow?

How do you start
from this seed and end up,

you know, with something that's
a billion times the mass of

the sun?

ROWE: Maybe early intermediate
mass black holes had

enormous appetites,

gorging themselves to
a supermassive state, feeding on

the biggest meals
our universe can serve up.

♪♪

ROWE: Astronomers want
to know how the earliest

supermassive black holes got
so big so quickly.

Could they have started
as intermediate

mass black holes that devoured
supersized meals?

It's possible that these
intermediate mass black holes

could form in an exceptionally
rare environment where it can

accrete new material
at an enormously high rate.

ROWE: So far,
we only have direct

evidence of one intermediate
mass black hole,

and we can't yet detect
how it eats and grows.

But we could look at much
larger black holes for clues.

In 2019, astronomers searched
for supermassive

black holes that are
actively feeding.

They pinpointed 12 quasars

from the beginning of
the cosmos.

HOPKINS: Quasars are among
the brightest objects

we know of in the universe.

And they're what happens when
a supermassive black hole at

the center of a galaxy
is swallowing

up gas and dust, and that
generates a tremendous amount

of energy and luminosity
that we can see.

ROWE: Surrounding
these early galaxies are

enormous gas reservoirs called
hydrogen halos.

PLAIT: This is great,
because that acts

as fuel for those supermassive
black holes.

Cold gas can stream into those
black holes and feed them.

ROWE:
These huge halos of cold gas

are also the building blocks
of stars.

TREMBLAY: These enormous,
pristine halos

of hydrogen around
early galaxies,

they're gonna be reservoirs
to power star formation.

ROWE: Star formation
is a violent process

that can create turbulence
in a galaxy.

That turbulence makes the gas
fall toward the black hole,

and then that makes
the black hole even bigger.

ROWE: Hydrogen halos
might have spoon fed

early supermassive black holes.

This process may have
also helped

intermediate mass black holes
grow quickly.

Could the largest
black holes show us

other, more drastic ways
to put on weight?

In October 2019,
astronomers used telescopes to

explore a remarkably clear
galaxy called M77.

Because this galaxy
is so near to us,

we can study its central engine
in really exquisite detail at

very, very fine resolution.

SUTTER: Not only do you see

the bright core,
the bright nucleus,

but you can see spiral arms.

You can see structures
in the galaxy.

You can see how the whole
galaxy is arranged.

ROWE:
When we examined M77's central

supermassive black hole,
we saw something extraordinary.

Its food was coming
not from one,

but two accretion disks
spinning in

opposite directions.

Normally around a black hole,
all of the gas is spinning in

roughly the same direction,

and that creates kind of
a slow infall of gas

and slow feeding -- here,

we've got a case where
some of it's going

one way, the other is going
the other way.

This is very unstable and can
create opportunities for lots

of gas to get gobbled up
by that black hole.

ROWE: The material in the disks

is one enormous
ready-to-eat meal,

but dinner will not be served
until the outer disk

slows down.

HOPKINS: If there's a black hole
at the center of a galaxy,

and you're orbiting around it

fast enough to maintain
your orbit,

you're never going to fall in.

You're just going to orbit
forever, and you're just going

to spin around,
just like the way the Earth

is going around the sun.

What needs to happen
if you wanna fall in,

is to slow down your speed.

ROWE: The outer accretion disk
will gradually slow down

and orbit more tightly against
the inner disk.

Dangerous collisions of
the counter-rotating

material will start to occur.

SUTTER: The double accretion
disk is like drinking

from two soda fountains at
the same time.

It's great while it lasts,

but you're building up some
serious gas that is just gonna

blow the whole thing away.

ROWE:
In just a few 100,000 years,

the double disks will
catastrophically collide,

and their entire contents
will fall

into the central
supermassive black hole.

It will devour everything
in one gulp,

generating a colossal
cosmic burp.

In February of 2020,
in the Ophiuchus Galaxy Cluster,

we saw the damage
a cosmic burp can do.

PLAIT: The Ophiuchus Galaxy
Cluster is a collection of

a huge number of galaxies,
all bound together by gravity.

And there's gas in between
these galaxies.

And when astronomers
looked at that gas in detail,

what they found was a huge
arcing structure in it that

they realized was
the edge of a cavity.

SUTTER: There is a massive hole
in the gas that is

over 15 times bigger than
the entire Milky Way Galaxy.

Something frightening had to
happen to carve this void out.

PLAIT: The size of this bubble
is kind of stomping my brain.

We are talking about

a hole in this gas that is over
a million light-years wide.

ROWE: The burp that created
this cavity

must have been
astoundingly powerful.

PLAIT: There are a lot
of ideas about this,

but there's only one that
really can explain it.

And that's
a supermassive black hole.

A supermassive black hole
that suddenly got very greedy.

In order to drive an energetic
event like this,

the black hole needs to eat --
Not just one meal.

It needs to eat thousands of
meals at the exact same time.

It needs to go
to an all-you-can-eat

intergalactic buffet.

Sometime in the distant past,

this black hole must have had
a huge episode of just gorging

on material falling in --
That got superhot,

blew out a tremendous
amount of material in jets,

beams that shot out
from the poles of the disk.

And that's what basically
pushed its way out of that gas,

forming this enormous cavity.

ROWE: The colossal cosmic burp
pushed food far

away from the supermassive
black hole, ending

its all-you-can-eat binge
and stopping its growth.

If an intermediate mass
black hole was this greedy,

it would come to a similar end.

It's no way to gain weight
and become supermassive.

This is probably
not the way the earliest

supermassive black holes grew
to such enormous size.

ROWE: Is there another way
supermassive black holes

could have formed

in the early universe
without having to overeat?

Maybe black holes smashed
their way to being giant-sized.

[explosion blasts]

ROWE: November 2018.

Astronomers scanning hundreds of

nearby galaxies in infrared
light spot

something extraordinary.

Some galaxies had not one
supermassive black hole,

but two.

Are these pairs
a clue to how supermassive

black holes in the infant
universe got so big so fast?

Seeing these infrared images
showing pairs of supermassive

black holes at the centers
of galaxies

and showing that
this could be very common

just is mind-blowing to me.

The reason we see pairs of
supermassive black holes

is because two galaxies
merged together.

MINGARELLI: In our picture of
how the universe works,

galaxies start off as smaller
galaxies and grow by merging

with other galaxies.

So they'll be whooshing
around each other

and tearing each other up.

It's actually quite violent.

ROWE: When galaxies merge,
we think their central

supermassive black holes
also merge,

smashing into each other
and combining to build

a larger black hole.

Galaxy-scale mergers
can be one of the most

efficient growth mechanisms
for supermassive black holes.

ROWE: Maybe,
in the early universe,

black holes of stellar
or intermediate mass

merged repeatedly,
getting heavier

and heavier until
they became super massive.

STRAUGHN: We don't
really know how common

supermassive black hole mergers
were in the early universe,

but we think they were more
common than they are today,

because galaxies were
closer together.

ROWE: It would have taken
millions of mergers to build up

the largest supermassive
black holes we see today,

which could have been
a tall order.

There's another problem, too.

We've never witnessed
a supermassive

black hole merger in the act.

We've seen supermassive black
holes on their way to merging,

and we've seen ones that we
think had gone through mergers.

But we haven't caught one
in the moment.

ROWE: As supermassive
black holes start merging,

they spiral around each other,

getting faster and faster
the closer they get.

But for them
to finally merge together

into a single black hole,

they need to lose what
astronomers call

orbital energy.

The merger of supermassive
black holes means that

their orbits have to decay

for them to get closer
and closer together.

So in order
for an orbit to decay,

that orbital energy
has to go somewhere.

ROWE: To lose energy,

the merging supermassive black
holes start disrupting

the orbits of nearby stars,

throwing them off their paths.

HOPKINS: So something small
and puny that weighs

just one sun like our own star
will often get in

the path of these two
and just get rocketed out,

potentially unbound and flung
out of the galaxy entirely.

ROWE: Each time
the supermassive black holes

fling out a star,
they lose more orbital energy.

They get closer and closer.

But eventually,
they kicked out all the stars.

There's nothing left.

ROWE: The merger stalls.

Like two sweethearts
at a high school prom,

the supermassive black holes
dance as close as they can,

but physical contact
is not allowed.

So these two black holes
could end up spiraling

around each other for billions
and billions of years.

This is called the final
parsec problem.

MINGARELLI: In 1980,
there was a famous paper,

which addressed this issue that

supermassive black holes
can only get to

within about one parsec, or
three light-years, of each other

before they can't merge
or they stall.

We believe that supermassive
black holes must merge.

We know that galaxies merge,
and so if the black holes

didn't merge, we'd see lots of
black holes floating around.

And we don't -- there's always
one in the middle.

So how do they merge?

ROWE: In 2019, we found
something that appears

to solve
the final parsec problem --

A galaxy in the middle
of a merger

that contains not two
supermassive black holes,

but three.

MINGARELLI: Three supermassive
black holes.

Now that's really cool.

Sometimes you can have
three galaxies

that are merging together in
a galaxy cluster.

Then you have three
supermassive black holes.

At this point is,

it's virtually
impossible for there to be

a final parsec problem.

ROWE: Here's how a third
black hole solves the final

parsec problem.

Two of the black holes orbit
closer and closer,

ejecting stars to lose energy.

Black hole number three
joins the action.

Its gravitational pull
takes even

more energy
from the orbiting pair.

Eventually, they lose enough
orbital energy to collide.

OLUSEYI: That third supermassive
black hole is just what's needed

to transfer energy away from

the two merging black holes
so that they can now merge into

one single supermassive
black hole.

ROWE: Triple black hole events
may explain how

the earliest supermassive
black holes grew

to such enormous size.

We've suspected
that three black holes

may be necessary in order
to get black holes to merge,

but we've never had
any evidence for it.

But now, this might provide
a direct picture

of three black holes
caught in the act itself.

If we have a picture
of this happening now,

then it certainly happened in
the early universe and might

explain how the biggest black
holes got so big so quickly.

ROWE: Final proof will come
when we witness a merger

being completed.

Scientists are also
investigating invisible forces

at the beginning of
the universe.

Did something we can't see boost

the size of the first
supermassive black holes?

ROWE: One of the greatest
mysteries in cosmology is how

the first supermassive black
holes got so large so quickly.

We suspect mergers could help
explain their size,

and we know all types
of black holes

can grow by feeding,

but we need more clues.

There's still so much we don't
know about the early universe.

SUTTER: The further out
we look in the universe,

the less familiar
the universe becomes.

And so the more and more
interesting and new physics

you need to involve in order
to explain these very

strange observations.

ROWE:
The puzzle of fast-growing,

supermassive black holes in
the infant universe now takes

physicists somewhere new,
to the little

understood realm of
magnetic fields.

The thing about magnetic fields
is they're hard.

They're hard to calculate,
they're hard to understand.

They're sort of the elephant
in the room for astronomers.

We know they're there, but we'd

really rather not talk
about them.

It's only recently that
people are incorporating

magnetic fields into their
models of galaxy formation,

and therefore, maybe it's under
the influence of these fields

that somehow these supermassive
black holes are formed.

ROWE: To investigate how
magnetic fields influenced

early supermassive black holes,

we must look back
at the very beginning.

Soon after the Big Bang,

the first particles form,
cool, and become

electrically charged.

Things were very different,

radically different
than they are now.

Particles were whizzing
by each other.

Everything was charged.

It was just a very
different landscape.

ROWE: There are no stars yet,
not even atoms.

But some scientists think
moving charged

particles created
the first magnetic fields.

Magnetic fields were essentially

everywhere in the
early universe.

PONTZEN: Those magnetic fields
would have extended extremely

large distances,
like a very finely

spun web all through
the early universe.

ROWE: Gradually, atoms form
and gather into clouds of gas.

These will become the first

galaxies and their
supermassive black holes.

During this time,
magnetic fields change.

They bunch together
around the forming galaxies.

But we don't know how.

PONTZEN: The thing
with magnetic fields is

they're extremely
hard to predict,

and you need to do really hard
calculations that, even now,

we're only just starting to do.

ROWE: 2017 -- scientists design

a groundbreaking computer model

that simulates patterns of
magnetism developing over time.

The images show lines of
magnetic force getting stronger

and more focused across
a vast region of space.

Some astronomers think these
emerging magnetic field lines

help shape early galaxies and
the supermassive black holes

at their cores.

Magnetic fields have this
ability to push material around.

So one possibility is
they could actually help push

or funnel material in towards

a growing black hole and help
it grow faster than it would

do otherwise.

ROWE: In today's universe,
we know magnetic fields

around planets can
deflect dust particles.

On much larger scales,

matter may also have been
channeled into the centers of

galaxies of the early universe.

Were the magnetic fields of

these early galaxies a conduit
that you could get matter

dumped more and more into
the middle and maybe build up

a really big black hole?

ROWE: Scientists are just
starting to figure out

the effects of magnetism at
the beginning of the universe,

but it could have been one of
several mechanisms that

influenced the size of early

supermassive black holes.

PONTZEN: We have lots of ideas
for how you might be able

to form supermassive
black holes,

but until we see actual
mechanisms in action, we just

can't really say which of them
are the most important routes.

ROWE: Maybe some other mechanism
we haven't even thought of

explains how the early

supermassive black holes
got so big so fast.

Hopefully, one day,
these monsters of

the cosmos will reveal
their secrets to us.

Supermassive black hole
research is utterly

mind-blowing to me.
I mean, this is so cool.

MINGARELLI: It's important
to explain how these early

supermassive black holes formed

in order to have a really
concrete understanding of how

the universe works.

Supermassive black holes are
the great engines of cosmic

change -- they're enormous
points of matter,

and because
they're just so massive,

they can sculpt
the evolution of galaxies.

They're the master key

to most of the unsolved
mysteries in physics.

We have a chance here

to understand supermassive
black holes

so that we can understand
the formation of galaxies,

the generation of stars like
our sun, and maybe even

the appearance of life.