Original subtitles

Supermassive black holes,

the engines that power our universe.

Supermassive black holes are one of the major players

in the evolution of galaxies.

With no supermassive black holes,

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

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.

Now, a new mystery has emerged

about the oldest supermassive black holes.

We see supermassive black holes in

the very early universe.

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

We have clues about their formation.

But can we solve the mystery

of this supermassive growth spurt?

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.

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.

The supermassive black hole wasn't just super early.

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

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.

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.

We believe supermassive black holes might

help explain the evolution and the destiny of the universe.

Astronomers are striving to understand them.

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.

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.

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.

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.

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.

Population III stars are the oldest category of star.

Like stellar dinosaurs,

they dominated the universe a long time ago.

Now, they're extinct.

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.

These first stars lived fast and died young...

...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.

Recently, astronomers were keeping an eye on

one extremely bright star in the Fireworks Galaxy.

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.

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?

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.

A supernova fails when the shockwave

generated inside a collapsing star can't escape.

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.

The Fireworks Galaxy star may have been massive enough to

smother its own explosion before collapsing

to form a black hole.

Everything collapses into the black hole.

You can actually have a black hole

with all the mass of the original star.

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.

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.

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?

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.

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.

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.

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.

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.

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.

The more mass a black hole gains, the greater

its gravity and the more food it attracts.

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.

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?

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.

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.

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.

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.

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.

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.

So was there another type of black hole

in the early universe?

Something big enough to grow supermassive

in the time available?

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.

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.

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.

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.

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.

Astronomers have never seen

an intermediate mass black hole,

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

from across the universe.

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.

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!

But this particular event was so extreme

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

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.

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.

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.

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.

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.

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.

At least, that's the theory.

Getting a black hole to form from

the direct collapse of a gas cloud is very tricky.

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.

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.

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.

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?

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.

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.

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.

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.

Surrounding these early galaxies are

enormous gas reservoirs called hydrogen halos.

This is great, because that acts

as fuel for those supermassive black holes.

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

These huge halos of cold gas

are also the building blocks of stars.

These enormous, pristine halos

of hydrogen around early galaxies,

they're gonna be reservoirs to power star formation.

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.

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.

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.

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.

The material in the disks

is one enormous ready-to-eat meal,

but dinner will not be served until the outer disk

slows down.

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.

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.

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.

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.

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.

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.

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.

The burp that created this cavity

must have been astoundingly powerful.

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.

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.

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.

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.

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.

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.

Maybe, in the early universe,

black holes of stellar or intermediate mass

merged repeatedly, getting heavier

and heavier until they became super massive.

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.

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.

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.

To lose energy,

the merging supermassive black holes start disrupting

the orbits of nearby stars,

throwing them off their paths.

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.

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.

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.

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?

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.

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.

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.

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.

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.

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?

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.

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.

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.

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.

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.

Those magnetic fields would have extended extremely

large distances, like a very finely

spun web all through the early universe.

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.

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.

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.

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?

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.

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.

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.

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.

Repair and Synchronization by Easy Subtitles Synchronizer 1.0.0.0