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Where Do Supermassive Black Holes Really Come From?

black holes are some of the most massive

objects in the known universe

they are spheroid regions of space from

which nothing can escape not even light

Sagittarius a is what scientists call

the black hole at the center of our

galaxy and it's huge

it's thought to be 4.6 million times the

mass of our Sun scientists call

Sagittarius a a supermassive black hole

which is the largest type of black hole

astronomers have found we see them in

the center of galaxies and observations

to this point suggest nearly all large

galaxies contain one besides these there

are two other types stellar and

intermediate stellar black holes are

formed by the gravitational collapse of

the star and are much smaller about five

to ten solar masses the Milky Way likely

contains a few hundred million stellar

black holes intermediate black holes are

just that in the middle between the two

other types they're too massive to be

formed by the collapse of a single star

but much smaller than those seen at the

center of galaxies they could be stellar

black holes that merge that could be the

result of the collision between massive

stars or that could be primordial black

holes formed just after the Big Bang

primordial black holes might also

explain something astrophysicists have

been wondering about for a while

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they were first proposed by Yakov Zelda

vich and Igor Novikov in 1966 and later

studied by Stephen Hawking since we

can't take a time machine back to the

Big Bang scientists are left with the

observations that can make now a huge

mystery in cosmology relates to the

origin of these supermassive black holes

see it's long been theorized but they

were once much smaller and grew by

consuming the matter around them but

many recent observations suggest that

this cannot be the case

some supermassive black hole seen in the

sky are so old that there wouldn't have

been enough time for them to form that

way other supermassive black holes have

been found in very small galaxies in

almost empty space weather isn't enough

material to form them galaxy NGC 1275

formed by physicists understanding of

how accretion works so how is this

happening a simple solution is that

supermassive black holes might have

actually come into existence before

almost anything else a new study from

the University of Tokyo supports this

idea the authors Masahiro Kawasaki and

Kaymer I examine if the conditions just

after the Big Bang can explain the

presence of very old supermassive black

holes

since these objects wouldn't have had

enough time to grow into their size they

asked could they have been formed by

fluctuations in the early universe

theoretical physicists think that

so-called

density fluctuations are responsible for

the structure of our universe today see

when we look at our universe now it is

not perfectly smooth matter is not

evenly distributed our earth for example

is about a thousand times more dense

than any average point in the universe

it's thought the tiny imperfections in

the early universe is density led to

what do we see now if you could look at

the energy density of the universe today

on extremely small scales you'd see it

still isn't uniform there are quantum

fluctuations in the fabric of space-time

itself normally these fluctuations

cancel out but during a very early

inflationary period of the universe not

all of them were able to cancel out

because of how fast space was expanded

this led to areas of the universe being

over dense and other areas being under

dense that results in the imperfections

we see in the Cosmic Microwave

Background today it's also thought that

some of these density fluctuations could

have produced primordial black holes

Kawasaki and var I suggest that regions

with a large enough concentration

subatomic particles could have collapsed

into black holes some of these could

have eventually became the supermassive

black holes we see today this theory

also explains how binary black holes

have been found some primordial black

holes could have simply became binary

systems in the early universe

this study matters because it changes

our perception of black holes maybe if

it weren't for them we might not have a

Milky Way galaxy at all

you