Black holes and galaxies formations.
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" . . . supermassive black holes with the mass of millions or billions of Suns are assumed
to reside in the cores of most galaxies, and they play a key role in current models
of how galaxies have formed over the past billions of years."
en.wikipedia.org
Correct.
Galaxies formations can have their source "black holes".
Why?
1- "A black hole of one solar mass (M☉) has a temperature of only 60 nanokelvins
(60 billionths of a kelvin) Hawking radiation" / Wikipedia /
2- A black hole has a temperature within a few millionths
of a degree above absolute zero / Oxford. Dictionary./
3- "Stellar black holes are very cold: they have a temperature of nearly absolute zero –
which is zero Kelvin, or −273.15 degrees Celsius. Supermassive black holes are even colder."
www.asc-csa.gc.ca
My conclusion:
The cold and infinite cosmic vacuum has the same temperature as black holes.
It means that so-called "black holes" are only parts of the infinite cosmic vacuum.
So-called "black hole" is other name of the cosmic vacuum.
And as was said " . . . they play a key role in current models of how galaxies have formed
over the past billions of years." as a process of quantum gravity going on for billions of years.
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" . . . supermassive black holes with the mass of millions or billions of Suns are assumed
to reside in the cores of most galaxies, and they play a key role in current models
of how galaxies have formed over the past billions of years."

Introduction to general relativity - Wikipedia
Galaxies formations can have their source "black holes".
Why?
1- "A black hole of one solar mass (M☉) has a temperature of only 60 nanokelvins
(60 billionths of a kelvin) Hawking radiation" / Wikipedia /
2- A black hole has a temperature within a few millionths
of a degree above absolute zero / Oxford. Dictionary./
3- "Stellar black holes are very cold: they have a temperature of nearly absolute zero –
which is zero Kelvin, or −273.15 degrees Celsius. Supermassive black holes are even colder."

Fact sheet: Black hole
One of these massive, mysterious objects lurks at the heart of our own galaxy.
The cold and infinite cosmic vacuum has the same temperature as black holes.
It means that so-called "black holes" are only parts of the infinite cosmic vacuum.
So-called "black hole" is other name of the cosmic vacuum.
And as was said " . . . they play a key role in current models of how galaxies have formed
over the past billions of years." as a process of quantum gravity going on for billions of years.
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