they say that if one black hole has two times more mass than the other black hole it's radius is two times bigger.(adsbygoogle = window.adsbygoogle || []).push({});

what if all the stars in the universe were to join to make one big big black hole how big would it be.

if a black hole with the mass of the sun is 3 km in radius and two times the mass of the sun is 6 km in radius then what would the black hole with all the stars in the universe be, what would it's radius be.

if there are 200 billion stars in a galaxy and there are 200 billion galaxy's in

the universe then there are 40,000,000,000,000,000,000,000 stars in the universe.

40,000,000,000,000,000,000,000 times 3 (because a black hole with a mass of a star the size of the sun is 3 km in radius) is 120,000,000,000,000,000,000,000.

so this black hole would be 120,000,000,000,000,000,000,000 km in radius

this is 20 billion light years in radius (because 1 light year is about 6,000,000,000,000 km)

now how is this possible if the universe is only 15 billion years old.

how can this black hole be bigger then the universe.???????????????????

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# Black hole and the universe

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