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To: yefragetuwrabrumuy
'However, one a black hole is kicked out of a galaxy, it will likely “evaporate”.'

The rate of Hawking radiation emission (same as ideal black body radiation) is thought to be inversely proportionate to mass according to:

Therefore a million solar mass black hole would be observed at a temperature of about 0.00000000000006 deg K, and would be gaining net mass from both cosmic background radiation at 2.7 K, plus any starshine or other infalling mass source.

In the extremely distant future, if the expanding universe theory is correct, the cosmic background radiation might go low enough to cause a net mass loss...but we're talking trillions of years plus. Even then the rate of evaporation would be very slow.

Bear in mind that the radius of that million solar mass black hole's event horizon is about three million kilometers, so there's not really that much surface area to radiate from - that's only about four times larger than the Sun.

18 posted on 06/04/2012 1:47:48 PM PDT by PreciousLiberty (Pray for America!!!)
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To: PreciousLiberty

Question... Does the numerator on the right hand side have anything to do with Avogadro's number?

 

In the extremely distant future, if the expanding universe theory is correct,

Personally, I really hope heat death is not the ultimate fate of the universe. It would kind of make this whole enterprise a rather large waste of time.

24 posted on 06/04/2012 2:09:00 PM PDT by zeugma (Those of us who work for a living are outnumbered by those who vote for a living.)
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