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Author Topic: Size of black holes and how they're measured  (Read 4262 times)

gbrak30

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Size of black holes and how they're measured
« on: January 04, 2016, 06:56:02 AM »
So if black holes are infinitely small, how can they have a diameter?  I prefer asking people rather than google, since this can be more of a philosophical question ;)
Well, I have never seen a diameter but mass i have seen, but still, how do you measure the size/mass of something you cannot observe directly and that is theoretically infinitely small?
« Last Edit: January 04, 2016, 07:01:17 AM by gbrak30 »

codefantastic

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Re: Size of black holes and how they're measured
« Reply #1 on: January 04, 2016, 06:58:06 AM »
the black hole itself isn't infantly small, the singularity at the center is.

Darvince

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Re: Size of black holes and how they're measured
« Reply #2 on: January 05, 2016, 02:43:51 PM »
the diameter of a black hole is defined as the diameter of its event horizon as the singularity itself has no size as far as we know

vh

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Re: Size of black holes and how they're measured
« Reply #3 on: January 05, 2016, 03:47:59 PM »
to add, mass is measured by velocites of orbiting bodies, and the event horizon can be computed from mass

fredetuc

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Re: Size of black holes and how they're measured
« Reply #4 on: March 28, 2016, 11:00:31 AM »
Well lets say this u can make a black hole out of anything as long as you shrink it down to microscopic size but keep the same mass. Don't quote me on this but i'm 89% sure.