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Sizes of black holes 
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#1
Dec1212, 02:27 PM

P: 51

If a black hole is a stellar structure that has collapsed on itself to a singularity does that mean it has no size? But is so defined by its mass and schwarzschild radius?
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#2
Dec1212, 03:24 PM

Mentor
P: 11,844

The black hole has a size defined by the event horizon. The actual volume and such is a bit more complicated to determine due to spacetime curvature I believe. A singularity, IF it exists at all, would have no size.



#3
Dec1212, 07:13 PM

Sci Advisor
P: 6,059

Current physical theory is unable to accurately describe what is going on inside the event horizon of a black hole. Quantum theory and general relativity don't mesh, and they both come into play.



#4
Jan313, 12:34 PM

P: 2

Sizes of black holes
The thing to realise is that the term 'black hole' doesn't mean: 'the bit at the center where all of the mass is concentrated, that may or may not be a singularity'.
'black hole' refers to the whole volume inside the event horizon, which clearly can have a radius, surface area and volume. my understanding is that nonrotating black holes are perfect spheres with a radii equal to their Schwarzchild radius, and that rotating black holes are distorted into oblate spheroids, as are most rotating stellar objects. 


#5
Jan413, 02:17 PM

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#6
Jan613, 09:47 AM

P: 27

How can it be one dimensional with a circumference and a radius? does that make it 2 dimensional?



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