i read that the escape velocity from black hole is greater then C, my question is: is that true for all black holes, or we could have some black holes which have smaller escape velocity than C, there's the equation v=sqrt(2MG/R) which implies that M/R>c^2/2G, but does the star before it becomes a black hole cannot change its mass (i think that infact before it becomes a black hole, it shrinks into neutron star which is radius is much smaller. but does its mass stays as it was?).(adsbygoogle = window.adsbygoogle || []).push({});

p.s

1.when a black hole "consumes" (if this term is correct) mass from its surrondings, does it not expand? and if it does does its event horizon increase as well?

2. i heard that perhaps black holes' end in vaporization, how is this idea is being conveyed?

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# Escape velocity of a body from a black hole.

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