what is the composition of black hole?
is it a matter or antimatter or energy?
According to the well-known "no hair theorem", from the point of view of an external observer, a black hole has mass, charge and angular momentum and no other physical properties, so for example a black hole formed from antimatter would be indistinguishable from one formed from matter.
AFAIK, no one knows what a black hole (is) quantum loop theories try to circumvent (the) singularity, and as yet, all so AFAIK they have nothing to say about the galactic black hole.
Were can the stuff in a black hole go if it is not eternally locked up in space time?
Hawkings radiation, a so not tested conjecture.
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