Hypothetical Object
White Hole
A theoretical time-reverse of a black hole.
A solution to Einstein's equations describing a region of spacetime that cannot be entered from outside, the time-reverse of a black hole. No observational evidence.
Overview
A solution to Einstein's equations describing a region of spacetime that cannot be entered from outside, the time-reverse of a black hole. No observational evidence.
See also
Dark Matter Spike
A density enhancement of dark matter around a black hole.
Fuzzball
A string-theory replacement for a black hole.
Planck Star
A bouncing quantum-gravity remnant inside a black hole.
Black Dwarf
A theoretical cold white-dwarf remnant.
Gravastar
A black-hole alternative made of exotic vacuum.
Wormhole (Einstein–Rosen Bridge)
A theoretical tunnel through spacetime.