# Question about a "general" definition for a black hole and his validity outer General Relativity

Consider the following definition:

A Black Hole in an asymptotically flat spacetime $$\mathfrak{M} \equiv (\mathcal{M}, \mathrm{\textbf{g}})$$ is the set of events that do not belong to the causal past of the future null infinity $$J^{-}(\mathfrak{I}^{+})$$, namely: $$\mathfrak{B} = \mathfrak{M}-J^{-}(\mathfrak{I}^{+})\neq \varnothing$$

The boundary of $$\mathfrak{B}$$ is called event horizon.

My question is: this definition is a general one, i.e., in the sense that this definition is both valid for Astrophysical Black Holes (the soluitons from General Relativity e.g. Schwarzschild,Kerr,Reissner-Nordström,Kerr-Newman solutions) and "quantum black holes"?

• What are quantum black holes? Apr 8, 2019 at 20:55