Hawking Radiation, Tolman–Oppenheimer–Volkoff equation, and Black Hole Fireballs

The black hole fireball introduced in Ref. [1] describes the thermodynamic equilibrium of a self-gravitating perfect fluid studied using the Tolman–Oppenheimer–Volkoff equation. The analysis reveals that when there is enough energy in the container, a fireball can form that looks, from a distance, like a black hole emitting Hawking radiation. However, at the expected location of Schwarzschild radius there is no causal horizon. Instead, local temperature and density of the fluid rise sharply, forming a high-energy shell—a “firewall”—in the vicinity of the would-be horizon. A negative-mass singularity shielded by the shell of self-gravitating fluid resides at the center. This black hole fireball shows how back-reaction and self-gravity can modify the conventional view of a black-hole. I will focus on the equilibrium solutions associated with the fireball model [1,2], identifying the conditions under which these solutions correspond to stable or unstable equilibria.

[1] W. H. Zurek and D. N. Page, Phys. Rev. D 29, 628 (1984), also arXiv:1511.07051

[2] G. ’t Hooft, Nucl. Phys. Proc. Suppl. 68, 174–184 (1998).