Upper bound on the energies of the emitted Hawking quanta

Abstract

Using Thorne's hoop conjecture, it is argued that the energies of the Hawking quanta emitted from canonical Schwarzschild black holes are bounded from above by the simple quantum relation ${\cal E}<{\cal E}_{\text{max}}={\hbar^{2/3}}/M^{1/3}$. In particular, it is shown that, due to non-linear (self-gravity) effects of the tunneling quanta, higher energy field modes are re-absorbed (rather than escape to infinity) by the black hole.