Brett E. Taylor

Do semiclassical zero temperature black holes exist

The semiclassical Einstein equations are solved to first order in epsilon = Plancks over 2pi/M2 for the case of a Reissner-Nordström black hole perturbed by the vacuum stress energy of quantized free fields. Massless and massive fields of spin 0, 1/2, and 1 are considered. We show that in all physically realistic cases, macroscopic zero temperature black hole solutions do not exist. Any static zero temperature semiclassical black hole solutions must then be microscopic and isolated in the space of solutions; they do not join smoothly onto the classical extreme Reissner-Nordström solution as epsilon-->0.

Spinning Down a Black Hole with Scalar Fields

We study the evolution of a Kerr black hole emitting scalar radiation via the Hawking process. We show that the rate at which mass and angular momentum are lost by the black hole leads to a final evolutionary state with nonzero angular momentum, namely

Evaporation of a Kerr black hole by emission of scalar and higher spin particles

a/M \approx 0.555

Stress-energy of a quantized scalar field in static wormhole spacetimes

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Semiclassical charged black holes with a quantized massive scalar field

We study the evolution of an evaporating rotating black hole, described by the Kerr metric, which is emitting either solely massless scalar particles or a mixture of massless scalar and nonzero spin particles. Allowing the hole to radiate scalar particles increases the mass loss rate and decreases the angular momentum loss rate relative to a black hole which is radiating nonzero spin particles. The presence of scalar radiation can cause the evaporating hole to asymptotically approach a state which is described by a nonzero value of

Zero temperature black holes in semiclassical gravity

{a}_{*}\ensuremath{\equiv}a/M.

Zero and near-zero temperature black holes in semiclassical gravity

This is contrary to the conventional view of black hole evaporation, wherein all black holes spin down more rapidly than they lose mass. A hole emitting solely scalar radiation will approach a final asymptotic state described by

The `Ups' and `Downs' of a Spinning Black Hole

{a}_{*}\ensuremath{\simeq}0.555.

Reply: Anderson, Hiscock, and Taylor

A black hole that is emitting scalar particles and a canonical set of nonzero spin particles (3 species of neutrinos, a single photon species, and a single graviton species) will asymptotically approach a nonzero value of

Anderson, Hiscock, and Taylor Reply:

{a}_{*}