Decreasing entropy of dynamical black holes in critical gravity

Article

Decreasing entropy of dynamical black holes in critical gravity

Maeda, H.; Švarc, R.; Podolský, J.

J. High Energy Phys. 06, 118 (2018)

Abstract

Critical gravity is a quadratic curvature gravity in four dimensions which
is ghost-free around the AdS background. Constructing a Vaidya-type exact solution,
we show that the area of a black hole defined by a future outer trapping horizon can
shrink by injecting a charged null fluid with positive energy density, so that a black hole
is no more a one-way membrane even under the null energy condition. In addition, the
solution shows that the Wald-Kodama dynamical entropy of a black hole is negative and
can decrease. These properties expose the pathological aspects of critical gravity at the
non-perturbative level.

Institute authors

Supported by

GACR 17-01625S — Spacetimes and Fields in Einstein's Theory of Gravity and its Generalizations

BibTeX

@article{UTF660,
  author        = {Maeda, H. and Švarc, R. and Podolský, J.},
  title         = {{Decreasing entropy of dynamical black holes in critical gravity}},
  journal       = {J. High Energy Phys.},
  volume        = {06},
  pages         = {118},
  year          = {2018},
  doi           = {10.1007/JHEP06(2018)118},
}