Causality and hyperbolicity of Lovelock theories

Harvey S. Reall, Norihiro Tanahashi, Benson Way

Research output: Contribution to journalArticle

46 Citations (Scopus)

Abstract

In Lovelock theories, gravity can travel faster or slower than light. The causal structure is determined by the characteristic hypersurfaces. We generalize a recent result of Izumi to prove that any Killing horizon is a characteristic hypersurface for all gravitational degrees of freedom of a Lovelock theory. Hence gravitational signals cannot escape from the region inside such a horizon. We investigate the hyperbolicity of Lovelock theories by determining the characteristic hypersurfaces for various backgrounds. First we consider Ricci flat type N spacetimes. We show that characteristic hypersurfaces are generically all non-null and that Lovelock theories are hyperbolic in any such spacetime. Next we consider static, maximally symmetric black hole solutions of Lovelock theories. Again, characteristic surfaces are generically non-null. For some small black holes, hyperbolicity is violated near the horizon. This implies that the stability of such black holes is not a well-posed problem.

Original languageEnglish
Article number205005
JournalClassical and Quantum Gravity
Volume31
Issue number20
DOIs
Publication statusPublished - Oct 21 2014
Externally publishedYes

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horizon
travel
escape
degrees of freedom
gravitation

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy (miscellaneous)

Cite this

Causality and hyperbolicity of Lovelock theories. / Reall, Harvey S.; Tanahashi, Norihiro; Way, Benson.

In: Classical and Quantum Gravity, Vol. 31, No. 20, 205005, 21.10.2014.

Research output: Contribution to journalArticle

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