2013/02/11 by Bethan Cropp, Stefano Liberati, Matt Visser · 2 citations
Physics and Astronomy · #gr-qc #hep-th
paper · pdf · doi:10.1088/0264-9381/30/12/125001
published as Classical and Quantum Gravity 30 (2013) 125001 · 29 pages, 1 table
arxiv created 2013/02/11 · arxiv updated 2013/06/18
There are many logically and computationally distinct characterizations of the surface gravity of a horizon, just as there are many logically rather distinct notions of horizon. Fortunately, in standard general relativity, for stationary horizons, most of these characterizations are degenerate. However, in modified gravity, or in analogue spacetimes, horizons may be non-Killing or even non-null, and hence these degeneracies can be lifted. We present a brief overview of the key issues, specifically focusing on horizons in analogue spacetimes and universal horizons in modified gravity.