1993/09/30 by Sean A. Hayward, Tetsuya Shiromizu, Ken-ichi Nakao +1 · 6 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Noncommutative and Quantum Gravity Theories #gr-qc
paper · pdf · doi:10.1103/physrevd.49.5080
published as Phys.Rev. D49 (1994) 5080-5085 · 10 pages
openalex publication_date 1994/05/15 · arxiv created 1994/05/25 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
In a space-time with cosmological constant \ensuremathΛ>0 and matter satisfying the dominant energy condition, the area of a black or white hole cannot exceed \frac4\ensuremathπ\ensuremathΛ. This applies to event horizons where defined, i.e., in an asymptotically de Sitter space-time, and to outer trapping horizons (cf. apparent horizons) in any space-time. The bound is attained if and only if the horizon is identical to that of the degenerate "Schwarzschild-de Sitter" solution. This yields a topological restriction on the event horizon, namely that components whose total area exceeds \frac4\ensuremathπ\ensuremathΛ cannot merge. We discuss the conjectured isoperimetric inequality and implications for the cosmic censorship conjecture.