IAU01588
Presentation type requested: POSTER
BLACK HOLE VERSUS COSMOLOGICAL HORIZON ENTROPY
Charles H Lineweaver
Dept. of Astrophysics, University of New South Wales
The generalized second law of thermodynamics states that entropy always increases when all event horizons are attributed with an entropy proportional to their area. We test the generalized second law by investigating the change in entropy when dust, radiation and black holes cross a cosmological event horizon. We generalize for flat, open and closed Friedmann-Robertson-Walker universes by using numerical calculations to determine the cosmological horizon evolution. In most cases the loss of entropy from within the cosmological horizon is more than balanced by an increase in cosmological event horizon entropy, maintaining the validity of the generalized second law of thermodynamics. However, an intriguing set of open universe models show an apparent entropy decrease when black holes disappear over the cosmological event horizon. We anticipate that this apparent violation of the generalized second law is an artefact of our approximations and will disappear when solutions are available for black holes embedded in arbitrary backgrounds.
Davis Tamara M, Davies Paul C
IAU XXV General Assembly | IAU216 HOME PAGE | IAU216 Speaker Program | IAU216 Poster Program