Physics – High Energy Physics – High Energy Physics - Theory
Scientific paper
2006-08-24
JHEP 0701:045,2007
Physics
High Energy Physics
High Energy Physics - Theory
28 pages. v4: Published version with minor changes
Scientific paper
10.1088/1126-6708/2007/01/045
We analyze the Second Law of black hole mechanics and the generalization of the holographic bound for general theories of gravity. We argue that both the possibility of defining a holographic bound and the existence of a Second Law seem to imply each other via the existence of a certain "c-function" (i.e. a never-decreasing function along outgoing null geodesic flow). We are able to define such a "c-function", that we call \tilde{C}, for general theories of gravity. It has the nontrivial property of being well defined on general spacelike surfaces, rather than just on a spatial cross-section of a black hole horizon. We argue that \tilde{C} is a suitable generalization of the notion of "area" in any extension of the holographic bound for general theories of gravity. Such a function is provided by an algorithm which is similar (although not identical) to that used by Iyer and Wald to define the entropy of a dynamical black hole. In a class of higher curvature gravity theories that we analyze in detail, we are able to prove the monotonicity of \tilde{C} if several physical requirements are satisfied. Apart from the usual ones, these include the cancellation of ghosts in the spectrum of the gravitational Lagrangian. Finally, we point out that our \tilde{C}-function, when evaluated on a black hole horizon, constitutes by itself an alternative candidate for defining the entropy of a dynamical black hole.
Cremades Daniel
Lozano-Tellechea Ernesto
No associations
LandOfFree
Holography, The Second Law and a C-Function in Higher Curvature Gravity does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Holography, The Second Law and a C-Function in Higher Curvature Gravity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Holography, The Second Law and a C-Function in Higher Curvature Gravity will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-339304