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arXiv · 1507.01054

Black hole entropy and Lorentz-diffeomorphism Noether charge

Ted Jacobson·Arif Mohd
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Abstract

We show that, in the first or second order orthonormal frame formalism, black hole entropy is the horizon Noether charge for a combination of diffeomorphism and local Lorentz symmetry involving the Lie derivative of the frame. The Noether charge for diffeomorphisms alone is unsuitable, since a regular frame cannot be invariant under the flow of the Killing field at the bifurcation surface. We apply this formalism to Lagrangians polynomial in wedge products of the frame field 1-form and curvature 2-form, including general relativity, Lovelock gravity, and "topological" terms in four dimensions.

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Ted Jacobson, Arif Mohd. 2015-12-15. Black hole entropy and Lorentz-diffeomorphism Noether charge. https://doi.org/10.1103/physrevd.92.124010

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