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The first law for slowly evolving horizons

Ivan Booth·Stephen Fairhurst
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Abstract

We study the mechanics of Hayward's trapping horizons, taking isolated horizons as equilibrium states. Zeroth and second laws of dynamic horizon mechanics come from the isolated and trapping horizon formalisms respectively. We derive a dynamical first law by introducing a new perturbative formulation for dynamic horizons in which "slowly evolving" trapping horizons may be viewed as perturbatively non-isolated.

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Ivan Booth, Stephen Fairhurst. 2004-01-02. The first law for slowly evolving horizons. https://doi.org/10.1103/physrevlett.92.011102

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