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arXiv · 2503.16138

The entropy of dynamical de Sitter horizons

Jinan Zhao
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Abstract

Recently Hollands, Wald and Zhang proposed a new formula for the entropy of a dynamical black hole. We lift this construction to the dynamical cosmological event horizon of an asymptotically de Sitter spacetime. By introducing a nontrivial correction term in the formula for the entropy, we generalize Gibbons and Hawking's "first law of event horizons" to non-stationary eras. We also develop the non-stationary physical process first law between two arbitrary horizon cross-sections for the cosmological event horizon.

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Jinan Zhao. 2025-07-02. The entropy of dynamical de Sitter horizons. https://doi.org/10.1140/epjc%2Fs10052-025-14471-9

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