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Entropy of Spacelike Two-Surfaces of Spacetime

J. Makela·A. Peltola
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Abstract

We argue that every finite piecewise smooth spacelike two-surface of spacetime possesses an entropy which is, in natural units, one quarter of its area. However, the thermodynamical properties of a two-surface become apparent only to the observers having that two-surface as a horizon. Consequences of this result are discussed.

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J. Makela, A. Peltola. 2004-06-08. Entropy of Spacelike Two-Surfaces of Spacetime. https://arxiv.org/abs/gr-qc/0406032

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