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Entropy of Constrained Gravitational Instanton

Wu Zhong Chao
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Abstract

The seeds for quantum creations of universes are constrained gravitational instantons. For all compact constrained instantons with U(1) isometry, the period $β$ of the group parameter $τ$ is identified as the reciprocal of the temperature. If $β$ remains a free parameter under the constraints, then the Euclidean action becomes the negative of the "entropy". As examples, we perform the calculations for the Taub-NUT and Taub-bolt-type models and study the quantum creation of the Taub-NUT universe.

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Wu Zhong Chao. 1998-12-17. Entropy of Constrained Gravitational Instanton. https://arxiv.org/abs/gr-qc/9812051

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