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A stable static Universe?

Carlos Barcelo·Grigory Volovik
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Abstract

Starting from the assumption that general relativity might be an emergent phenomenon showing up at low-energies from an underlying microscopic structure, we re-analyze the stability of a static closed Universe filled with radiation. In this scenario, it is sensible to consider the effective general-relativistic configuration as in a thermal contact with an "environment" (the role of environment can be played, for example, by the higher-dimensional bulk or by the trans-Planckian degrees of freedom). We calculate the free energy at a fixed temperature of this radiation-filled static configuration. Then, by looking at the free energy we show that the static Einstein configuration is stable under the stated condition.

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Carlos Barcelo, Grigory Volovik. 2004-07-28. A stable static Universe?. https://doi.org/10.1134/1.1813673

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