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Back-reaction of Quantum fields in an Einstein Universe

M. B. Altaie
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Abstract

We study the back-reaction effects of the finite-temperature scalar field and the photon field in the background of an Einstein universe. In each case we find a relation between the temperature of the universe and its radius. These relations exhibit a minimum radius below which no self-consistent solution for the Einstein field equation can be found. A maximum temperature marks the transition from the vacuum dominated era to the radiation dominated era. An interpretation to this behavior in terms of Bose-Einstein condensation in the case of the scalar field is given.

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M. B. Altaie. 2001-04-30. Back-reaction of Quantum fields in an Einstein Universe. https://doi.org/10.1103/physrevd.65.044028

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