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On the Vacuum Energy in Expanding Space-Times

Achim Kempf
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Abstract

If there is a shortest length in nature, for example at the Planck scale of 10^-35m, then the cosmic expansion should continually create new comoving modes. A priori, each of the new modes comes with its own vacuum energy, which could contribute to the cosmological constant. I discuss possible mathematical models for a shortest length and an explicit model for a corresponding mode-generating mechanism.

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Achim Kempf. 2002-10-23. On the Vacuum Energy in Expanding Space-Times. https://arxiv.org/abs/gr-qc/0210077

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