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arXiv · hep-th/0510052

Casimir energy and a cosmological bounce

Carlos A. R. Herdeiro·Marco Sampaio
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Abstract

We review different computation methods for the renormalised energy momentum tensor of a quantised scalar field in an Einstein Static Universe. For the extensively studied conformally coupled case we check their equivalence; for different couplings we discuss violation of different energy conditions. In particular, there is a family of masses and couplings which violate the weak and strong energy conditions but do not lead to spacelike propagation. Amongst these cases is that of a minimally coupled massless scalar field with no potential. We also point out a particular coupling for which a massless scalar field has vanishing renormalised energy momentum tensor. We discuss the backreaction problem and in particular the possibility that this Casimir energy could both source a short inflationary epoch and avoid the big bang singularity through a bounce.

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Carlos A. R. Herdeiro, Marco Sampaio. 2005-10-06. Casimir energy and a cosmological bounce. https://doi.org/10.1088/0264-9381%2F23%2F2%2F012

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