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arXiv · hep-th/0302050

A note on alpha-vacua and interacting field theory in de Sitter space

Kevin Goldstein·David A. Lowe
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Abstract

We set up a consistent renormalizable perturbation theory of a scalar field in a nontrivial alpha vacuum in de Sitter space. Although one representation of the effective action involves non-local interactions between anti-podal points, we show the theory leads to causal physics, and we prove a spectral theorem for the interacting two-point function. We construct the renormalized stress energy tensor and show this develops no imaginary part at leading order in the interactions, consistent with stability.

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Kevin Goldstein, David A. Lowe. 2003-07-22. A note on alpha-vacua and interacting field theory in de Sitter space. https://doi.org/10.1016/j.nuclphysb.2003.07.014

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