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arXiv · 1301.2501

Exact noise kernel for quantum fields in static de Sitter and conformally-flat spacetimes

Jason D. Bates·Hing-Tong Cho·Paul R. Anderson·B. L. Hu
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Abstract

We compute exact expressions of the noise kernel, defined as the expectation value of the symmetrized connected stress energy bitensor, for conformally-invariant scalar fields with respect to the conformal vacuum, valid for an arbitrary separation (timelike, spacelike and null) of points in a class of conformally-flat spacetimes. We derive explicit expressions for the noise kernel evaluated in the static de Sitter coordinates with respect to the Gibbons-Hawking vacuum and analyze the behavior of the noise kernel in the region near the cosmological horizon. We develop a quasi-local expansion near the cosmological horizon and compare it with the exact results. This gives insight into the likely range of validity of the quasi-local approximation expressions for the noise kernel for the conformally invariant scalar field in Schwarzschild spacetime which are given in PHYSICAL REVIEW D{\bf 85}, 044037 (2012).

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Jason D. Bates, Hing-Tong Cho, Paul R. Anderson, B. L. Hu. 2013-01-11. Exact noise kernel for quantum fields in static de Sitter and conformally-flat spacetimes. https://arxiv.org/abs/1301.2501

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