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arXiv · 1504.00894

Graviton Loop Corrections to Vacuum Polarization in de Sitter in a General Covariant Gauge

D. Glavan·S. P. Miao·Tomislav Prokopec·R. P. Woodard
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Abstract

We evaluate the one-graviton loop contribution to the vacuum polarization on de Sitter background in a 1-parameter family of exact, de Sitter invariant gauges. Our result is computed using dimensional regularization and fully renormalized with BPHZ counterterms, which must include a noninvariant owing to the time-ordered interactions. Because the graviton propagator engenders a physical breaking of de Sitter invariance two structure functions are needed to express the result. In addition to its relevance for the gauge issue this is the first time a covariant gauge graviton propagator has been used to compute a noncoincident loop. A number of identities are derived which should facilitate further graviton loop computations.

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D. Glavan, S. P. Miao, Tomislav Prokopec, R. P. Woodard. 2015-04-03. Graviton Loop Corrections to Vacuum Polarization in de Sitter in a General Covariant Gauge. https://doi.org/10.1088/0264-9381/32/19/195014

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