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The Fermion Self-Energy during Inflation

Shun-Pei Miao·R. P. Woodard
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Abstract

We compute the one loop fermion self-energy for massless Dirac + Einstein in the presence of a locally de Sitter background. We employ dimensional regularization and obtain a fully renormalized result by absorbing all divergences with BPHZ counterterms. An interesting technical aspect of this computation is the need for a noninvariant counterterm owing to the breaking of de Sitter invariance by our gauge condition. Our result can be used in the quantum-corrected Dirac equation to search for inflation-enhanced quantum effects from gravitons, analogous to those which have been found for massless, minimally coupled scalars.

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Shun-Pei Miao, R. P. Woodard. 2006-02-06. The Fermion Self-Energy during Inflation. https://doi.org/10.1088/0264-9381%2F23%2F5%2F016

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