Leading log solution for inflationary Yukawa theory

Shun-Pei Miao, R. P. Woodard

Research output: Contribution to journalArticle

90 Citations (Scopus)

Abstract

We generalize Starobinskiǐ's stochastic technique to the theory of a massless, minimally coupled scalar interacting with a massless fermion in a locally de Sitter geometry. The scalar is an "active" field that can engender infrared logarithms. The fermion is a passive field that cannot cause infrared logarithms but which can carry them, and which can also induce new interactions between the active fields. The procedure for dealing with passive fields is to integrate them out, then stochastically simplify the resulting effective action following Starobinskiǐ. Because Yukawa theory is quadratic in the fermion this can be done explicitly using the classic solution of Candelas and Raine. We check the resulting stochastic formulation against an explicit two loop computation. We also derive a nonperturbative, leading log result for the stress tensor. Because the scalar effective potential induced by fermions is unbounded below, backreaction from this model might dynamically cancel an arbitrarily large cosmological constant.

Original languageEnglish
Article number044019
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Volume74
Issue number4
DOIs
Publication statusPublished - 2006 Aug 23

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fermions
scalars
logarithms
stress tensors
formulations
causes
geometry
interactions

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Physics and Astronomy (miscellaneous)

Cite this

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Leading log solution for inflationary Yukawa theory. / Miao, Shun-Pei; Woodard, R. P.

In: Physical Review D - Particles, Fields, Gravitation and Cosmology, Vol. 74, No. 4, 044019, 23.08.2006.

Research output: Contribution to journalArticle

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