Power-counting and the Validity of the Classical Approximation During Inflation

2009/02/25 by C. P. Burgess, Hyun Min Lee, Michael Trott · 1 voice · 7 citations
Physics and Astronomy · #hep-ph #astro-ph.CO #gr-qc #hep-th

paper · pdf · doi:10.1088/1126-6708/2009/09/103

arxiv published 2009/02/25 · arxiv updated 2009/10/17

Abstract

We use the power-counting formalism of effective field theory to study the size of loop corrections in theories of slow-roll inflation, with the aim of more precisely identifying the limits of validity of the usual classical inflationary treatments. We keep our analysis as general as possible in order to systematically identify the most important corrections to the classical inflaton dynamics. Although most slow-roll models lie within the semiclassical domain, we find the consistency of the Higgs-Inflaton scenario to be more delicate due to the proximity between the Hubble scale during inflation and the upper bound allowed by unitarity on the new-physics scale associated with the breakdown of the semiclassical approximation within the effective theory. Similar remarks apply to curvature-squared inflationary models.

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Discussions

• 7/ For aficionados: the power-counting arguments for this made in arxiv.org/abs/0902.4465 apply even better in the late universe. It is the same reason why nonlinearities of GR cannot be neglected at [bsky, 4 points, 1 comments]

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