Journal of High Energy Physics

, 2013:109 | Cite as

On loops in inflation II: IR effects in single clock inflation

  • Leonardo SenatoreEmail author
  • Matias Zaldarriaga
Open Access


In single clock models of inflation the coupling between modes of very different scales does not have any significant dynamical effect during inflation. It leads to interesting projection effects. Larger and smaller modes change the relation between the scale a mode of interest will appear in the post-inflationary universe and will also change the time of horizon crossing of that mode. We argue that there are no infrared projection effects in physical questions, that there are no effects from modes of longer wavelength than the one of interest at the time of reheating. These potential effects cancel when computing fluctuations as a function of physically measurable scales. Modes on scales smaller than the one of interest change the mapping between horizon crossing time and scale. The correction to the mapping computed in the absence of fluctuations is enhanced by a factor N e, the number of e-folds of inflation between horizon crossing and reheating. The new mapping is stochastic in nature but its variance is not enhanced by N e.


Cosmology of Theories beyond the SM Gauge Symmetry Space-Time Symmetries Renormalization Regularization and Renormalons 


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Copyright information

© SISSA 2013

Authors and Affiliations

  1. 1.Stanford Institute for Theoretical PhysicsStanford UniversityStanfordU.S.A
  2. 2.Kavli Institute for Particle Astrophysics and CosmologyStanford University and SLACMenlo ParkU.S.A
  3. 3.School of Natural Sciences, Institute for Advanced StudyPrincetonU.S.A

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