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arXiv · 0905.0405

Loop Corrections to Cosmological Perturbations in Multi-field Inflationary Models

Xian Gao·Fanrong Xu
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Abstract

We investigate one-loop quantum corrections to the power spectrum of adiabatic perturbation from entropy modes/adiabatic mode cross-interactions in multiple DBI inflationary models. We find that due to the non-canonical kinetic term in DBI models, the loop corrections are enhanced by slow-varying parameter $ε$ and small sound speed $c_s$. Thus, in general the loop-corrections in multi-DBI models can be large. Moreover, we find that the loop-corrections from adiabatic/entropy cross-interaction vertices are IR finite.

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BibTeXRIS

Xian Gao, Fanrong Xu. 2009-07-14. Loop Corrections to Cosmological Perturbations in Multi-field Inflationary Models. https://doi.org/10.1088/1475-7516/2009/07/042

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