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arXiv · 0807.0954

Signature of short distance physics on inflation power spectrum and CMB anisotropy

Suratna Das·Subhendra Mohanty
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Abstract

The inflaton field responsible for inflation may not be a canonical fundamental scalar. It is possible that the inflaton is a composite of fermions or it may have a decay width. In these cases the standard procedure for calculating the power spectrum is not applicable and a new formalism needs to be developed to determine the effect of short range interactions of the inflaton on the power spectrum and the CMB anisotropy. We develop a general formalism for computing the power spectrum of curvature perturbations for such non-canonical cases by using the flat space Källén-Lehmann spectral function in curved quasi-de Sitter space assuming implicitly that the Bunch-Davis boundary conditions enforces the inflaton mode functions to be plane wave in the short wavelength limit and a complete set of mode functions exists in quasi-de Sitter space. It is observed that the inflaton with a decay width suppresses the power at large scale while a composite inflaton's power spectrum oscillates at large scales. These observations may be vindicated in the WMAP data and confirmed by future observations with PLANCK.

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Suratna Das, Subhendra Mohanty. 2009-08-24. Signature of short distance physics on inflation power spectrum and CMB anisotropy. https://doi.org/10.1088/1475-7516/2009/09/009

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