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Perturbative analysis of multiple-field cosmological inflation

Joydev Lahiri·Gautam Bhattacharya
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Abstract

We develop a general formalism for analyzing linear perturbations in multiple-field cosmological inflation based on the gauge-ready approach. Our inflationary model consists of an arbitrary number of scalar fields with non-minimal kinetic terms. We solve the equations for scalar- and tensor-type perturbations during inflation to the first order in slow-roll, and then obtain the super-horizon solutions for adiabatic and isocurvature perturbations after inflation. Analytic expressions for power-spectra and spectral indices arising from multiple-field inflation are presented.

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Joydev Lahiri, Gautam Bhattacharya. 2006-01-12. Perturbative analysis of multiple-field cosmological inflation. https://doi.org/10.1016/j.aop.2005.11.006

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