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Adiabatic And Entropy Perturations In Inflationary Models Based On Non-linear Sigma Model

N. A. Koshelev
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Abstract

The scalar perturbations in inflationary models, based on a two-component diagonal non-linear sigma model, are considered. For inhomogeneities generated at an inflationary stage, the law of motion of the comoving curvature ${\cal R}$ is obtained (without using the slow roll approximations). A formal expressions for the power spectrum and its spectral index are obtained, which are valid and after the slow-roll stage. As an example, an inflationary model with a massive scalar field and quadratic curvature corrections is studied numerically.

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N. A. Koshelev. 2005-01-27. Adiabatic And Entropy Perturations In Inflationary Models Based On Non-linear Sigma Model. https://arxiv.org/abs/astro-ph/0501600

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