Suppression of the large scale curvature perturbation by interacting fluids

T. Multamaki; J. Sainio; I. Vilja

doi:10.1016/j.physletb.2007.03.008

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Suppression of the large scale curvature perturbation by interacting fluids

T. Multamaki·J. Sainio·I. Vilja

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Abstract

The large-scale dynamics of a two-fluid system with a time dependent interaction is studied analytically and numerically. We show how a rapid transition can significantly suppress the large-scale curvature perturbation and present approximative formulae for estimating the effect. By comparing to numerical results, we study the applicability of the approximation and find good agreement with exact calculations.

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T. Multamaki, J. Sainio, I. Vilja. 2007-01-24. Suppression of the large scale curvature perturbation by interacting fluids. https://doi.org/10.1016/j.physletb.2007.03.008

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