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Enhancement of superhorizon scale inflationary curvature perturbations

Samuel M Leach·Misao Sasaki·David Wands·Andrew R Liddle
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Abstract

We show that there exists a simple mechanism which can enhance the amplitude of curvature perturbations on superhorizon scales during inflation, relative to their amplitude at horizon crossing. The enhancement may occur even in a single-field inflaton model, and occurs if the quantity $a\dotϕ/H$ becomes sufficiently small, as compared to its value at horizon crossing, for some time interval during inflation. We give a criterion for this enhancement in general single-field inflation models.

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Samuel M Leach, Misao Sasaki, David Wands, Andrew R Liddle. 2001-02-21. Enhancement of superhorizon scale inflationary curvature perturbations. https://doi.org/10.1103/physrevd.64.023512

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