Can the curvaton paradigm accommodate a low inflation scale?

David H. Lyth

doi:10.1016/j.physletb.2003.11.019

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arXiv · hep-th/0308110

Can the curvaton paradigm accommodate a low inflation scale?

David H. Lyth

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Abstract

The cosmological curvature perturbation may be generated when some `curvaton' field, different from the inflaton, oscillates in a background of unperturbed radiation. In its simplest form the curvaton paradigm requires the Hubble parameter during inflation to be bigger than $10^7\GeV$, but this bound may be evaded if the curvaton field (or an associated tachyon) is strongly coupled to a field which acquires a large value at the end of inflation. As a result the curvaton paradigm might be useful in improving the viability of low-scale inflation models, in which the supersymmetry-breaking mechanism is the same as the one which operates in the vacuum.

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David H. Lyth. 2003-11-18. Can the curvaton paradigm accommodate a low inflation scale?. https://doi.org/10.1016/j.physletb.2003.11.019

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