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arXiv · 0902.4283

Cosmological perturbations from an inhomogeneous phase transition

Tomohiro Matsuda
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Abstract

A mechanism for generating metric perturbations in inflationary models is considered. Long-wavelength inhomogeneities of light scalar fields in a decoupled sector may give rise to superhorizon fluctuations of couplings and masses in the low-energy effective action. Cosmological phase transitions may then occur that are not simultaneous in space, but occur with time lags in different Hubble patches that arise from the long-wavelength inhomogeneities. Here an interesting model in which cosmological perturbations may be created at the electroweak phase transition is considered. The results show that phase transitions may be a generic source of non-Gaussianity.

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Tomohiro Matsuda. 2009-04-22. Cosmological perturbations from an inhomogeneous phase transition. https://doi.org/10.1088/0264-9381%2F26%2F14%2F145011

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