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arXiv · 1207.1165

Stochastic Approach to Flat Direction during Inflation

Masahiro Kawasaki·Tomohiro Takesako
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Abstract

We revisit the time evolution of a flat and non-flat direction system during inflation. In order to take into account quantum noises in the analysis, we base on stochastic formalism and solve coupled Langevin equations numerically. We focus on a class of models in which tree-level Hubble-induced mass is not generated. Although the non-flat directions can block the growth of the flat direction's variance in principle, the blocking effects are suppressed by the effective masses of the non-flat directions. We find that the fate of the flat direction during inflation is determined by one-loop radiative corrections and non-renormalizable terms as usually considered, if we remove the zero-point fluctuation from the noise terms.

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Masahiro Kawasaki, Tomohiro Takesako. 2012-08-29. Stochastic Approach to Flat Direction during Inflation. https://doi.org/10.1088/1475-7516%2F2012%2F08%2F031

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