English

Stochastic Approach to Flat Direction during Inflation

High Energy Physics - Phenomenology 2015-06-05 v2 Cosmology and Nongalactic Astrophysics

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.

Keywords

Cite

@article{arxiv.1207.1165,
  title  = {Stochastic Approach to Flat Direction during Inflation},
  author = {Masahiro Kawasaki and Tomohiro Takesako},
  journal= {arXiv preprint arXiv:1207.1165},
  year   = {2015}
}

Comments

17 pages, 4 figures, v2: minor corrections made, published in JCAP

R2 v1 2026-06-21T21:30:49.038Z