Cosmologically safe QCD axion as a present from extra dimension
High Energy Physics - Phenomenology
2015-09-30 v1 Cosmology and Nongalactic Astrophysics
Abstract
We propose a QCD axion model where the origin of PQ symmetry and suppression of axion isocurvature perturbations are explained by introducing an extra dimension. Each extra quark-antiquark pair lives on branes separately to suppress PQ breaking operators. The size of the extra dimension changes after inflation due to an interaction between inflaton and a bulk scalar field, which implies that the PQ symmetry can be drastically broken during inflation to suppress undesirable axion isocurvature fluctuations.
Cite
@article{arxiv.1506.05214,
title = {Cosmologically safe QCD axion as a present from extra dimension},
author = {Masahiro Kawasaki and Masaki Yamada and Tsutomu T. Yanagida},
journal= {arXiv preprint arXiv:1506.05214},
year = {2015}
}
Comments
6 pages