Dark radiation as a probe for phase transition in the early universe
High Energy Physics - Phenomenology
2022-11-21 v2 Cosmology and Nongalactic Astrophysics
Abstract
The cosmological constant is not necessarily small in the early universe. If a scalar field obtains a vacuum expectation value after a phase transition (PT), a possibly large cosmological constant could present before PT. The early cosmological constant (ECC) and the PT process may be detectable from dark radiation (DR) today, such as in the cosmic axion background. We show that for a broad class of DR models, the DR density and spectrum are significantly modified by the presence of an ECC. From the density and the spectrum of the DR today, we can deduce the temperature and the strength of the PT.
Keywords
Cite
@article{arxiv.2204.03309,
title = {Dark radiation as a probe for phase transition in the early universe},
author = {Zihang Wang and Lijing Shao},
journal= {arXiv preprint arXiv:2204.03309},
year = {2022}
}
Comments
6 pages,4 figures