A Galileon Design of Slow Expansion
Cosmology and Nongalactic Astrophysics
2015-05-28 v2 General Relativity and Quantum Cosmology
High Energy Physics - Phenomenology
Abstract
We show a model of the slow expansion, in which the scale invariant spectrum of curvature perturbation is adiabatically induced by its increasing mode, by applying a generalized Galileon field. In this model, initially \epsilon << -1, which then is rapidly increasing, during this period the universe is slowly expanding. There is not the ghost instability, the perturbation theory is healthy. When \epsilon \sim -1, the slow expansion phase ends, and the available energy of field can be released and the universe reheats. This scenario might be a viable design of the early universe.
Keywords
Cite
@article{arxiv.1105.5713,
title = {A Galileon Design of Slow Expansion},
author = {Zhi-Guo Liu and Jun Zhang and Yun-Song Piao},
journal= {arXiv preprint arXiv:1105.5713},
year = {2015}
}
Comments
8 pages, 7 figures, minor changes and refs. added, published in PRD