Emergent Universe and Genesis from the DHOST Cosmology
General Relativity and Quantum Cosmology
2021-01-26 v1 Cosmology and Nongalactic Astrophysics
High Energy Physics - Phenomenology
High Energy Physics - Theory
Abstract
In this article, we present an emergent universe scenario that can be derived from DHOST cosmology. The universe starts asymptotically Minkowski in the far past just like the regular Galileon Genesis, but evolves to a radiation dominated period at the late stage, and therefore, the universe has a graceful exit which is absent in the regular Galileon Genesis. We analyze the behavior of cosmological perturbations and show that both the scalar and tensor modes are free from the gradient instability problem. We further analyze the primordial scalar spectrum generated in various situations and discuss whether a scale invariance can be achieved.
Keywords
Cite
@article{arxiv.2009.10351,
title = {Emergent Universe and Genesis from the DHOST Cosmology},
author = {Amara Ilyas and Mian Zhu and Yunlong Zheng and Yi-Fu Cai},
journal= {arXiv preprint arXiv:2009.10351},
year = {2021}
}
Comments
12 pages, 6 main figures, comments are welcome