https://doi.org/10.1140/epjc/s10052-017-4938-y
Regular Article - Theoretical Physics
The effective field theory of nonsingular cosmology: II
1
School of Physics, University of Chinese Academy of Sciences, Beijing, 100049, China
2
Institute of Astrophysics, Central China Normal University, Wuhan, 430079, China
3
Institute of Theoretical Physics, Chinese Academy of Sciences, P.O. Box 2735, Beijing, 100190, China
* e-mail: caiyong13@mails.ucas.ac.cn
Received:
9
May
2017
Accepted:
22
May
2017
Published online:
5
June
2017
Based on the effective field theory (EFT) of cosmological perturbations, we explicitly clarify the pathology in nonsingular cubic Galileon models and show how to cure it in EFT with new insights into this issue. With the least set of EFT operators that are capable to avoid instabilities in nonsingular cosmologies, we construct a nonsingular model dubbed the Genesis-inflation model, in which a slowly expanding phase (namely, Genesis) with increasing energy density is followed by slow-roll inflation. The spectrum of the primordial perturbation may be simulated numerically, which shows itself a large-scale cutoff, as the large-scale anomalies in CMB might be a hint for.
© The Author(s), 2017
