155 citations · 255 across the 5 of their papers we have counts for
5 papers
Perturbative unitarity and NEC violation in genesis cosmology
Yong Cai, Ji Xu, Shuai Zhao +1
Explorations of the violation of null energy condition (NEC) in cosmology could enrich our understanding of the very early universe and the related gravity theories. Although a ful…
The Effective Field Theory of nonsingular cosmology
Yong Cai, Youping Wan, Hai-Guang Li +2
In this paper, we explore the nonsingular cosmology within the framework of the Effective Field Theory(EFT) of cosmological perturbations. Due to the recently proved no-go theorem,…
Chirality oscillation of primordial gravitational waves during inflation
Yong Cai, Yu-Tong Wang, Yun-Song Piao
We show that if the gravitational Chern-Simons term couples to a massive scalar field (), the primordial gravitational waves (GWs) will show itself the chirality oscillation,…
Oscillating modulation to B-mode polarization from varying propagating speed of primordial gravitational waves
Yong Cai, Yu-Tong Wang, Yun-Song Piao
In low-energy effective string theory and modified gravity theories, the propagating speed of primordial gravitational waves may deviate from unity. We find that the step-lik…
Pre-inflationary primordial perturbations
Yong Cai, Yu-Tong Wang, Yun-Song Piao
The large-scale power deficit in the cosmic microwave background fluctuations might be relevant with the physics of pre-inflation, a bounce, or a superinflationary phase preceding…