155 citations · 1.2k across the 32 of their papers we have counts for
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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,…
Towards the bounce inflationary gravitational wave
Hai-Guang Li, Yong Cai, Yun-Song Piao
In bounce inflation scenario, the inflation is singularity-free, while the advantages of inflation are reserved. We analytically calculate the power spectrum of its primordial grav…
Propagating speed of primordial gravitational waves and inflation
Yong Cai, Yu-Tong Wang, Yun-Song Piao
We show that if the propagating speed of gravitational waves (GWs) gradually diminishes during inflation, the power spectrum of primordial GWs will be strongly blue, while that of…
The slow expansion with nonminimal derivative coupling and its conformal dual
Yong Cai, Yun-Song Piao
We show that the primordial gravitational wave with scale-invariant spectrum might emerge from a nearly Minkowski space, in which the gravity is asymptotic-past free. We illustrate…