401 citations · 829 across the 23 of their papers we have counts for
5 papers · 1 filter
Is there an effect of a nontrivial during inflation?
Yong Cai, Yu-Tong Wang, Yun-Song Piao
Recently, we have shown that the propagation speed of the primordial gravitational waves (GWs) might be nontrivially varying during inflation, which could induce local oscill…
Oscillation in power spectrum of primordial gravitational wave as a signature of higher-order stringy corrections
Yong Cai, Yu-Tong Wang, Yun-Song Piao
In low-energy effective string theory, corrections involve the coupling of the dilaton field to Gauss-Bonnet term. We assume that the dilaton potential is fine tuned so that t…
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…
G-Bounce Inflation: Towards Nonsingular Inflation Cosmology with Galileon Field
Taotao Qiu, Yu-Tong Wang
We study a nonsingular bounce inflation model, which can drive the early universe from a contracting phase, bounce into an ordinary inflationary phase, followed by the reheating pr…
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…