5 papers
One-loop corrections to infrared GWs is forbidden by symmetries
Cheng-Jun Fang, Han-Wen Hu, Zong-Kuan Guo
Small-scale scalar perturbations amplified during inflation can induce primordial gravitational waves through tensor-scalar interactions. A long-standing controversial issue is whe…
Bispectrum of induced gravitational waves in the poltergeist mechanism
Han-Wen Hu, Cheng-Jun Fang, Zhen-Min Zeng +1
In the poltergeist mechanism the enhancement of induced gravitational waves (GWs) occurs due to a sudden transition from an early matter-dominated era to the radiation-dominated er…
Critical behavior and ultraviolet scaling of induced gravitational waves from an early matter-dominated era
Zhen-Min Zeng, Cheng-Jun Fang, Zong-Kuan Guo
Critical behavior and ultraviolet scaling of induced gravitational waves (GWs) from an early matter-dominated (eMD) era are studied in the context of primordial black hole evaporat…
Incorporating Backreaction in One-Loop Corrections in Ultra-Slow-Roll Inflation
Cheng-Jun Fang, Zhen-Hong Lyu, Chao Chen +1
We investigate the one-loop quantum correction to the power spectrum of primordial curvature perturbations in the ultra-slow-roll (USR) inflationary scenario, incorporating the bac…
Spectrum of third-order tensor perturbations induced by excited scalar fields
Cheng-Jun Fang, Zhi-Zhang Peng, Han-Wen Hu +1
We calculate for the first time the third-order spectrum of gravitational waves sourced by the amplified scalar field perturbations during inflation using the in-in formalism, and…