46 citations · 127 across the 13 of their papers we have counts for
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Scalar-induced gravitational waves from a box-shaped curvature power spectrum
Zu-Cheng Chen, Lang Liu
We compute the stochastic background of gravitational waves (GWs) produced at second order in cosmological perturbation theory by a primordial curvature power spectrum that is flat…
Gauge Dependence of Gravitational Waves Induced by Primordial Isocurvature Fluctuations
Chen Yuan, Zu-Cheng Chen, Lang Liu
Primordial isocurvature perturbations, which can arise from various sources in the early Universe, have the potential to leave observable imprints on the gravitational-wave backgro…
Constraints on Inflation with Null Energy Condition Violation from Advanced LIGO and Advanced Virgo's First Three Observing Runs
Zu-Cheng Chen, Lang Liu
The null energy condition (NEC) is a cornerstone of general relativity, and its violation could leave observable imprints in the cosmic gravitational wave spectrum. Theoretical mod…
Detecting a Gravitational-Wave Background from Inflation with Null Energy Condition Violation: Prospects for Taiji
Zu-Cheng Chen, Lang Liu
The null energy condition (NEC) is a fundamental principle in general relativity, and its violation could leave discernible signatures in gravitational waves (GWs). A violation of…
Probing the speed of scalar-induced gravitational waves with pulsar timing arrays
Zu-Cheng Chen, Jun Li, Lang Liu +1
Recently, several regional pulsar timing array collaborations, including CPTA, EPTA, PPTA, and NANOGrav, have individually reported compelling evidence for a stochastic signal at n…