4 papers
Observable Gravitational Wave Strain at Second Order
Guillem Domènech, Shi Pi, Ao Wang
There is currently no rigorous definition of gravitational wave strain at second order in cosmological perturbation theory. The usual association of gravitational waves with transv…
A Unified Origin of Primordial Black Hole Dark Matter and Nanohertz Gravitational Waves
Guillem Domènech, Shi Pi, Ao Wang
Recent high-cadence observations by Subaru-HSC have identified a population of ultrashort-timescale microlensing events, providing a compelling window for planet-mass primordial bl…
Constraining the Primordial Black Hole Abundance with Space-Based Detectors
Wencong Hong, Shi Pi, Ao Wang +1
Overdense regions can collapse into primordial black holes (PBHs) in the early universe, which are a compelling candidate for dark matter. Current constraints leave the asteroid-ma…
Axion-like Universal Gravitational Wave Interpretation of Pulsar Timing Array Data
Kaloian D. Lozanov, Shi Pi, Misao Sasaki +2
Formation of cosmological solitons is generically accompanied by production of gravitational waves (GWs), with a universal GW background expected at frequency scales below that of…