3 papers
gr-qc2024
Towards a Complete Treatment of Scalar-induced Gravitational Waves with Early Matter Domination
Soubhik Kumar, Hanwen Tai, Lian-Tao Wang
Large curvature perturbations can source an observable amount of stochastic gravitational wave background (SGWB). We consider several scenarios where small-scale curvature perturba…
astro-ph.CO2023
Phase transition during inflation and the gravitational wave signal at pulsar timing arrays
Haipeng An, Boye Su, Hanwen Tai +2
The gravitational wave (GW) signal offers a promising window into the dynamics of the early universe. The recent results from the pulsar timing arrays (PTAs) could be the first gli…
astro-ph.CO2023
Gravitational Waves from Stochastic Scalar Fluctuations
Reza Ebadi, Soubhik Kumar, Amara McCune +2
We present a novel mechanism for gravitational wave generation in the early Universe. Light spectator scalar fields during inflation can acquire a blue-tilted power spectrum due to…