4 papers
When Tiny Halos Stir Spacetime: Gravitational Waves from Fifth-Force Mergers
Xinpeng Wang, Yifan Lu, Zachary S. C. Picker +2
Dark matter fermions interacting via attractive fifth forces mediated by a light mediator can form dark matter halos in the very early universe. We show that bound systems composed…
The Dual Primordial Black Hole Formation Scenario
Xinpeng Wang, Misao Sasaki, Ying-li Zhang
We report a novel mechanism where two families of primordial black holes (PBHs) may form at nearly the same comoving scales but at two different epochs. It is realized in two-stage…
Enhancement of primordial curvature perturbations in -corrected Starobinsky-Higgs inflation
Jinsu Kim, Xinpeng Wang, Ying-li Zhang +1
We provide a systematic study of the Starobinsky-Higgs inflation model in the presence of an additional cubic term of the Ricci scalar. We investigate, in particular, the effects o…
A complete analysis of inflation with piecewise quadratic potential
Xinpeng Wang, Xiao-Han Ma, Misao Sasaki
We conduct a thorough study of the comoving curvature perturbation in single-field inflation with two stages, represented by a piecewise quadratic potential, where bo…