4 papers
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…
Singular instantons with finite action
Misao Sasaki, Vicharit Yingcharoenrat, Ying-li Zhang
Recently, it was shown that in the absence of gravity there exist non--symmetric instanton solutions with finite action beyond Coleman's instantons. In this paper, focusing o…
Primordial Black Hole Formation from Power Spectrum with Finite-width
Shi Pi, Misao Sasaki, Volodymyr Takhistov +1
Primordial black holes (PBHs) can form from gravitational collapse of large overdensities in the early Universe, giving rise to rich phenomena in astrophysics and cosmology. We dev…
Beyond Coleman's Instantons
Misao Sasaki, Vicharit Yingcharoenrat, Ying-li Zhang
In the absence of gravity, Coleman's theorem states that the -symmetric instanton solution, which is regular at the origin and exponentially decays at infinity, gives the low…