405 citations · 5.4k across the 143 of their papers we have counts for
144 papers
Ellis-Bronnikov wormholes with NUT charge
Masato Nozawa, Tomohiro Harada, Keisuke Nakashi
We construct an exact NUT-charged generalization of the Ellis-Bronnikov wormhole in the Einstein-phantom-scalar system. The solution is stationary, asymptotically locally flat at b…
Spins of primordial black holes formed with a soft equation of state
Daiki Saito, Tomohiro Harada, Yasutaka Koga +1
We investigate the probability distribution of the spins of primordial black holes (PBHs) formed in the universe dominated by a perfect fluid with the linear equation of state $p=w…
Revisiting compaction functions for primordial black hole formation
Tomohiro Harada, Chul-Moon Yoo, Yasutaka Koga
Shibata and Sasaki [arXiv:gr-qc/9905064] introduced the so-called compaction function. Since then, it has been empirically established that the maximum value of this function (or i…
Hairy black holes in AdS with Robin boundary conditions
Tomohiro Harada, Takaaki Ishii, Takuya Katagiri +1
We study hairy black holes in Einstein-Maxwell-complex scalar theory in four-dimensional asymptotically global anti-de Sitter (AdS) spacetime when the Robin boundary conditions are…
Radiative gravastar with thermal spectrum; Sudden vacuum condensation without gravitational collapse
Ken-ichi Nakao, Kazumasa Okabayashi, Tomohiro Harada
The gravastar is an exotic compact object proposed as a final product of gravitational collapse of a massive object in order to resolve problems associated with black holes. It is…
Threshold of Primordial Black Hole Formation against Velocity Dispersion in Matter-Dominated Era
Tomohiro Harada, Kazunori Kohri, Misao Sasaki +2
We study the effects of velocity dispersion on the formation of primordial black holes~(PBHs) in a matter-dominated era. The velocity dispersion is generated through the nonlinear…