761 citations · 2.4k across the 63 of their papers we have counts for
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How Do Nonlinear Voids Affect Light Propagation ?
Norimasa Sugiura, Ken-ichi Nakao, Daisuke Ida +2
Propagation of light in a clumpy universe is examined. As an inhomogeneous matter distribution, we take a spherical void surrounded by a dust shell where the ``lost mass'' in the v…
Causal Structure of an Inflating Magnetic Monopole
Nobuyuki Sakai, Ken-ichi Nakao, Tomohiro Harada
We clarify the causal structure of an inflating magnetic monopole. The spacetime diagram shows explicitly that this model is free from ``graceful exit'' problem, while the monopole…
Peculiar Velocities of Nonlinear Structure: Voids in McVittie Spacetime
Nobuyuki Sakai, Paul Haines
As a study of peculiar velocities of nonlinear structure, we analyze the model of a relativistic thin-shell void in the expanding universe. (1) Adopting McVittie (MV) spacetime as…
Gauged Monopole-Bubble
Yoonbai Kim, Seung Joo Lee, Kei-ichi Maeda +1
The decay of a metastable false vacuum by bubble nucleation is studied in the high temperature limit of the gauge theory in which an SO(3) gauge symmetry is spontaneously broken to…
Topological inflation induced by a non-minimally coupled massive scalar field
Nobuyuki Sakai, Jun'ichi Yokoyama
We reanalyze cosmology of a non-minimally coupled massive scalar field which was originally discussed by Futamase and Maeda in the context of chaotic inflation scenario. We find a…