165 citations · 2.5k across the 85 of their papers we have counts for
9 papers · 1 filter
Tunneling wave function of the universe II: the backreaction problem
Alexander Vilenkin, Masaki Yamada
The tunneling wave function of the universe is calculated exactly for a de Sitter minisuperspace model with a massless conformally coupled scalar field, both by solving the Wheeler…
Self-interacting dark matter with a vector mediator: kinetic mixing with U(1) gauge boson
Ayuki Kamada, Masaki Yamada, Tsutomu T. Yanagida
A spontaneously broken hidden U(1) gauge symmetry can explain both the dark matter stability and the observed relic abundance. In this framework, the light gauge boson can medi…
Tunneling wave function of the universe
Alexander Vilenkin, Masaki Yamada
The tunneling wave function of the universe is investigated in a minisuperspace framework of a de Sitter universe with a quantum scalar field, treated as a perturbation. We conside…
Isocurvature Perturbations of Dark Energy and Dark Matter from the Swampland Conjecture
Hiroki Matsui, Fuminobu Takahashi, Masaki Yamada
We point out that the recently proposed Swampland conjecture on the potential gradient can lead to isocurvature perturbations of dark energy, if the quintessence field acquires lar…
Compact objects as the catalysts for vacuum decays
Naritaka Oshita, Masaki Yamada, Masahide Yamaguchi
We discuss vacuum decays catalyzed by spherical and horizonless objects and show that an ultra compact object could catalyze a vacuum decay around it within the cosmological time.…
Classical Nonrelativistic Effective Field Theory and the Role of Gravitational Interactions
Joshua Eby, Kyohei Mukaida, Masahiro Takimoto +2
Coherent oscillation of axions or axion-like particles may give rise to long-lived clumps, called axion stars, because of the attractive gravitational force or its self-interaction…
Unified Origin of Axion and Monopole Dark Matter, and Solution to the Domain-wall Problem
Ryosuke Sato, Fuminobu Takahashi, Masaki Yamada
We propose a scenario where the spontaneous breakdown of the Peccei-Quinn symmetry leads to monopole production. Both the axion and the monopole contribute to dark matter, and the…
CMB spectral distortions from black holes formed by vacuum bubbles
Heling Deng, Alexander Vilenkin, Masaki Yamada
Vacuum bubbles may nucleate and expand during the cosmic inflation. When inflation ends, the bubbles run into the ambient plasma, producing strong shocks followed by underdensity w…
Primordial Black Holes from Polynomial Potentials in Single Field Inflation
Mark P. Hertzberg, Masaki Yamada
Within canonical single field inflation models, we provide a method to reverse engineer and reconstruct the inflaton potential from a given power spectrum. This is not only a usefu…