395 citations · 8.2k across the 171 of their papers we have counts for
171 papers
Quasicrystalline Inflation: From the Cosmological Dipole to Primordial Diffraction
Jiro Soda
We propose quasicrystalline inflation. Six quasiperiodic phases decompose into three phonons and three phasons. It turns out that a coherent pure-phason displacement can generate a…
Stochastic tunneling in de Sitter spacetime
Taiga Miyachi, Jiro Soda, Junsei Tokuda
Tunneling processes in de Sitter spacetime are studied by using the stochastic approach. We exploit the Martin-Siggia-Rose-Janssen-de Dominicis (MSRJD) functional integral to obtai…
Hellings-Downs curve deformed by ultralight vector dark matter
Hidetoshi Omiya, Kimihiro Nomura, Jiro Soda
Pulsar timing arrays (PTAs) provide a way to detect gravitational waves (GWs) at nanohertz frequencies. To ensure the detection of GWs, observational data must exhibit the Hellings…
Circularly polarized gravitational waves in Chern-Simons gravity originated from an axion domain wall
Sugumi Kanno, Jiro Soda, Akira Taniguchi
We study a scattering problem of gravitational waves (GWs) by an axion domain wall in Chern-Simons (CS) gravity. We find that circular polarization of GWs is produced after passing…
Implications of multi-axion dark matter on structure formation
Chong-Bin Chen, Jiro Soda
Axions are candidates for dark matter in the universe.We develop an accurate Boltzmann code to calculate the linear growth of the plasma. As an interesting example, we investigate…
A peak in the power spectrum of primordial gravitational waves induced by primordial dark magnetic fields
Sugumi Kanno, Ann Mukuno, Jiro Soda +1
Dark gauge fields have been discussed as candidates for dark matter recently. If they existed, primordial dark magnetic fields during inflation would have existed. It is believed t…