83 citations · 400 across the 18 of their papers we have counts for
9 papers · 1 filter
Abundance of cosmic voids in EFT of dark energy
Toshiki Takadera, Shin'ichi Hirano, Tsutomu Kobayashi
Cosmic voids in the large-scale structure are among the useful probes for testing gravity on cosmological scales. In this paper, we investigate the evolution of voids in the Hornde…
Stochastic gravitational wave background anisotropies from inflation with non-Bunch-Davies states
Shingo Akama, Shin'ichi Hirano, Shuichiro Yokoyama
It is known that stochastic gravitational wave backgrounds (SGWBs) have anisotropies generated by squeezed-type tensor non-Gaussianities originating from scalar-tensor-tensor (STT)…
First test of the consistency relation for the large-scale structure using the anisotropic three-point correlation function of BOSS DR12 galaxies (An explanatory video is available at https://youtu.be/Zi36ooLPhss.)
Naonori S. Sugiyama, Daisuke Yamauchi, Tsutomu Kobayashi +6
We present, for the first time, an observational test of the consistency relation for the large-scale structure (LSS) of the Universe through a joint analysis of the anisotropic tw…
New constraints on cosmological modified gravity theories from anisotropic three-point correlation functions of BOSS DR12 galaxies
Naonori S. Sugiyama, Daisuke Yamauchi, Tsutomu Kobayashi +6
We report a new test of modified gravity theories using the large-scale structure of the Universe. This paper is the first attempt to (1) apply a joint analysis of the anisotropic…
Cosmological gravity probes: connecting recent theoretical developments to forthcoming observations
Shun Arai, Katsuki Aoki, Yuji Chinone +20
Since the discovery of the accelerated expansion of the present Universe, significant theoretical developments have been made in the area of modified gravity. In the meantime, cosm…
Abundance of Primordial Black Holes in Peak Theory for an Arbitrary Power Spectrum
Chul-Moon Yoo, Tomohiro Harada, Shin'ichi Hirano +1
We modify the procedure to estimate PBH abundance proposed in arXiv:1805.03946 so that it can be applied to a broad power spectrum such as the scale-invariant flat power spectrum.…
Constraining DHOST theories with linear growth of matter density fluctuations
Shin'ichi Hirano, Tsutomu Kobayashi, Daisuke Yamauchi +1
We investigate the potential of cosmological observations, such as galaxy surveys, for constraining degenerate higher-order scalar-tensor (DHOST) theories, focusing in particular o…
Matter bispectrum beyond Horndeski
Shin'ichi Hirano, Tsutomu Kobayashi, Hiroyuki Tashiro +1
The Horndeski scalar-tensor theory and its recent extensions allow nonlinear derivative interactions of the scalar degree of freedom. We study the matter bispectrum of large scale…
Ultra slow-roll G-inflation
Shin'ichi Hirano, Tsutomu Kobayashi, Shuichiro Yokoyama
The conventional slow-roll approximation is broken in the so-called "ultra slow-roll" models of inflation, for which the inflaton potential is exactly (or extremely) flat. The inte…