Shin‐ichi Hirano

Stochastic Gravitational Wave Background Anisotropies from Inflation with non-Bunch–Davies States

Shingo Akama, Shin‐ichi Hirano, Shuichiro Yokoyama

Abstract It is known that stochastic gravitational wave backgrounds (SGWBs) have anisotropies generated by squeezed-type tensor non-Gaussianities originating from scalar-tensor-tensor (STT) and tensor-tensor-tensor cubic interactions. While the squeezed tensor non-Gaussianities in the standard slow-roll inflation with the Bunch–Davies vacuum state are suppressed …

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Gravitational mode mixing around black holes in scalar-tensor theories with parity-violating terms

Shin‐ichi Hirano, Masashi Kimura, Masahide Yamaguchi

We investigate black holes and gravitational perturbations when both the scalar Gauss-Bonnet and dynamical Chern-Simons gravity sectors coexist in addition to the Einstein-Hilbert term, and both sectors are coupled to a single canonically normalized scalar field. The presence of the scalar Gauss-Bonnet …

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Correction to: Abundance of primordial black holes in peak theory for an arbitrary power spectrum

Chul‐Moon Yoo, Tomohiro Harada, Shin‐ichi Hirano, Kazunori Kohri

The right-hand side of Eq. (25) should be multplied by 3−3. This error is inherited from the previous work [1]. All subsequent explicit expressions for the number density of peaks and primordial black hole abundance (Eqs. (25), (30), (32), (33) and (35)) …

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First test of the consistency relation for the large-scale structure using the anisotropic three-point correlation function of BOSS DR12 galaxies

Naonori S. Sugiyama, Daisuke Yamauchi, Tsutomu Kobayashi, Tomohiro Fujita et autres

ABSTRACT 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 two- and three-point correlation functions (2PCF and 3PCF) of galaxies. We parameterize the …

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New constraints on cosmological modified gravity theories from anisotropic three-point correlation functions of BOSS DR12 galaxies

Naonori S. Sugiyama, Daisuke Yamauchi, Tsutomu Kobayashi, Tomohiro Fujita et autres

ABSTRACT 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 components of galaxy two- and three-point correlation functions (2 and …

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Cosmological gravity probes: Connecting recent theoretical developments to forthcoming observations

Shun Arai, Katsuki Aoki, Y. Chinone, Rampei Kimura et autres

Abstract 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, cosmological observations have been providing more high-quality data, allowing us to explore gravity on cosmological …

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Primordial non-Gaussianity from Galilean Genesis without strong coupling problem

Shingo Akama, Shin‐ichi Hirano

Galilean Genesis is generically plagued with a strong coupling problem, but this can be avoided depending on the hierarchy between a classical energy scale of genesis and a strong coupling scale. In this paper, we investigate whether the models of Galilean Genesis …

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Primordial black hole formation from massless scalar isocurvature

Chul‐Moon Yoo, Tomohiro Harada, Shin‐ichi Hirano, H. Okawa et autres

We numerically study the primordial black hole (PBH) formation by an isocurvature perturbation of a massless scalar field on super Hubble scales in the radiation-dominated Universe. As a first step we perform simulations of spherically symmetric configurations. For the initial condition, we …

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Biogenic Manganese Crust and Zinc Uptake in the River mixed with Groundwater

Yuki Ito, Takahiro Oyama, Shin‐ichi Hirano, Shiro Tanaka et autres

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Primordial black hole formation from massless scalar isocurvature

Chul‐Moon Yoo, Tomohiro Harada, Shin‐ichi Hirano, H. Okawa et autres

We numerically study the primordial black hole (PBH) formation by an isocurvature perturbation of a massless scalar field on super Hubble scales in the radiation-dominated universe. As a first step we perform simulations of spherically symmetric configurations. For the initial condition, we …

jp, tw (code pays fourni par la source)

UV sensitive one-loop matter power spectrum in degenerate higher-order scalar-tensor theories

Shin‐ichi Hirano, Tsutomu Kobayashi, Daisuke Yamauchi, Shuichiro Yokoyama

We study matter density perturbations up to third order and the one-loop matter power spectrum in degenerate higher-order scalar-tensor (DHOST) theories beyond Horndeski. We systematically solve gravitational field equations and fluid equations order by order and find three novel shape functions characterizing …

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Abundance of primordial black holes in peak theory for an arbitrary power spectrum

Chul‐Moon Yoo, Tomohiro Harada, Shin‐ichi Hirano, Kazunori Kohri

Abstract We modify the procedure for estimating the primordial black hole (PBH) abundance proposed in [C.-M. Yoo, T. Harada, J. Garriga, and K. Kohri, Prog. Theor. Exp. Phys. 2018, 123E01 (2018)] so that it can be applied to a broad power spectrum …

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