192 citations · 2.8k across the 75 of their papers we have counts for
75 papers
Inverted Oscillators for Testing Gravity-induced Quantum Entanglement
Tomohiro Fujita, Youka Kaku, Akira Matsumura +1
In the quest for quantum gravity, we have lacked experimental verification, hampered by the weakness of gravity and decoherence. Recently, various experiments have been proposed to…
Enhancement of quantum gravity signal in an optomechanical experiment
Youka Kaku, Tomohiro Fujita, Akira Matsumura
No experimental evidence of the quantum nature of gravity has been observed yet and a realistic setup with improved sensitivity is eagerly awaited. We find two effects, which can s…
Highly asymmetric probability distribution from a finite-width upward step during inflation
Ryodai Kawaguchi, Tomohiro Fujita, Misao Sasaki
We study a single-field inflation model in which the inflaton potential has an upward step between two slow-roll regimes by taking into account the finite width of the step. We cal…
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…
First results of axion dark matter search with DANCE
Yuka Oshima, Hiroki Fujimoto, Jun'ya Kume +7
Axions are one of the well-motivated candidates for dark matter, originally proposed to solve the strong CP problem in particle physics. Dark matter Axion search with riNg Cavity E…
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…
How does SU()-natural inflation isotropize the universe?
Tomoaki Murata, Tomohiro Fujita, Tsutomu Kobayashi
We study the homogeneous and anisotropic dynamics of pseudoscalar inflation coupled to an SU() gauge field. To see how the initially anisotropic universe is isotropized in such…
Effective Field Theory of Large Scale Structure in modified gravity and application to Degenerate Higher-Order Scalar-Tensor theories
Shin'ichi Hirano, Tomohiro Fujita
In modified gravity, the one-loop matter power spectrum exhibits an ultraviolet divergence as shown in the framework of the degenerate higher-order scalar-tensor theory. To address…
Can primordial parity violation explain the observed cosmic birefringence?
Tomohiro Fujita, Yuto Minami, Maresuke Shiraishi +1
Recently, the cross-correlation between - and -mode polarization of the cosmic microwave background (CMB), which is well explained by cosmic birefringence with rotation angle…
Stochastic formalism for U(1) gauge fields in axion inflation
Tomohiro Fujita, Kyohei Mukaida, Yuichiro Tada
We develop the stochastic formalism for gauge fields that has the Chern-Simons coupling to a rolling pseudo-scalar field during inflation. The Langevin equations fo…
Stochastic effects on observation of ultralight bosonic dark matter
Hiromasa Nakatsuka, Soichiro Morisaki, Tomohiro Fujita +4
Ultralight bosonic particles are fascinating candidates of dark matter (DM). It behaves as classical waves in our Galaxy due to its large number density. There have been various me…
Perturbation theory of LSS in the CDM Universe: exact time evolution and the two-loop power spectrum
Matteo Fasiello, Tomohiro Fujita, Zvonimir Vlah
We derive exact analytic solutions for density and velocity fields to all orders in Eulerian standard perturbation theory for CDM cosmology. In particular, we show that density…
Effective treatment of U(1) gauge field and charged particles in axion inflation
Tomohiro Fujita, Jun'ya Kume, Kyohei Mukaida +1
The axionic inflaton with the Chern-Simons coupling may generate U(1) gauge fields and charged particles simultaneously. In order to incorporate the backreaction from the charged p…
Gravitational waves detectable in laser interferometers from axion-SU(2) inflation
Tomohiro Fujita, Kaname Imagawa, Kai Murai
Chromo-natural inflation (CNI) is an inflationary model where an axion coupled with SU gauge fields acts as the inflaton. In CNI, the gauge fields have nonzero vacuum expectat…
Universality of linear perturbations in SU()-natural inflation
Tomohiro Fujita, Kai Murai, Ryo Namba
We prove the universality of predictions for linear perturbations from the entire class of models of inflation driven by a pseudo-scalar field coupled to an SU() gauge boson, wh…
Inflation with two-form field: the production of primordial black holes and gravitational waves
Tomohiro Fujita, Hiromasa Nakatsuka, Ippei Obata +1
Antisymmetric tensor field (two-form field) is a ubiquitous component in string theory and generally couples to the scalar sector through its kinetic term. In this paper, we propos…
Ultralight dark matter searches with KAGRA gravitational wave telescope
Yuta Michimura, Tomohiro Fujita, Jun'ya Kume +5
Among various dark matter candidates, bosonic ultralight fields with masses below 1~eV are well motivated. Recently, a number of novel approaches have been put forward to search fo…
First observation and analysis of DANCE: Dark matter Axion search with riNg Cavity Experiment
Yuka Oshima, Hiroki Fujimoto, Masaki Ando +9
Dark matter Axion search with riNg Cavity Experiment (DANCE) was proposed to search for axion dark matter [Phys. Rev. Lett. 121, 161301 (2018)]. We aim to detect the rotation and o…
Dark matter Axion search with riNg Cavity Experiment DANCE: Design and development of auxiliary cavity for simultaneous resonance of linear polarizations
Hiroki Fujimoto, Yuka Oshima, Masaki Ando +4
Axion-like particles (ALPs) are undiscovered pseudo-scalar particles that are candidates for ultralight dark matter. ALPs interact with photons slightly and cause the rotational os…
SU()-natural inflation
Tomohiro Fujita, Kyohei Mukaida, Kai Murai +1
We study SU() gauge fields that couple to the inflaton through the Chern-Simons term. We provide a general procedure to construct homogeneous, isotropic, and attractor solutions…
Gravitational wave trispectrum in the axion-SU(2) model
Tomohiro Fujita, Kai Murai, Ippei Obata +1
We study the trispectrum of the gravitational waves (GWs) generated through the dynamics of an axionic spectator field and SU(2) gauge fields during inflation. In non-Abelian gauge…
Axion dark matter search using arm cavity transmitted beams of gravitational wave detectors
Koji Nagano, Hiromasa Nakatsuka, Soichiro Morisaki +3
Axion is a promising candidate for ultralight dark matter which may cause a polarization rotation of laser light. Recently, a new idea of probing the axion dark matter by optical l…
When does the Schwinger Preheating Occur?
So Okano, Tomohiro Fujita
When the inflaton couples to photons and amplifies electric fields, charged particles produced via the Schwinger effect can dominate the universe after inflation, which is dubbed a…
Dark matter Axion search with riNg Cavity Experiment DANCE: Development of control system for long-term measurement
Hiroki Fujimoto, Yuka Oshima, Masaki Ando +4
Axion-like particles (ALPs) are pseudo-scalar particles that are candidates for ultralight dark matter. ALPs interact with photons slightly and cause the rotational oscillation of…