Zobrazeno 1 - 10
of 86
pro vyhledávání: '"Saga, Shohei"'
Multipole expansions have been often used for extracting cosmological information from anisotropic quantities in observation. However, which basis of the expansion is best suited to quantify the anisotropies is not a trivial question in any summary s
Externí odkaz:
http://arxiv.org/abs/2406.19669
Autor:
Saga, Shohei, Alonso, David
We investigate the three-dimensional clustering of sources emitting electromagnetic pulses traveling through cold electron plasma, whose radial distance is inferred from their dispersion measure. As a distance indicator, dispersion measure is systema
Externí odkaz:
http://arxiv.org/abs/2404.06049
Primordial magnetic fields (PMFs) are one of the plausible candidates for the origin of the observed large-scale magnetic fields. While many proposals have been made for the generation mechanism of PMFs by earlier studies, it remains a subject of deb
Externí odkaz:
http://arxiv.org/abs/2312.16316
Publikováno v:
A&A 678, A168 (2023)
It is well known that the first structures that form from small fluctuations in a self-gravitating, collisionless and initially smooth cold dark matter (CDM) fluid are pancakes. We study the gravitational force generated by such pancakes just after s
Externí odkaz:
http://arxiv.org/abs/2305.13354
Publikováno v:
Phys.Rev.D 108 (2023) 10, 103513
We consider the gravitational collapse of collisionless matter seeded by three crossed sine waves with various amplitudes, also in the presence of a linear external tidal field. We explore two theoretical methods that are more efficient than standard
Externí odkaz:
http://arxiv.org/abs/2303.12832
Autor:
Minoda, Teppei, Saga, Shohei, Takahashi, Tomo, Tashiro, Hiroyuki, Yamauchi, Daisuke, Yokoyama, Shuichiro, Yoshiura, Shintaro
In the most distant reaches of the Universe, the 21-cm hyperfine transition in neutral hydrogen provides one of the only available tracers of large-scale structure. A number of instruments have been working and planned to measure the 21-cm line signa
Externí odkaz:
http://arxiv.org/abs/2303.07604
Autor:
Taruya, Atsushi, Saga, Shohei
Ultralight bosonic dark matter called fuzzy dark matter (FDM) has attracted much attention as an alternative to the cold dark matter. An intriguing feature of the FDM model is the presence of a soliton core, a stable dense core formed at the center o
Externí odkaz:
http://arxiv.org/abs/2208.06562
We study relativistic effects, arising from the light propagation in an inhomogeneous universe. We particularly investigate the effects imprinted in a cross-correlation function between galaxy positions and intrinsic galaxy shapes (GI correlation). C
Externí odkaz:
http://arxiv.org/abs/2207.03454
The local position invariance (LPI) is one of the three major pillars of Einstein equivalence principle, ensuring the space-time independence on the outcomes of local experiments. The LPI has been tested by measuring the gravitational redshift effect
Externí odkaz:
http://arxiv.org/abs/2112.07727