Zobrazeno 21 - 30
of 962
pro vyhledávání: '"Koyama, Kazuya"'
Autor:
Wang, Yuting, Zhao, Gong-Bo, Koyama, Kazuya, Percival, Will J., Takahashi, Ryuichi, Hikage, Chiaki, Gil-Marín, Héctor, Hahn, ChangHoon, Zhao, Ruiyang, Zhang, Weibing, Mu, Xiaoyong, Yu, Yu, Zhu, Hong-Ming, Ge, Fei
Publikováno v:
Communications Physics, 7, 130 (2024)
The reconstruction method was proposed more than a decade ago to boost the signal of baryonic acoustic oscillations measured in galaxy redshift surveys, which is one of key probes for dark energy. After moving the observed overdensities in galaxy sur
Externí odkaz:
http://arxiv.org/abs/2202.05248
We present $\texttt{matryoshka}$, a suite of neural network based emulators and accompanying Python package that have been developed with the goal of producing fast and accurate predictions of the nonlinear galaxy power spectrum. The suite of emulato
Externí odkaz:
http://arxiv.org/abs/2109.15236
Autor:
Pogosian, Levon, Raveri, Marco, Koyama, Kazuya, Martinelli, Matteo, Silvestri, Alessandra, Zhao, Gong-Bo, Li, Jian, Peirone, Simone, Zucca, Alex
There has been a significant interest in modifications of the standard $\Lambda$ Cold Dark Matter ($\Lambda$CDM) cosmological model prompted by tensions between certain datasets, most notably the Hubble tension. The late-time modifications of the $\L
Externí odkaz:
http://arxiv.org/abs/2107.12992
Autor:
Raveri, Marco, Pogosian, Levon, Martinelli, Matteo, Koyama, Kazuya, Silvestri, Alessandra, Zhao, Gong-Bo
Recently, in [1], we presented the first combined non-parametric reconstruction of the three time-dependent functions that capture departures from the standard cosmological model, $\Lambda$CDM, in the expansion history and gravitational effects on ma
Externí odkaz:
http://arxiv.org/abs/2107.12990
We present a non-linear analysis of perturbations around cosmological solutions in Generalised Massive gravity. This Lorentz invariant theory is an extension of de Rham, Gabadadze, Tolley massive gravity that propagates $5$ degrees of freedom while a
Externí odkaz:
http://arxiv.org/abs/2107.01423
Autor:
Fiorini, Bartolomeo, Koyama, Kazuya, Izard, Albert, Winther, Hans A., Wright, Bill S., Li, Baojiu
Publikováno v:
JCAP09(2021)021
We investigate the viability of producing galaxy mock catalogues with COmoving Lagrangian Acceleration (COLA) simulations in Modified Gravity (MG) models employing the Halo Occupation Distribution (HOD) formalism. In this work, we focus on two theori
Externí odkaz:
http://arxiv.org/abs/2106.05197
Autor:
Brando, Guilherme, Koyama, Kazuya, Wands, David, Zumalacárregui, Miguel, Sawicki, Ignacy, Bellini, Emilio
The N-body gauge allows the introduction of relativistic effects in Newtonian cosmological simulations. Here we extend this framework to general Horndeski gravity theories, and investigate the relativistic effects that the scalar field introduces in
Externí odkaz:
http://arxiv.org/abs/2105.04491
Publikováno v:
Phys. Rev. D 103, 043528 (2021)
We present a model of Early Modified Gravity (EMG) consisting in a scalar field $\sigma$ with a non-minimal coupling to the Ricci curvature of the type $M^2_{\rm pl}+\xi \sigma^2$ plus a cosmological constant and a small effective mass and demonstrat
Externí odkaz:
http://arxiv.org/abs/2011.12934
One of the cornerstones of general relativity is the equivalence principle. However, the validity of the equivalence principle has only been established on solar system scales for standard matter fields; this result cannot be assumed to hold for the
Externí odkaz:
http://arxiv.org/abs/2011.05876