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Related papers: Experimental Cosmic Statistics I: Variance

200 papers

We perform N-body simulations for $f(T)$ gravity using the ME-Gadget code, in order to investigate for the first time the structure formation process in detail. Focusing on the power-law model, and considering the model-parameter to be…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-12 Yiqi Huang , Jiajun Zhang , Xin Ren , Emmanuel N. Saridakis , Yi-Fu Cai

We introduce the Virgo Consortium's FLAMINGO suite of hydrodynamical simulations for cosmology and galaxy cluster physics. To ensure the simulations are sufficiently realistic for studies of large-scale structure, the subgrid prescriptions…

We present a method to compute the probability distribution function of the (true) Hubble constant and the age of the universe, given the estimate of the Hubble constant in our nearby galaxy samples. Our method takes into account both the…

Astrophysics · Physics 2009-10-28 T. Nakamura , Y. Suto

The Hubble parameter $H(z)$ is directly related to the expansion of our Universe. It can be used to study dark energy and constrain cosmology models. In this paper, we propose that $H(z)$ can be measured using fast radio bursts (FRBs) with…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-27 Q. Wu , Hai Yu , F. Y. Wang

Cosmic variance limits the accuracy of cosmological N-body simulations, introducing bias in statistics such as the power spectrum, halo mass function, or the cosmic shear. We provide new methods to measure and reduce the effect of cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-29 Gábor Rácz , Alina Kiessling , István Csabai , István Szapudi

Gravitational-wave (GW) detections of electromagnetically bright compact binary coalescences can provide an independent measurement of the Hubble constant $H_0$. In order to obtain a measurement that could help arbitrate the existing…

General Relativity and Quantum Cosmology · Physics 2025-03-14 Yiwen Huang , Hsin-Yu Chen , Carl-Johan Haster , Ling Sun , Salvatore Vitale , Jeffrey S. Kissel

Velocity dispersions have been employed as a method to measure masses of clusters. To complement this conventional method, we explore the possibility of constraining cluster masses from the stacked phase space distribution of galaxies at…

Astrophysics of Galaxies · Physics 2019-09-04 Akinari Hamabata , Masamune Oguri , Takahiro Nishimichi

We present the idea that replacing the cosmological constant $\Lambda$ in the $\Lambda$CDM model by a distribution of walls, with very low tension compared to what one would expect from new physics, could help explaining the tension in the…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-13 Colin D. Froggatt , Holger Bech Nielsen

It has been claimed recently that massive sterile neutrinos could bring about a new concordance between observations of the cosmic microwave background (CMB), the large-scale structure (LSS) of the Universe, and local measurements of the…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-30 Boris Leistedt , Hiranya V. Peiris , Licia Verde

Based on the central limit theorem, we discuss the problem of evaluation of the statistical error of Monte Carlo calculations using a time discretized diffusion process. We present a robust and practical method to determine the effective…

Computational Physics · Physics 2017-02-22 François Delyon , Bernard Bernu , Markus Holzmann

Cosmological N-body simulations have been a major tool of theorists for decades, yet many of the numerical issues that these simulations face are still unexplored. This paper measures numerical biases in these large, dark matter-only…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-11 Philip Mansfield , Camille Avestruz

The Hubble Space Telescope (HST) has obtained multi-epoch observations providing the opportunity for a comprehensive variability search aiming to uncover new variables. We have therefore undertaken the task of creating a catalog of variable…

We analyze the statistical properties of bubble models for the large-scale distribution of galaxies. To this aim, we realize static simulations, in which galaxies are mostly randomly arranged in the regions surrounding bubbles. As a first…

Astrophysics · Physics 2015-06-24 Luca Amendola , Stefano Borgani

On the basis of a model system of pillars built of unit cubes, a two-component entropic measure for the multiscale analysis of spatio-compositional inhomogeneity is proposed. It quantifies the statistical dissimilarity per cell of the…

Statistical Mechanics · Physics 2015-05-13 Ryszard Piasecki

Fermi bubbles, the recently observed giant (~10 kpc high) gamma-ray emitting lobes on either side of our Galaxy (Su et al. 2010), appear morphologically connected to the Galactic center, and thus offer a chance to test several models of…

Astrophysics of Galaxies · Physics 2012-01-18 Kastytis Zubovas , Sergei Nayakshin , Andrew King

Determining the spatial curvature ($\Omega_k$) independent of cosmic microwave background observations plays a key role in revealing the physics of the early universe. The Hubble tension is one of the most serious issues in modern…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-01 Sy-Yun Pu , Teppei Okumura , Chian-Chou Chen , Takahiro Nishimichi , Kazuyuki Akitsu

For high- pressure nucleation experiments in upward diffusion cloud chamber, there is the great deviation of predictions of classical nucleation theory from experimental results; the discrepancy is more than 10 orders of magnitude of…

Chemical Physics · Physics 2007-12-13 Sergey P. Fisenko

The Quijote simulations are a set of 44,100 full N-body simulations spanning more than 7,000 cosmological models in the $\{\Omega_{\rm m}, \Omega_{\rm b}, h, n_s, \sigma_8, M_\nu, w \}$ hyperplane. At a single redshift the simulations…

The large-scale statistics of observables such as the galaxy density are chiefly determined by their dependence on the local coarse-grained matter density. This dependence can be measured directly and efficiently in N-body simulations by…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Christian Wagner , Fabian Schmidt , Chi-Ting Chiang , Eiichiro Komatsu

The statistical properties of cosmic structures are well known to be strong probes for cosmology. In particular, several studies tried to use the cosmic void counting number to obtain tight constrains on Dark Energy. In this paper we…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 Jean-Michel Alimi , Paul de Fromont