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Related papers: Bulk flows and CMB dipole anisotropy in cosmologic…

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The Local Group (LG) of galaxies is dominated by the M31 and Milky Way (MW) pair, a configuration which suggests that the mass distribution in the LG and its surroundings should be highly anisotropic. We use the APOSTLE cosmological…

Astrophysics of Galaxies · Physics 2023-10-05 Isabel M. E. Santos-Santos , Julio F. Navarro , Alan McConnachie

Analysis of the Pangu N-body simulation validates that the bulk flow of halos follows a Maxwellian distribution which variance is consistent with the prediction of the linear theory of structure formation. We propose that the consistency…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Ming Li , Jun Pan , Liang Gao , Yipeng Jing , Xiaohu Yang , Xuebin Chi , Longlong Feng , Xi Kang , Weipeng Lin , Guihua Shan , Long Wang , Donghai Zhao , Pengjie Zhang

This work investigates the impact of cosmic flows and density perturbations on Hubble constant $H_0$ measurements using nonlinear phase-space reconstructions of the Local Universe (LU). In particular, we rely on 25 constrained N-body…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-24 Steffen Hess , Francisco-Shu Kitaura

The distributions of peculiar velocities of rich clusters and of groups of galaxies are investigated for different cosmological models and are compared with observations. Four cosmological models are studied: standard ($\Omega=1$) CDM,…

Astrophysics · Physics 2009-10-22 Neta A. Bahcall , Mirt Gramann , Renyue Cen

A beginning end-point for galaxy motions within the 10-Mpc Local Volume is constructed by requiring a smooth distribution of (luminous) mass at the time of recombination, which is shown to be equivalent to a smooth Hubble flow at early…

Astrophysics · Physics 2008-11-26 Alan B. Whiting

We revisit our mapping of the `Local Hole', a large underdensity in the local galaxy redshift distribution that extends out to redshift, $z\approx0.05$ and a potential source of outflows that may perturb the global expansion rate and thus…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 T. Shanks , L. M. Hogarth , N. Metcalfe , J. Whitbourn

The {\em bulk flow} in the Local Universe is a collective phenomenon due to the peculiar motions of matter structures, which, instead of moving in random directions, appears to follow an approximate dipole velocity flow. We apply a…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-04 Maria Lopes , Armando Bernui , Camila Franco , Felipe Avila

In this paper, we have derived the field equations in an extended theory of gravity in an anisotropic space time background and in the presence of magnetic field. The physical and geometrical parameters of the models are determined with…

General Relativity and Quantum Cosmology · Physics 2022-07-19 Sankarsan Tarai , Fakhereh Md. Esmaeili , B. Mishra , S. K. Tripathy

The inhomogeneous distribution of matter in the non-linear regime of galaxies, clusters of galaxies and voids is described by an exact, spherically symmetric inhomogeneous solution of Einstein's gravitational field equations, corresponding…

Astrophysics · Physics 2009-11-11 J. W. Moffat

We employ Maximum Likelihood Estimators to examine the Pantheon+ catalogue of Type Ia supernovae for large scale anisotropies in the expansion rate of the Universe. The analyses are carried out in the heliocentric frame, the CMB frame, as…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-02 Animesh Sah , Mohamed Rameez , Subir Sarkar , Christos Tsagas

In this study, we use the merger process of clusters/voids in the role of variable dark energy fluid to alleviate the Hubble tension, which can lead to a balance in the cosmological expansion rate. To reach this target, we will introduce a…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-15 S. Mohammadi , E. Yusofi , M. Mohsenzadeh , M. K. Salem

We analyze the spectrum of cosmic microwave background (CMB) anisotropies in the timescape cosmology: a potentially viable alternative to homogeneous isotropic cosmologies without dark energy. We exploit the fact that the timescape…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 M. Ahsan Nazer , David L. Wiltshire

Recent observations suggest that there are violations of the isotropy of the universe at large scales, an important part of the cosmological principle. In this paper, we use the Cosmic Microwave Background (CMB) data to search for spatial…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-20 Shek Yeung , Ming-Chung Chu

Observations have repeatedly confirmed the presence of large-scale peculiar motions in the universe, commonly referred to as ``bulk flows''. These are vast regions of the observable universe, typically spanning scales of several hundred…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-06 Christos G. Tsagas , Leandros Perivolaropoulos , Kerkyra Asvesta

The largest temperature anisotropy in the cosmic microwave background (CMB) is the dipole. The simplest interpretation of the dipole is that it is due to our motion with respect to the rest frame of the CMB. As well as creating the $\ell$=1…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-25 Raelyn M. Sullivan , Douglas Scott

The low-order kinematic moments of galaxies, namely bulk flow and shear, enables us to test whether theoretical models can accurately describe the evolution of the mass density field in the nearby Universe. We use the so-called etaMLE…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-05 Fei Qin , Cullan Howlett , Lister Staveley-Smith , Tao Hong

The low order moments, such as the bulk flow and shear, of the large scale peculiar velocity field are sensitive probes of the matter density fluctuations on very large scales. In practice, however, peculiar velocity surveys are usually…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-15 Hume A. Feldman , Richard Watkins , Michael J. Hudson

The dipole anisotropy in the Cosmic Microwave Background Radiation (CMBR) has given a peculiar velocity vector 370 km s$^{-1}$ along $l=264^\circ,b=48^\circ$. However, some other dipoles, for instance, from the number counts, sky brightness…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-04 Ashok K. Singal

The Hubble parameters measured by the DESI DR2 BAO observations show a significant discrepancy from the prediction of the standard cosmological model. This discrepancy, together with the long-discussed Hubble tension, may originate from…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-08 Toshifumi Futamase , Reiki Kojima , Masanori Tomonaga

In a concordant $\Lambda$ Cold Dark Matter ($\Lambda$CDM) model, large-angle Cosmic Microwave Background (CMB) temperature anisotropy due to linear perturbations in the local universe is not negligible. We explore a possible role of an…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-09 Kaiki Taro Inoue