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Related papers: Tilted Lema\^itre model and the dark flow

200 papers

The Universe expansion rate is modulated around local inhomogeneities due to their gravitational potential. Velocity waves are then observed around galaxy clusters in the Hubble diagram. This paper studies them in a ~738 Mpc wide, with…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-30 Jenny G. Sorce , Roya Mohayaee , Nabila Aghanim , Klaus Dolag , Nicola Malavasi

The local Hubble flow provides a valuable probe of the transition between cosmic expansion and nonlinear gravitational dynamics. On large scales, galaxies follow the linear Hubble law, but within group- and cluster-sized environments,…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-25 David Benisty , Antonino Del Popolo

Theoretical and observational arguments are listed in favor of a new principle of relativity of units of measurements as the basis of a conformal-invariant unification of General Relativity and Standard Model by replacement of all masses…

General Relativity and Quantum Cosmology · Physics 2007-05-23 V. Pervushin , V. Zinchuk , A. Zorin

Cosmic bulk flow--the volume-averaged peculiar velocity of matter--serves as a fundamental test of the Cosmological Principle when probed on gigaparsec (Gpc) scales. Historically, however, measurements of cosmic bulk flow have been limited…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-13 Suroor Seher Gandhi , Matthew C. Johnson , Jordan Krywonos , Michael J. Hudson

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

We propose that the Hubble tension arises due to an unaccounted additional component, that behaves as \emph{matter with pressure}. We demonstrate that this fluid remains subdominant compared to both dust and radiation throughout nearly the…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-25 Youri Carloni , Orlando Luongo , Marco Muccino

We study a parametrization of the deceleration parameter in a tilted universe, namely a cosmological model equipped with two families of observers. The first family follows the smooth Hubble flow, while the second are the real observers…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-01 Kerkyra Asvesta , Lavrentios Kazantzidis , Leandros Perivolaropoulos , Christos G. Tsagas

Phenomena currently attributed to Dark Energy (DE) and Dark Matter (DM) are merely a result of the interplay between gravitational energy density, generated by the contraction of space by matter, and the energy density of the Cosmological…

Astrophysics · Physics 2008-12-25 Shlomo Barak , Elia M Leibowitz

The Sunyaev--Zel'dovich (SZ) effect is a global distortion of the Cosmic Microwave Background (CMB) spectrum as a result of its interaction with a hot electron plasma in the intracluster medium of large structures gravitationally viralized…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-25 Alexander Bonilla , Jairo E. Castillo

Starting from a recently proposed framework for the evaluation of the cosmological averages, we evaluate the higher-order moments for the distribution of a given observable. Then, we explicitly discuss the case of the Hubble-Lema\^itre…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-28 Tiziano Schiavone , Enea Di Dio , Giuseppe Fanizza

In preceding papers of this series, TF relations for galaxies in 24 clusters with radial velocities between 1000 and 9200 km/s (SCI sample) were obtained, a Tully-Fisher (TF) template relation was constructed and mean offsets of each…

Astrophysics · Physics 2009-10-30 R. Giovanelli , M. Haynes , J. Salzer , G. Wegner , L. da Costa , W. Freudling

We study perfect fluid cosmological models with a constant equation of state parameter $\gamma$ in which there are two naturally defined time-like congruences, a geometrically defined geodesic congruence and a non-geodesic fluid congruence.…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. A. Coley , S. Hervik , W. C. Lim

We compute the evolution of spatially flat, mixed cold and hot dark matter (``MDM") models containing both baryonic matter and two kinds of dark matter. The mean final Zeldovich-Sunyaev $y$ parameter is estimated to be $\bar y=(5.4\pm…

Astrophysics · Physics 2009-10-22 Renyue Cen , Jeremiah P. Ostriker

We show that in tilting perfect fluid cosmological models with an ultra-radiative equation of state, generically the tilt becomes extreme at late times and, as the tilt instability sets in, observers moving with the tilting fluid will…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. A. Coley , S. Hervik , W. C. Lim

The observed accelerated expansion of the Universe may be explained by dark energy or the breakdown of general relativity (GR) on cosmological scales. When the latter case, a modified gravity scenario, is considered, it is often assumed…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-04 Jiro Matsumoto , Teppei Okumura , Misao Sasaki

Recent combined analyses of the CMB and galaxy cluster data reveal unexpectedly large and anisotropic peculiar velocity fields at large scales. We study cosmic models with included vorticity, acceleration and total angular momentum of the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-18 Davor Palle

A hyperaccretion flow around a stellar mass black hole is thought to be the most plausible engine that powers gamma-ray bursts (GRBs). The flow efficiently cools via neutrino emission at >~ 0.003-0.01 M_sun s^{-1} (corresponding to a…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Norita Kawanaka , Shin Mineshige , Tsvi Piran

It has been observed that the locally measured Hubble parameter converges quickest to the background value and the dipole structure of the velocity field is smallest in the reference frame of the Local Group of galaxies. We study the…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-11 David Kraljic , Subir Sarkar

We show that by directly correlating the cluster kinetic Sunyaev Zeldovich (KSZ) flux, the cluster peculiar velocity power spectrum can be measured to $\sim 10%$ accuracy by future large sky coverage KSZ surveys. This method is almost free…

Astrophysics · Physics 2007-05-23 Pengjie Zhang , Albert Stebbins , Roman Juszkiewicz , Hume Feldman

Future multifrequency microwave background experiments with arcminute resolution and micro-Kelvin temperature sensitivity will be able to detect the kinetic Sunyaev-Zeldovich (kSZ) effect, providing a way to measure radial peculiar…

Astrophysics · Physics 2008-11-26 Suman Bhattacharya , Arthur Kosowsky