English
Related papers

Related papers: Easily Interpretable Bulk Flows: Continuing Tensio…

200 papers

Gravitational waves provide a novel and independent measurement of cosmological parameters, offering a promising avenue to address the Hubble tension alongside traditional electromagnetic observations. In the absence of electromagnetic…

General Relativity and Quantum Cosmology · Physics 2025-10-02 Tom Bertheas , Vasco Gennari , Nicola Tamanini

To explain the puzzling situation in the observed bulk flows on scales $\sim 150 h^{-1}$ Mpc ($H_0 = 100 h^{-1}$ km sec$^{-1}$ Mpc$^{-1}$), we consider the observational behavior of spherically symmetric inhomogeneous cosmological models,…

Astrophysics · Physics 2007-05-23 K. Tomita

We have carried out an initial study of a small sample of nearby spiral and barred galaxies with a broad distribution of Hubble types in order to have a first estimate of the magnitude of their secular mass accretion/excretion rates in the…

Astrophysics of Galaxies · Physics 2012-03-27 Xiaolei Zhang , Ronald J. Buta

[abridged] Volume-weighted statistics of large scale peculiar velocity is preferred by peculiar velocity cosmology, since it is free of uncertainties of galaxy density bias entangled in mass-weighted statistics. However, measuring the…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-11 Yu Yu , Jun Zhang , Yipeng Jing , Pengjie Zhang

A macroscopic Coulomb system of identical charged particles with or without a compensating background charge can evolve maintaining spatial homogeneity and isotropy that mimic the cosmological evolution of a universe with repulsive gravity.…

Statistical Mechanics · Physics 2020-05-11 Eugene B. Kolomeisky

We present a machine learning approach using normalising flows for inferring cosmological parameters from gravitational wave events. Our methodology is general to any type of compact binary coalescence event and cosmological model and…

General Relativity and Quantum Cosmology · Physics 2023-10-26 Federico Stachurski , Christopher Messenger , Martin Hendry

I propose a new volume-weighted probability measure for cosmological "multiverse" scenarios involving eternal inflation. The "reheating-volume (RV) cutoff" calculates the distribution of observable quantities on a portion of the reheating…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sergei Winitzki

In Microscopic Particle Image Velocimetry ($\mu$PIV), velocity fields in microchannels are sampled over finite volumes within which the velocity fields themselves may vary significantly. In the past, this has limited measurements often to…

Mesoscale and Nanoscale Physics · Physics 2014-07-31 P. W. Bryant , R. F. Neumann , M. J. B. Moura , M. Steiner , M. S. Carvalho , C. Feger

A hierarchical Bayesian model is applied to the Cosmicflows-3 catalog of galaxy distances in order to derive the peculiar velocity field and distribution of matter within $z \sim 0.054$. The model assumes the $\Lambda$CDM model within the…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-23 R. Graziani , H. M. Courtois , G. Lavaux , Y. Hoffman , R. B. Tully , Y. Copin , D. Pomarède

We obtain estimates of all components of the velocity of a 3D rigid body moving in a viscous incompressible fluid without any symmetry restriction on the shape of the rigid body or the container. The estimates are in terms of suitable norms…

Analysis of PDEs · Mathematics 2023-04-25 Stathis Filippas , Alkis Tersenov

We characterize the radial and angular variance of the Hubble flow in the COMPOSITE sample of 4534 galaxies, on scales in which much of the flow is in the nonlinear regime. With no cosmological assumptions other than the existence of a…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-30 David L. Wiltshire , Peter R. Smale , Teppo Mattsson , Richard Watkins

A method is proposed to estimate the velocity field of an unsteady flow using a limited number of flow measurements. The method is based on a non-linear low-dimensional model of the flow and on expanding the velocity field in terms of…

Optimization and Control · Mathematics 2009-11-13 Marcelo Buffoni , Simone Camarri , Angelo Iollo , Edoardo Lombardi , Maria-Vittoria Salvetti

We create a combined sample of 10,904 late and early-type galaxies from the 2MTF and 6dFGSv surveys in order to accurately measure bulk flow in the local Universe. Galaxies and groups of galaxies common between the two surveys are used to…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-22 Fei Qin , Cullan Howlett , Lister Staveley-Smith , Tao Hong

The current $>3\sigma$ tension between the Hubble constant $H_0$ measured from local distance indicators and from cosmic microwave background is one of the most highly debated issues in cosmology, as it possibly indicates new physics or…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-07 Hao-Yi Wu , Dragan Huterer

Using the 2MASS near-infrared photometry and high signal-to-noise HI 21-cm data from the Arecibo, Green Bank, Nancay, and Parkes telescopes, we calculate the redshift-independent distances and peculiar velocities of 2,018 bright inclined…

Variational multiscale (VMS) methods offer a robust framework for handling under-resolved flow scales without resorting to problem-specific turbulence models. Here, we propose and assess a dynamic, term-by-term VMS stabilized formulation…

Fluid Dynamics · Physics 2026-02-06 Diego Escobar , Douglas Pacheco , Alejando Aguirre , Ernesto Castillo

A novel volume of fluid model (VoF) called explicit volume diffusion (EVD) is developed for the simulation of interfacial flows, including those with turbulence and primary spray atomisation. The EVD model is derived by volume averaging the…

Fluid Dynamics · Physics 2021-06-30 B. Wang , M. J. Cleary , A. R. Masri

Measurements of cosmic flows enable us to test whether cosmological models can accurately describe the evolution of the density field in the nearby Universe. In this paper, we measure the low-order kinematic moments of the cosmic flow…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-01 Fei Qin , David Parkinson , Cullan Howlett , Khaled Said

Gravitational and hydrodynamical perturbations are analysed in a relativistic plasma containing a mixture of interacting fluids characterized by a non-negligible bulk viscosity coefficient. The energy-momentum transfer between the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Massimo Giovannini

(context) Different cosmological data are consistent with an accelerated expansion produced by an exotic matter-energy component, dubbed "dark-energy''. A cosmological constant is a possibility since it satisfies most of the observational…

Astrophysics · Physics 2010-01-15 Sébastien Peirani , José Antonio De Freitas Pacheco