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We investigate the velocity distribution of elliptical galaxies in the framework of Non-local Gravity. According to this approach, it is possible to recover the fundamental plane of elliptical galaxies without the dark matter hypothesis.…

General Relativity and Quantum Cosmology · Physics 2022-09-07 D. Borka , V. Borka Jovanović , Salvatore Capozziello , P. Jovanović

It has been shown in previous work that DARKexp, which is a theoretically derived, maximum entropy, one shape parameter model for isotropic collisionless systems, provides very good fits to simulated and observed dark-matter halos.…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-20 Liliya L. R. Williams , Jens Hjorth , Radoslaw Wojtak

Adaptive SPH and N-body simulations were carried out to study the effect of gasdynamics on the structure of dark matter halos that result from the gravitational instability and fragmentation of cosmological pancakes. Such halos resemble…

Astrophysics · Physics 2007-05-23 Marcelo Alvarez , Paul R. Shapiro , Hugo Martel

Using high-resolution non-radiative hydrodynamic simulations of galaxy clusters we obtain simple analytic formulae for DM and gas distribution in the spherical approximation. We derive fits for the DM density, velocity dispersion and…

Astrophysics · Physics 2008-11-26 Elena Rasia , Giuseppe Tormen , Lauro Moscardini

From the perspective of non-equilibrium statistical mechanics, modeling the velocity distribution of particles in non-equilibrium, steady-state plasmas presents a significant challenge. Under this context, a family of kappa distributions…

Plasma Physics · Physics 2025-09-10 Abiam Tamburrini , Sergio Davis , Pablo S. Moya

In this paper, we present the density, \rho, velocity dispersion, \sigma, and \rho/\sigma^3 profiles of isotropic systems which have the energy distribution, N(E)\propto[\exp(\phi_0-E)-1], derived in Paper I. This distribution, dubbed…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Liliya L. R. Williams , Jens Hjorth

The internal dynamics of a dark matter structure may have the remarkable property that the local temperature in the structure depends on direction. This is parametrized by the velocity anisotropy beta which must be zero for relaxed…

Starting with the well-known NFW dark matter halo distribution, we construct a simple polytropic model for the intracluster medium which is in good agreement with high resolution numerical hydrodynamical simulations, apply this model to a…

Astrophysics · Physics 2009-11-11 Jeremiah P. Ostriker , Paul Bode , Arif Babul

The velocity anisotropy of particles inside dark matter (DM) haloes is an important physical quantity, which is required for the accurate modelling of mass profiles of galaxies and clusters of galaxies. It is typically measured using the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Radoslaw Wojtak , Stefan Gottloeber , Anatoly Klypin

Using cosmological N-body simulations we study the line-of-sight velocity distribution of dark matter haloes focusing on the lowest-order even moments, dispersion and kurtosis, and their application to estimate the mass profiles of…

Astrophysics · Physics 2009-11-13 Radoslaw Wojtak , Ewa L. Lokas , Stefan Gottloeber , Gary A. Mamon

Persisting tensions between the cosmological constraints derived from low-redshift probes and the ones obtained from temperature and polarisation anisotropies of the Cosmic Microwave Background -- although not yet providing compelling…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Marco Baldi , Fergus Simpson

We propose a variational formulation for the nonequilibrium thermodynamics of discrete open systems, i.e., discrete systems which can exchange mass and heat with the exterior. Our approach is based on a general variational formulation for…

Mathematical Physics · Physics 2018-12-05 François Gay-Balmaz , Hiroaki Yoshimura

The methods of non-equilibrium thermodynamics of systems with an interface have been applied to the study of transport processes in semiconductor junctions. A complete phenomenological model for drift-diffusion processes in a junction has…

Condensed Matter · Physics 2015-06-25 Gabriel Gomila , Miguel Rubi

Using cosmological $N$-body simulations of dark matter haloes, we study the effects of non-sphericity, substructure and streaming motions in reproducing the structure and internal kinematics of clusters of galaxies from kinematical…

Astrophysics · Physics 2009-11-10 Teresa Sanchis , Ewa L. Lokas , Gary A. Mamon

This review is a kinetic theory study investigating the effects of inelasticity on the structure of the non-equilibrium states, in particular on the behavior of the velocity distribution in the high energy tails. Starting point is the…

Statistical Mechanics · Physics 2007-05-23 R. Brito , M. H. Ernst

We describe an algorithm for constructing N-body realizations of equilibrium spherical systems. A general form for the mass density rho(r) is used, making it possible to represent most of the popular density profiles found in the…

Astrophysics · Physics 2009-11-10 Stelios Kazantzidis , John Magorrian , Ben Moore

A macroscopically uniform model of a two-dimensional electron system is proposed to study nonequilibrium properties of electrical conduction. By molecular dynamics simulation, the steady state distribution function $P_y$ of electron…

Statistical Mechanics · Physics 2009-07-06 Tatsuro Yuge

Reducing theoretical uncertainties in Galactic dark matter (DM) searches is an important challenge as several experiments are now delving into the parameter space relevant to popular (particle or not) candidates. Since many DM signal…

Astrophysics of Galaxies · Physics 2020-10-20 Thomas Lacroix , Arturo Núñez-Castiñeyra , Martin Stref , Julien Lavalle , Emmanuel Nezri

In the mathematical modeling of strongly nonequilibrium and nonlinear processes in a tornado approach based on the momentum transfer equations with a model function of sources and sinks is used, which puts this approach to the sharpening…

Atmospheric and Oceanic Physics · Physics 2011-09-26 G. P. Bystrai , I. A. Lykov , S. A. Okhotnikov

The dark energy dominated warm dark matter (WDM) model is a promising alternative cosmological scenario. We explore large-scale structure formation in this paradigm. We do this in two different ways: with the halo model approach and with…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Aurel Schneider , Robert E. Smith , Andrea V. Maccio , Ben Moore