English
Related papers

Related papers: II. A GR Source Term $T^{\mu \nu}$ For Dark Matter

200 papers

We find the distribution function f(E) for dark matter (DM) halos in galaxies and the corresponding equation of state from the (empirical) DM density profiles derived from observations. We solve for DM in galaxies the analogous of the…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-22 H. J. de Vega , N. G. Sanchez

Wherever one talks of dark matter, one does so where there is an observable matter and an associated unsolved dynamical issue to be settled. We promote this observation to the status of an axiom and conjecture that there is a dark companion…

General Relativity and Quantum Cosmology · Physics 2009-03-31 Yousef Sobouti

The evidence for the presence of a concentration of dark matter at the Galactic center is now very compelling. There is no question that the stellar and gas kinematics within 0.01 pc is dominated by under-luminous matter in the form of…

Astrophysics · Physics 2009-10-30 Fulvio Melia , Robert Coker

Spherical density profiles and specific angular momentum profiles of Dark Matter halos found in cosmological N-body simulations have been measured extensively. The distribution of the total angular momentum of dark matter halos is also used…

Astrophysics · Physics 2017-08-23 Tom Abel , Rupert C. Croft , Lars Hernquist

N-body equations of motion in comoving system and expanding background are reformulated in a transformed system with static background and fixed damping. The energy and momentum evolution in dark matter flow are rigorously formulated for…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-22 Zhijie Xu

We consider simple hydrodynamical models of galactic dark matter in which the galactic halo is a self-gravitating and self-interacting gas that dominates the dynamics of the galaxy. Modeling this halo as a sphericaly symmetric and static…

High Energy Physics - Phenomenology · Physics 2007-05-23 Luis G. Cabral-Rosetti , Dario Nunez , Roberto A. Sussman , Tonatiuh Matos

The distribution of shapes of galaxies' dark halos provides a basic test for models of galaxy formation. To-date, few dark halo shapes have been measured, and the results of different methods appear contradictory. Here, we add to the sample…

Astrophysics · Physics 2007-05-23 R. P. Olling , M. R. Merrifield

We consider the possibility that the Milky Way's dark matter halo possesses a non vanishing equation of state. Consequently, we evaluate the contribution due to the speed of sound, assuming that the dark matter content of the galaxy behaves…

A two-fluid dark matter model, in which dark matter is represented as a two-component fluid thermodynamic system, without interaction between the constituent particles of different species, and with each distinct component having a…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Tiberiu Harko , Francisco S. N. Lobo

We consider f(R,T) modified theory of gravity, in which the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar and the trace of the energy-momentum tensor of the matter, in order to investigate the dark-matter…

General Relativity and Quantum Cosmology · Physics 2016-11-02 Raziyeh Zaregonbadi , Mehrdad Farhoudi , Nematollah Riazi

Accepting the Komar mass definition of a source with energy-momentum tensor $T_{\mu\nu}$, and using the thermodynamic pressure definition, we find a relaxed energy-momentum conservation law. Thereinafter, we study some cosmological…

General Physics · Physics 2018-08-14 H. Moradpour , J. P. Morais Graça , I. P. Lobo , I. G. Salako

Despite being a fundamental property of galaxies that dictates the form of the potential, the 3D shape is intrinsically difficult to determine from observations. The improving quality of triaxial modeling methods in recent years has made it…

Astrophysics of Galaxies · Physics 2024-10-16 Lucas M. Valenzuela , Rhea-Silvia Remus , Klaus Dolag , Benjamin A. Seidel

We study physics of clusters of galaxies embedded in the cosmic dark energy background. Under the assumption that dark energy is described by the cosmological constant, we show that the dynamical effects of dark energy are strong in…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-08 G. S. Bisnovatyi-Kogan , A. D. Chernin

It is shown that so-called dark energy could possible be a manifestation of the gravitational vortex producing the "gravitomagnetic" (GM) force field: associated with cosmic matter rotation and inertial spacetime frame dragging. The general…

General Physics · Physics 2018-01-24 Reva Kay Williams

The evidence of the phenomenon for which, in galaxies, the gravitating mass is distributed differently than the luminous mass, increases as new data become available. Furthermore, this discrepancy is well structured and it depends on the…

Astrophysics of Galaxies · Physics 2019-03-11 Paolo Salucci

We present the 21-cm rotation curve of the nearby galaxy M33 out to a galactocentric distance of 16 kpc (13 disk scale-lengths). The rotation curve keeps rising out to the last measured point and implies a dark halo mass larger than 5…

Astrophysics · Physics 2009-10-31 Edvige Corbelli , Paolo Salucci

It is well known that the cosmological constant term in the Einstein field equations can be interpreted as a stress tensor for dark energy. This stress tensor is formally analogous to an elastic constitutive equation in continuum mechanics.…

General Relativity and Quantum Cosmology · Physics 2024-09-02 Nader Inan , Ahmed Farag Ali , Kimet Jusufi , Abdelrahman Yasser

Several independent cosmological tests have shown evidences that the energy density of the Universe is dominated by a dark energy component, which cause the present accelerated expansion. The large scale structure formation can be used to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Lucio Marassi

It is suggested that the apparently disparate cosmological phenomena attributed to so-called 'dark matter' and 'dark energy' arise from the same fundamental physical process: the emergence, from the quantum level, of spacetime itself. This…

General Relativity and Quantum Cosmology · Physics 2017-08-18 R. E. Kastner , S. Kauffman

[Abridged] We analyse the dark matter (DM) halo properties of 127 0.3<z<1.5 star-forming galaxies (SFGs) down to low stellar masses (8<log(Mstar/Msun)<11), using data from the MUSE Hubble Ultra Deep Field Survey and photometry from HST and…

Astrophysics of Galaxies · Physics 2026-04-01 B. I. Ciocan , N. F. Bouché , J. Fensch , W. Mercier , D. Krajnović , J. Richard , T. Contini , A. Jeanneau