English
Related papers

Related papers: Vacuum polarization instead of "dark matter" in a …

200 papers

This paper investigates spheroidal galaxies comprising a self-interacting dark matter halo (SIDM) plus de Vaucouleurs stellar distribution. These are coupled only via their shared gravitational field, which is computed consistently from the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Curtis J. Saxton

In the framework of the unimodular metagravity, with the scalar graviton/graviscalar dark matter, a regular anomalous one-parameter solution to the static spherically symmetric metagravity equations in empty space is found. The solution…

General Relativity and Quantum Cosmology · Physics 2010-10-19 Yu. F. Pirogov

We study the linear polarization of the accretion disk around black holes with a dark matter halo. The interaction of the black hole with the dark matter is modelled by considering an exact solution to the Einstein equations which describes…

General Relativity and Quantum Cosmology · Physics 2025-03-28 Tsanimir Angelov , Rasim Bekir , Galin Gyulchev , Petya Nedkova , Stoytcho Yazadjiev

After a brief introduction to standard cosmology and the dark matter problem in the the Universe, we consider a self-gravitating noninteracting fermion gas at nonzero temperature as a model for the dark matter halo of the Galaxy. This…

High Energy Physics - Phenomenology · Physics 2014-11-17 Neven Bilic , Gary B. Tupper , Raoul D. Viollier

Why do galactic bars rotate with high pattern speeds, when dynamical friction should rapidly couple the bar to the massive, slowly rotating dark halo? This longstanding paradox may be resolved by considering the dynamical interactions…

Astrophysics · Physics 2009-10-31 S. Tremaine , J. P. Ostriker

The late infall of cold dark matter onto an isolated galaxy such as our own produces flows with definite velocity vectors at any physical point in the galactic halo. It also produces caustics which are places where the dark matter density…

Astrophysics · Physics 2016-11-03 P. Sikivie , W. Kinney

We have studied the polarized image of an equatorial emitting ring around a rotating black hole surrounded by a cold dark matter (CDM) halo. Results show that the CDM halo density has the similar effects of the halo's characteristic radius…

General Relativity and Quantum Cosmology · Physics 2023-03-22 Xin Qin , Songbai Chen , Zelin Zhang , Jiliang Jing

The shapes of individual self-gravitating structures of an ensemble of identical, collisionless particles have remained elusive for decades. In particular, a reason why mass density profiles like the Navarro-Frenk-White or the Einasto…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Jenny Wagner

Techniques for inferring the radial and geometric form of dark matter halos and the results they have produced to date are reviewed. Dark halos appear to extend to at least ~50 kpc with total enclosed masses that rise linearly with radius…

Astrophysics · Physics 2007-05-23 Penny D. Sackett

The static interaction of a point charge and a polarisable particle and between two polarisable particles is discussed in vacuo, and force and energy considerations are made. In particular a critical distance is shown (in principle) to…

Classical Physics · Physics 2015-05-19 R. Coïsson

We obtain more straightforwardly some features of dark matter distribution in the halos of galaxies by considering the spherically symmetric space-time, which satisfies the flat rotational curve condition, and the geometric equation of…

General Relativity and Quantum Cosmology · Physics 2021-09-21 Ugur Camci

It has recently been proposed that if the Galactic dark matter halo were triaxial it would induce lumpiness in the velocity distribution of halo stars in the Solar Neighbourhood through orbital resonances. These substructures could…

Astrophysics of Galaxies · Physics 2018-04-12 Casper Hesp , Amina Helmi

We suggest that the eventual gravitational repulsion between matter and antimatter may be a key for understanding of the nature of dark matter and dark energy. If there is gravitational repulsion, virtual particle-antiparticle pairs in the…

General Physics · Physics 2009-10-21 Dragan Slavkov Hajdukovic

We consider the possibility that the dark matter in the halos of galaxies may be in the form of clusters of \macho s within which are embedded cold, dense gas clouds. Microlensing experiments have found evidence that the Galactic halo…

Astrophysics · Physics 2009-10-28 Ortwin Gerhard , Joseph Silk

A standard paradigm is now available for the recent evolution (z < 10) of structure on galactic and larger scales. Most of the matter is assumed to be dark and dissipationless and to cluster hierarchically from gaussian initial conditions.…

Astrophysics · Physics 2007-05-23 Simon D. M. White

The model of galactic halo as a system of the collisionless small neutral particles from the standpoint of kinetic theory is considered. For the equilibrium system with the use of Maxwell-Boltzmann distribution we obtained results which…

General Relativity and Quantum Cosmology · Physics 2011-11-03 Valentin D. Gladush

A model of dark matter and dark energy based on the concept of gravitational polarization is investigated. We propose an action in standard general relativity for describing, at some effective or phenomenological level, the dynamics of a…

Astrophysics · Physics 2008-12-18 Luc Blanchet , Alexandre Le Tiec

If dark matter particle can be decelerated due to its dissipative self scattering, except for sinking at the galaxy scale to speed up structure formation, it can also be accreted onto local celestial bodies such as the Sun, forming a…

High Energy Physics - Phenomenology · Physics 2020-05-29 Ran Huo

The circular polarization of light that planets reflect is often neglected because it is very small compared to the linear polarization. It could, however, provide information on a planet's atmosphere and surface, and on the presence of…

Earth and Planetary Astrophysics · Physics 2018-08-29 Loïc Rossi , Daphne M. Stam

There are two types of fluctuations in the quantum vacuum: type 1 vacuum fluctuations are on shell and can interact with matter in specific, limited ways that have observable consequences; type 2 vacuum fluctuations are off shell and cannot…

Quantum Physics · Physics 2020-03-31 G. B. Mainland , Bernard Mulligan