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The dynamics of self-gravitating fluids is analyzed within the framework of a collisionless Boltzmann equation in the presence of gravitational fields and Poisson equation. Two cases are analyzed: a system with baryonic and dark matter in a…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-06 Gilberto M. Kremer

Jeans instability within the framework of post-Newtonian Boltzmann and Poisson equations are analyzed. The components of the energy-momentum tensor are calculated from a post-Newtonian Maxwell-J\"uttner distribution function. The…

General Relativity and Quantum Cosmology · Physics 2021-10-26 Gilberto M. Kremer

The problem of Jeans gravitational instability is investigated for static and expanding universes within the context of the five and thirteen field theories which account for viscous and thermal effects. For the five-field theory a general…

General Relativity and Quantum Cosmology · Physics 2018-01-23 G. M. Kremer , M. G. Richarte , F. Teston

An analysis of the gravitational instability in presence of dissipative effects is addressed. In particular, the standard Jeans Mechanism and the generalization in treating the Universe expansion are both analyzed when bulk viscosity…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Nakia Carlevaro , Giovanni Montani

The well known Jeans instability is studied for a viscoelastic, gravitational fluid using generalized hydrodynamic equations of motions. It is found that the threshold for the onset of instability appears at higher wavelengths in a…

Solar and Stellar Astrophysics · Physics 2015-06-17 M. S. Janaki , N. Chakrabarti , D. Banerjee

The Jeans analysis is studied in the first post-Newtonian limit. In other words, the relativistic effects on the local gravitational instability are considered for systems where characteristic velocity of the system and corresponding…

High Energy Astrophysical Phenomena · Physics 2017-05-17 Elham Nazari , Ali Kazemi , Mahmood Roshan , Shahram Abbassi

We study the gravitational instability of a general relativistic complex scalar field with a quartic self-interaction in an infinite homogeneous static background. This quantum relativistic Jeans problem provides a simplified framework to…

General Relativity and Quantum Cosmology · Physics 2018-10-24 Abril Suárez , Pierre-Henri Chavanis

A kinetic and hydrodynamic descriptions are developed in order to analyze the instabilities of a granular gas in the presence of a gravitational field. In the kinetic description the Boltzmann equation is coupled with the Poisson equation,…

Statistical Mechanics · Physics 2019-11-26 Gilberto Medeiros Kremer

The concept of Jeans gravitational instability is rediscussed in the framework of nonextensive statistics and its associated kinetic theory. A simple analytical formula generalizing the Jeans criterion is derived by assuming that the…

Astrophysics · Physics 2009-11-07 J. A. S. Lima , R. Silva , J. Santos

Gravitational instability in classical Jeans theory, General Relativity, and modified gravity is considered. The background density increase leads to a faster growth of perturbations in comparison with the standard theory. The transition to…

General Relativity and Quantum Cosmology · Physics 2015-06-22 E. V. Arbuzova , A. D. Dolgov , L. Reverberi

We consider the Jeans instability and the gravitational collapse of the rotating Bose-Einstein Condensate dark matter halos, described by the zero temperature non-relativistic Gross-Pitaevskii equation, with repulsive inter-particle…

General Relativity and Quantum Cosmology · Physics 2020-05-19 Tiberiu Harko

Due to the nonlinearity of the Euler{Poisson equations, it is possible that the nonlinear Jeans instability may lead to a faster density growing rate than the rate in the standard theory of linearized Jeans instability, which motivates us…

Analysis of PDEs · Mathematics 2022-02-15 Chao Liu , Yiqing Shi

In this paper we study the gravitational instability in presence of viscosity. In particular, the standard Jeans Mechanism is analyzed taking into account bulk-viscosity effects in the first-order Newtonian dynamics. We show how the…

General Relativity and Quantum Cosmology · Physics 2012-05-28 Nakia Carlevaro , Giovanni Montani

Dynamics and collapse of collisionless self-gravitating systems is described by the coupled collisionless Boltzmann and Poisson equations derived from $f(R)$-gravity in the weak field approximation. Specifically, we describe a system at…

General Relativity and Quantum Cosmology · Physics 2015-06-03 S. Capozziello , M. De Laurentis , I. De Martino , M. Formisano , S. D. Odintsov

The well-known Jeans criterion describes the onset of instabilities in an infinite, homogeneous, self-gravitating medium supported by pressure. Most realistic astrophysical systems, however, are not isolated - instead they are under the…

Astrophysics of Galaxies · Physics 2015-06-16 Chanda J. Jog

The Jeans stability criterium for gravitational collapse is examined for the case of an inert binary mixture in local equilibrium, neglectinq dissipative effects. The corresponding transport equations are established using kinetic theory…

Statistical Mechanics · Physics 2021-10-18 A. Sandoval-Villalbazo , A. R. Sagaceta-Mejia

We analyze the stability of self-gravitating systems which dynamics is investigated using the collisionless Boltzmann equation, and the modified Poisson equation of Eddington-inspired Born-Infield gravity. These equations provide a…

General Relativity and Quantum Cosmology · Physics 2017-10-31 Ivan De Martino , Antonio Capolupo

Criterion of the Jeans instability of interstellar gas clouds which are gravitationally coupled with weakly interacting massive particles is revisited. It is established that presence of the dark matter always reduces the Jeans length, and…

Astrophysics · Physics 2009-10-30 David Tsiklauri

Jeans instability is derived for the case of a low density self-gravitating gas beyond the Navier-Stokes equations. The Jeans instability criterium is shown to depend on a Burnett coefficient if the formalism is taken up to fourth order in…

Astrophysics · Physics 2009-11-10 L. S. Garcia-Colin , A. Sandoval-Villalbazo

We study the Jeans gravitational instability for a mixture of baryonic and dark matter particles, in the post-Newtonian approximation. We adopt a kinetic model consisting of a coupled system of post-Newtonian collisionless Boltzmann…

General Relativity and Quantum Cosmology · Physics 2023-03-07 Gilberto M. Kremer , Kamel Ourabah
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