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Related papers: Jeans analysis in modified gravity: A general form…

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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

Versions of parameterized pseudo-Newtonian gravity theories specially designed for cosmology have been introduced in recent cosmology literature. The modifications demand a zero-pressure fluid in the context of versions of modified…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jai-chan Hwang , Hyerim Noh , Chan-Gyung Park

The generalized and extended uncertainty principles affect the Newtonian gravity and also the geometry of the thermodynamic phase space. Under the influence of the latter, the energy-temperature relation of ideal gas may change. Moreover,…

General Relativity and Quantum Cosmology · Physics 2019-07-31 H. Moradpour , A. H. Ziaie , S. Ghaffari , F. Feleppa

In the weak field limit general relativity reduces, as is well known, to the Newtonian gravitation. Alternative theories of gravity, however, do not necessarily reduce to Newtonian gravitation; some of them, for example, reduce to…

Astrophysics of Galaxies · Physics 2014-11-20 C. S. S. Brandao , J. C. N. de Araujo

We present the first analysis of extended stellar kinematics of elliptical galaxies where a Yukawa--like correction to the Newtonian gravitational potential derived from f(R)-gravity is considered as an alternative to dark matter. In this…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 N. R. Napolitano , S. Capozziello , A. J. Romanowsky , M. Capaccioli , C. Tortora

In this paper, we study the Jeans analysis in the context of energy-momentum-squared gravity (EMSG). More specifically we find the new Jeans mass for non-rotating infinite mediums as the smallest mass scale for local perturbations that can…

General Relativity and Quantum Cosmology · Physics 2020-02-25 Ali Kazemi , Mahmood Roshan , Ivan De Martino , Mariafelicia De Laurentis

We examine the effects of $f(R)$ gravity on Jeans analysis of collapsing dust clouds. We provide a method for testing modified gravity models by their effects on star formation as the presence of $f(R)$ gravity is found to modify the limit…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-06 Jaakko Vainio , Iiro Vilja

Metric theories of gravity are studied, beginning with a general action that is quadratic in curvature and allows infinite inverse powers of the d'Alembertian operator, resulting in infrared non-local extensions of general relativity. The…

High Energy Physics - Theory · Physics 2015-06-22 Aindriu Conroy , Tomi Koivisto , Anupam Mazumdar , Ali Teimouri

A second gradient generalization of Newtonian gravity is presented within the framework of gradient field theory. Weak nonlocality is introduced via first and second gradients of the gravitational field strength in the Lagrangian density.…

General Relativity and Quantum Cosmology · Physics 2020-12-02 Markus Lazar

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

This thesis embarks on a comprehensive investigation of modified gravity theories and their implications on the properties of compact objects. Our primary objective is to shed light on the fundamental nature of gravity by exploring…

General Relativity and Quantum Cosmology · Physics 2024-06-25 Rajes Ghosh

The dynamics of metric perturbations is explored in the gravity theory with anomaly-induced quantum corrections. Our first purpose is to derive the equation for gravitational waves in this theory on the general homogeneous and isotropic…

General Relativity and Quantum Cosmology · Physics 2012-02-21 Julio C. Fabris , Ana M. Pelinson , Filipe de O. Salles , Ilya L. Shapiro

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

In this paper, we analyze the stability of a homogeneous self-gravitating plasma, having a non-zero resistivity. This study provides a generalization of the Jeans paradigm for determining the critical scale above which gravitational…

High Energy Astrophysical Phenomena · Physics 2015-03-19 Daniela Pugliese , Nakia Carlevaro , Massimiliano Lattanzi , Giovanni Montani , Riccardo Benini

We show that fundamental plane of elliptical galaxies can be used to obtain observational constraints on metric theories of gravity. Being it connected to global properties of ellipticals, it can fix parameters of modified gravity.…

General Relativity and Quantum Cosmology · Physics 2020-04-27 Salvatore Capozziello , Vesna Borka Jovanović , Duško Borka , Predrag Jovanović

This paper shows that the ordinary Jeans wave number can be obtained as a limiting case of a more general approach that includes dissipative effects. Corrections to the Jeans critical mass associated to viscosity are established. Some…

Astrophysics · Physics 2016-08-16 L. S. García Colín , Alfredo Sandoval-Villalbazo

We propose a new point of view for interpreting Newton's and Einstein's theories of gravity. By taking inspiration from Continuum Mechanics and its treatment of anisotropies, we formulate new gravitational actions for modified theories of…

General Relativity and Quantum Cosmology · Physics 2015-10-09 Christian G. Boehmer , Nicola Tamanini

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

Modified theories of gravity usually present new degrees of freedom, as well as higher order derivatives, wrong signs in certain terms and complicated couplings already present in the Lagrangian from the beginning or originated by the field…

General Relativity and Quantum Cosmology · Physics 2022-07-28 Adrià Delhom , Alejandro Jiménez-Cano , Francisco José Maldonado Torralba