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Related papers: Jeans analysis in fractional gravity

200 papers

A classification of Brans-Dicke theories of gravitation, based on the behaviour of the dimensionless gravitational coupling constant, is given. It is noted that the discussion takes place in the current literature, about which of the two…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Israel Quiros

This thesis investigates compact astrophysical objects within modified theories of gravity, focusing on neutron stars and strange stars. The work studies their internal structure, equilibrium, and stability in gravitational frameworks based…

General Relativity and Quantum Cosmology · Physics 2026-05-26 Sneha Pradhan

We perform a phase space analysis of a generalized modified gravity theory with nonminimally coupling between geometry and matter. We apply the dynamical system approach to this generalized model and find that in the cosmological context,…

General Relativity and Quantum Cosmology · Physics 2016-05-17 Rui An , Xiaodong Xu , Bin Wang , Yungui Gong

To explain the recently reported large-scale spatial variations of the fine structure constant $\alpha$, we apply some models of curvature-nonlinear multidimensional gravity. Under the reasonable assumption of slow changes of all quantities…

General Relativity and Quantum Cosmology · Physics 2013-12-31 K. A. Bronnikov , M. V. Skvortsova

The second post-Newtonian hydrodynamic equations are analyzed within the framework of a plane wave solution. The hydrodynamic equations for the mass and momentum density are coupled with six Poisson equations for the Newtonian and…

General Relativity and Quantum Cosmology · Physics 2023-03-09 Gilberto M. Kremer

A general formalism to find the density profile of a slowly rotating stellar object in modified gravity is presented. We derive a generic Lane-Emden equation and its analytical solution for a wide class of modified theories of gravity.

General Relativity and Quantum Cosmology · Physics 2022-12-23 Shaswata Chowdhury , Pritam Banerjee , Aneta Wojnar

Modified gravity theories have received increased attention lately to understand the late time acceleration of the universe. This viewpoint essentially modifies the geometric components of the universe. Among numerous extension to…

General Relativity and Quantum Cosmology · Physics 2019-05-23 Parth Shah , Gauranga C. Samanta

A general nonperturvative loop quantization procedure for metric modified gravity is reviewed. As an example, this procedure is applied to scalar-tensor theories of gravity. The quantum kinematical framework of these theories is rigorously…

General Relativity and Quantum Cosmology · Physics 2013-04-09 Xiangdong Zhang , Yongge Ma

The works in this portfolio test the hypothesis that it is not possible to extrapolate the Newtonian inverse square law of gravity from Solar System to galaxy scales. In particular, I look into various tests of Modified Newtonian Dynamics…

Astrophysics of Galaxies · Physics 2023-09-26 Indranil Banik

In this work we explore the dynamical system phase space of Einstein-Gauss-Bonnet theory in the cosmological minisuperspace. This approach binds the main features of the theory through a system of autonomous differential equations, in the…

General Relativity and Quantum Cosmology · Physics 2022-11-14 Konstantinos F. Dialektopoulos , Jackson Levi Said , Zinovia Oikonomopoulou

We have found some analytical cosmological solutions to MOdified Gravity (MOG). These solutions describe different evolutionary epochs of an isotropic and homogeneous universe. During each epoch, the evolution of cosmological perturbation…

General Relativity and Quantum Cosmology · Physics 2017-05-04 Fatimah Shojai , Samira Cheraghchi , Hamed Bouzari Nezhad

We consider a modification of the Brans-Dicke gravitational Action Integral inspired by the existence of a minimum length uncertainty for the scalar field. In particular, the kinetic part of the Brans-Dicke scalar field is modified such…

General Relativity and Quantum Cosmology · Physics 2023-01-11 Andronikos Paliathanasis , Genly Leon

We propose a Lorentz-covariant theory of gravity, and explain its theoretical origins in the problem of time in Newtonian physics. In this retarded gravitation theory (RGT), the gravitational force depends upon both retarded position and…

General Physics · Physics 2015-05-27 C. K. Raju

Our paper introduces a new theoretical framework called the Fractional Einstein--Gauss--Bonnet scalar field cosmology, which has important physical implications. Using fractional calculus to modify the gravitational action integral, we…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-12 Bayron Micolta-Riascos , Alfredo D. Millano , Genly Leon , Byron Droguett , Esteban González , Juan Magaña

In this article we investigate mathematically the variant of post-Newtonian mechanics using generalized fractional derivatives. The relativistic-covariant generalization of the classical equations for gravitational field is studied. The…

General Relativity and Quantum Cosmology · Physics 2011-01-21 V. Kobelev

The Newtonian approximation with a nonvanishing nonlocal background field is analyzed for the scalar-tensor nonlocal gravity and nonlocal Gauss-Bonnet gravity. For these two theories, our calculations show that the Newtonian gravitational…

General Relativity and Quantum Cosmology · Physics 2019-03-28 S. X. Tian , Zong-Hong Zhu

The modified Gauss-Bonnet gravity can be motivated by a number of physical reasons, including: the uniqueness of a gravitational Lagrangian in four and higher dimensions and the leading order $\alpha^\prime$ corrections in superstring…

High Energy Physics - Theory · Physics 2017-08-23 Ishwaree P. Neupane

It has been shown in the literature that effective gravitational constants, which are derived from Verlinde's formalism, can be used to introduce the Tsallis and Kaniadakis statistics. This method provides a simple alternative to the usual…

General Relativity and Quantum Cosmology · Physics 2017-03-08 Everton M. C. Abreu , Jorge Ananias Neto , Edesio M. Barboza , Rafael C. Nunes

The Jeans criterion sets the foundation of our understanding of gravitational collapse. Jog studied the fragmentation of gas under external tides and derived a dispersion relation $$ l' = l_{\rm Jeans} \frac{1} {(1 + \lambda_0' / 4 \pi G…

Astrophysics of Galaxies · Physics 2024-03-06 Guang-Xing Li

Gravitational potentials in the cosmos are deeper than expected from observed visible objects, a phenomenon usually attributed to dark matter, presumably in the form of a new fundamental particle. Until such a particle is observed, the jury…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-07 Scott Dodelson