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Related papers: Generalized modified gravity models: the stability…

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Relationship for dynamical properties in the vicinity of fixed points between two-dimensional continuous and its positivity-preserving discretized dynamical systems is studied. Based on linear stability analysis, we reveal the conditions…

Chaotic Dynamics · Physics 2023-04-05 Shousuke Ohmori , Yoshihiro Yamazaki

We provide a new approach to stable ergodicity of systems with dominated splittings, based on a geometrical analysis of global stable and unstable manifolds of hyperbolic points. Our method suggests that the lack of uniform size of Pesin's…

Dynamical Systems · Mathematics 2008-12-16 Martin Andersson

We investigate the relevance of the conformal method by investigating stability issues for the Einstein-Lichnerowicz conformal constraint system in a nonlinear scalar-field setting. We prove the stability of the system with respect to…

Analysis of PDEs · Mathematics 2015-02-17 Bruno Premoselli

In this paper, we study the effects of modification of gravity on the problem of dynamical instability of the spherical relativistic anisotropic interiors. We have considered non-zero influence of expansion scalar throughout during the…

General Relativity and Quantum Cosmology · Physics 2018-07-17 Z. Yousaf , Kazuharu Bamba , M. Z. Bhatti , U. Farwa

For a modified Randall-Sundrum model [Phys. Rev. D 88 (2013) 025048], the graviton equations are derived and the mass spectrum found. The latter includes a massless graviton and a continuum mass with a gap. There is no negative mass-squared…

General Relativity and Quantum Cosmology · Physics 2016-02-17 Shahrokh Parvizi , Mojtaba Shahbazi

The stability of Lattice Boltzmann Equations modelling Shallow Water Equations in the special case of reduced gravity is investigated theoretically. A stability notion is defined as applied in incompressible Navier-Stokes equations in…

Numerical Analysis · Mathematics 2016-10-06 Mapundi K. Banda , Tumelo R. A. Uoane

The stability criteria for spatially flat homogeneous and isotropic cosmological dynamical system is investigated with the interaction of a scalar field endowed with a perfect fluid.In this paper, we depict the dynamical system perspective…

General Relativity and Quantum Cosmology · Physics 2021-01-25 S. Surendra Singh , Chingtham Sonia

Much of standard galaxy dynamics rests on the implicit assumption that the corresponding N-body problem is (near) integrable. This notion although leading to great simplification is by no means a fact. It is therefore important to develop…

Astrophysics · Physics 2008-02-03 Amr El-Zant

Over the last few decades, a plethora of modifications to general relativity have been proposed to solve a host of cosmological and astrophysical problems. Many modified gravity models are now ruled out with further astrophysical…

General Relativity and Quantum Cosmology · Physics 2023-11-15 Surajit Kalita , Shruti Bhatporia , Amanda Weltman

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

The analysis of axisymmetric spacetimes, dynamical or stationary, is usually made in the reduced space. We prove here a stability property of the quo- tient space and use it together with minimal surface techniques to constraint the shape…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Martin Reiris

In this work, we perform a detailed dynamical analysis for the cosmological applications of a nonminimal torsion-matter coupled gravity. Two alternative formalisms are proposed, which enable one to choose between the easier approach for a…

General Relativity and Quantum Cosmology · Physics 2016-01-20 Sante Carloni , Francisco S. N. Lobo , Giovanni Otalora , Emmanuel N. Saridakis

The coupling of baryonic current to the derivative of the curvature scalar, $R$, inherent to gravitational baryogenesis (GBG), leads to a fourth order differential equation of motion for $R$ instead of the algebraic one of General…

General Relativity and Quantum Cosmology · Physics 2023-01-23 E. Arbuzova , A. Dolgov , K. Dutta , R. Rangarajan

We study the condition for the consistency of the G\"{o}del metric with the dynamical Chern-Simons modified gravity. It turns out to be that this compatibility can be achieved only if the cosmological constant is variable in the space.

High Energy Physics - Theory · Physics 2015-03-17 C. Furtado , J. R. Nascimento , A. Yu. Petrov , A. F. Santos

After a brief outlook of the dynamic quantization method and application of the method to gravity the idea of natural solution of cosmological constant problem in inflating Universe is presented.

High Energy Physics - Theory · Physics 2016-09-06 S. N. Vergeles

We study the gravitational collapse in modified gravitational theories. In particular, we analyze a general $f(R)$ model with uniformly collapsing cloud of self-gravitating dust particles. This analysis shares analogies with the formation…

General Relativity and Quantum Cosmology · Physics 2015-06-03 J. A. R. Cembranos , A. de la Cruz-Dombriz , B. Montes Nuñez

The possibility of obtaining an open set of regular cosmological models is discussed. Cylindrical stiff perfect fluid cosmologies are studied in detail. The condition for geodesic completeness is easy to check. A large family of…

General Relativity and Quantum Cosmology · Physics 2009-04-10 L. Fernández-Jambrina , L. M. González-Romero

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 examine the dynamics of a particle in a general rotating quadratic potential, not necessarily stable or isotropic, using a general complex mode formalism. The problem is equivalent to that of a charged particle in a quadratic potential…

Quantum Physics · Physics 2015-06-03 R. Rossignoli , A. M. Kowalski

Modified Gravity (MOG) has been used successfully to explain the rotation curves of galaxies, the motion of galaxy clusters, the Bullet Cluster, and cosmological observations without the use of dark matter or Einstein's cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 J. W. Moffat