English
Related papers

Related papers: Dynamical system analysis of cosmological evolutio…

200 papers

The Aether-Scalar-Tensor (AeST) theory is an extension of General Relativity (GR) which can support Modified Newtonian Dynamics (MOND) behaviour in its static weak-field limit, and cosmological evolution resembling $\Lambda$CDM. We consider…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-05 Amel Durakovic , Constantinos Skordis

There have been many efforts in the last three decades to embed the empirical MOND program into a robust theoretical framework. While many such theories can explain the profile of galactic rotation curves, they usually cannot explain the…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-12 Peter Verwayen , Constantinos Skordis , Céline Bœhm

The Aether Scalar Tensor (AeST) theory is an extension of General Relativity (GR), proposed for addressing galactic and cosmological observations without dark matter. By casting the AeST theory into a $3+1$ form, we determine its full…

General Relativity and Quantum Cosmology · Physics 2024-12-03 Marianthi Bataki , Constantinos Skordis , Tom Zlosnik

The present work is an example of the application of the dynamical system analysis in the context of cosmology. Here cosmic evolution is considered in the background of homogeneous and isotropic flat Friedmann-Lema\^{i}tre-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2020-11-20 Soumya Chakraborty , Sudip Mishra , Subenoy Chakraborty

In the background dynamics of a spatially flat FLRW model of the universe, we investigate an interacting dark energy model in the context of Lyra's geometry. Pressure-less dust is considered as dark matter, mass of which varies with time…

General Relativity and Quantum Cosmology · Physics 2022-05-04 Goutam Mandal , Sujay Kr. Biswas

The recently proposed aether scalar tensor (AeST) model reproduces both the successes of particle dark matter on cosmological scales and those of modified Newtonian dynamics (MOND) on galactic scales. But the AeST model reproduces MOND only…

Astrophysics of Galaxies · Physics 2023-08-23 Tobias Mistele , Stacy McGaugh , Sabine Hossenfelder

In this paper, we present several explicit reconstructions for {the aether scalar tensor (AeST) theory} derived from the background of Friedmann-Lema$\hat{\text{\i}}$tre-Robertson-Walker cosmological evolution. It is shown that the…

General Relativity and Quantum Cosmology · Physics 2024-03-15 Qi-Ming Fu , Meng-Ci He , Tao-Tao Sui , Xin Zhang

We study the phase space dynamics of cosmological models in the theoretical formulations of non-minimal metric-torsion couplings with a scalar field, and investigate in particular the critical points which yield stable solutions exhibiting…

General Relativity and Quantum Cosmology · Physics 2017-08-18 Arshdeep Singh Bhatia , Sourav Sur

Dynamical system theory is a widely used technique in the analysis of cosmological models. Within this framework, the equations describing the dynamics of a model are recast in terms of dimensionless variables, which evolve according to a…

General Relativity and Quantum Cosmology · Physics 2023-08-16 Santiago García-Serna , J. Bayron Orjuela-Quintana , César A. Valenzuela-Toledo , Hernán Ocampo-Durán

Main aim of this work is to give a suitable explanation of present accelerating universe through an acceptable interactive dynamical cosmological model. A three-fluid cosmological model is introduced in the background of…

General Relativity and Quantum Cosmology · Physics 2022-02-16 Giridhari Deogharia , Mayukh Bandyopadhyay , Ritabrata Biswas

The so-called Einstein-Aether theory is General Relativity coupled (at second derivative order) to a dynamical unit time-like vector field (the aether). It is a Lorentz-violating theory, and gained much attention in the recent years. In the…

General Relativity and Quantum Cosmology · Physics 2014-04-16 Hao Wei , Xiao-Peng Yan , Ya-Nan Zhou

We study cosmic evolution based on the fixed points in the dynamical analysis of the Degenerate Higher-Order Scalar-Tensor (DHOST) theories. We consider the DHOST theory in which the propagation speed of gravitational waves is equal to the…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-10 Wittaya Thipaksorn , Khamphee Karwan

We use a dynamical system approach to study the cosmological viability of $f(R,\mathcal{G})$ gravity theories. The method consists of formulating the evolution equations as an autonomous system of ODEs, using suitable variables. The…

General Relativity and Quantum Cosmology · Physics 2018-03-12 Simony Santos da Costa , Fernando V. Roig , Jailson S. Alcaniz , Salvatore Capozziello , Mariafelicia de Laurentis , Micol Benetti

Recently, a model of modified gravity plus single scalar field model was proposed, in which the scalar couples both to the standard Riemannian volume form given by the square root of the determinant of the Riemannian metric, as well as to…

General Relativity and Quantum Cosmology · Physics 2016-12-09 Denitsa Staicova , Michail Stoilov

We propose a model for the dust matter in the cosmological context. The model contains a scalar field with a kinetic term nonminimally coupled to gravity. By investigating the background and perturbative equations, it is demonstrated that…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-25 Amir Ghalee

In this work, we propose a scheme for cosmic evolution in a generalized Rastall gravity. In our approach, the role of dark energy is taken by the non-conserved sector of the stress energy-momentum tensor. The resultant cosmic evolution is…

General Relativity and Quantum Cosmology · Physics 2020-06-08 Kai Lin , Wei-Liang Qian

We use a dynamical systems analysis to investigate the future behaviour of Einstein-Aether cosmological models with a scalar field coupling to the expansion of the aether and a non-interacting perfect fluid. The stability of the equilibrium…

General Relativity and Quantum Cosmology · Physics 2013-03-14 Patrik Sandin , Bassemah Alhulaimi , Alan Coley

In this work we study the phase-space analysis of generalized Rastall gravity (GRG) which has recently been introduced as a modification to the original version of Rastall gravity (RG). In GRG, the coupling parameter assumes a dynamical…

General Relativity and Quantum Cosmology · Physics 2022-06-01 Hamid Shabani , Hooman Moradpour , Amir Hadi Ziaie

In this work, we use the dynamical system approach to explore the cosmological background evolution of the scalar-tensor representation of $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the stress-energy tensor. The…

General Relativity and Quantum Cosmology · Physics 2024-04-04 Tiago B. Gonçalves , João Luís Rosa , Francisco S. N. Lobo

We propose an Einstein-{\ae}ther scalar-tensor cosmological model. In particular in the scalar-tensor Action Integral we introduce the {\ae}ther field with {\ae}ther coefficients to be functions of the scalar field. This cosmological model…

General Relativity and Quantum Cosmology · Physics 2021-07-28 Andronikos Paliathanasis , Genly Leon
‹ Prev 1 2 3 10 Next ›