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Related papers: Dynamical Systems Analysis in Post-Friedmann Param…

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We develop a parameterized post-Friedmann (PPF) framework which describes three regimes of modified gravity models that accelerate the expansion without dark energy. On large scales, the evolution of scalar metric and density perturbations…

Astrophysics · Physics 2008-11-26 Wayne Hu , Ignacy Sawicki

A unified framework for theories of modified gravity will be an essential tool for interpreting the forthcoming deluge of cosmological data. We present such a formalism, the Parameterized Post-Friedmann framework (PPF), which parameterizes…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-08 Tessa Baker , Pedro G. Ferreira , Constantinos Skordis

We have performed the dynamical system analysis to obtain the critical point in which, the value of the geometric and dynamical parameters satisfy the late-time cosmic behavior of the Universe. At the outset, the modified Friedmann…

General Relativity and Quantum Cosmology · Physics 2025-10-30 Rahul Bhagat , B. Mishra

We consider f(R) modified gravity theories in the metric variation formalism and attempt to reconstruct the function f(R) by demanding a background LCDM cosmology. In particular we impose the following requirements: a. A background cosmic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. Fay , S. Nesseris , L. Perivolaropoulos

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

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

With the increasing wealth of high-quality astronomical and cosmological data and the manifold departures from General Relativity in principle conceivable, the development of generalized parametrization frameworks that unify gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-22 Lucas Lombriser

We perform a phase space analysis of a non-minimally coupled modified gravity theory with the Lagrangian density of the form $\frac{1}{2} f_{1}(R)+[1+\lambda f_{2}(R)]{{\cal{L}}_{m}}$, where $f_1(R)$ and $f_2(R)$ are arbitrary functions of…

General Relativity and Quantum Cosmology · Physics 2014-06-03 Tahereh Azizi , Emad Yaraie

In this paper, we derive the field equations of modified Gauss-Bonnet gravity termed as $f(R,G)$ gravity for the non-flat Friedmann-Robertson-Walker (FRW) spacetime. We utilize the dynamical system approach to study the cosmic dynamics of…

General Relativity and Quantum Cosmology · Physics 2025-01-22 Ashutosh Singh

The increasing precision of cosmological data provides us with an opportunity to test general relativity (GR) on the largest accessible scales. Parameterizing modified gravity models facilitates the systematic testing of the predictions of…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-26 Ali Narimani , Douglas Scott

New corrections to General Relativity are considered in the context of modified $f(R)$ gravity, that satisfy cosmological and local gravity constraints. The proposed models behave asymptotically as $R-2\Lambda$ at large curvature and show…

General Relativity and Quantum Cosmology · Physics 2022-01-13 L. N. Granda

There is a distinct possibility that current and future cosmological data can be used to constrain Einstein's theory of gravity on the very largest scales. To be able to do this in a model-independent way, it makes sense to work with a…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-13 Tessa Baker , Pedro G. Ferreira , Constantinos Skordis , Joe Zuntz

In this paper, we have emphasized the stability analysis of the accelerating cosmological models obtained in $f(T)$ gravity theory. The behavior of the models based on the evolution of the equation of state parameter shows phantom-like…

General Relativity and Quantum Cosmology · Physics 2022-05-25 L. K. Duchaniya , Santosh V Lohakare , B. Mishra , S. K. Tripathy

Two accelerating cosmological models are presented in symmetric teleparallel $f(Q)$ gravity, $Q$ be the non-metricity. The models are constructed based on the assumptions of two different functional forms of $f(Q)$ and a dynamically…

General Relativity and Quantum Cosmology · Physics 2022-05-25 S. A. Narawade , Laxmipriya Pati , B. Mishra , S. K. Tripathy

Cosmological approaches of autonomous dynamical system in the framework of $f(T)$ gravity are investigated in this paper. Our methods applied to flat Friedmann-Robertson-Walker equations in $f(T)$ gravity, consist to extract dynamical…

General Relativity and Quantum Cosmology · Physics 2018-05-02 M. G. Ganiou , P. H. Logbo , M. J. S. Houndjo , J. Tossa

In this paper, we perform the dynamical system analysis of the cosmological models framed in the extended teleparallel gravity, the $f (T, B)$ gravity. We use the mapping, $f(T, B)$ $\rightarrow$-$T$+$\tilde{f}(T, B)$, and define the…

General Relativity and Quantum Cosmology · Physics 2023-09-13 S. A. Kadam , Ninaad P. Thakkar , B. Mishra

In this paper, we have performed the dynamical system analysis of $f(T)$ gravity cosmological models at both background and perturbation levels. We have presented three models pertaining to three distinct functional forms of $f(T)$. The…

General Relativity and Quantum Cosmology · Physics 2024-03-20 L. K. Duchaniya , Kanika Gandhi , B. Mishra

The higher-curvature gravity with boundary terms i.e the $f(Q)$ theories, grounded on non-metricity as a fundamental geometric quantity, exhibit remarkable efficacy in portraying late-time universe phenomena. The aim is to delineate…

General Relativity and Quantum Cosmology · Physics 2024-02-20 Pooja Vishwakarma , Parth Shah

We propose a new dynamical system formalism for the analysis of f(R) cosmologies. The new approach eliminates the need for cumbersome inversions to close the dynamical system and allows the analysis of the phase space of f(R)-gravity models…

General Relativity and Quantum Cosmology · Physics 2015-10-27 Sante Carloni

We perform a dynamical system analysis of Myrzakulov or F(R, T) gravity, which is a subclass of affinely connected metric theories, where ones uses a specific but non-special connection, which allows for non-zero curvature and torsion…

General Relativity and Quantum Cosmology · Physics 2022-11-30 G. Papagiannopoulos , Spyros Basilakos , Emmanuel N. Saridakis
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