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Related papers: F(R) cosmology via Noether symmetry and lambda-Cha…

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One of the most favourable extensions of General Relativity is the $f(R)$ gravity. $f(R)$ gravity in Palatini formalism can be a realistic alternative to the dark energy problem. In this work we study a recently introduced dark energy…

General Relativity and Quantum Cosmology · Physics 2022-05-20 Dhruba Jyoti Gogoi , Umananda Dev Goswami

We construct a cosmological model from the inception of the Friedmann-Lem\^aitre-Robertson-Walker metric into the field equations of the f(R,L_m) gravity theory, with R being the Ricci scalar and L_m being the matter lagrangian density. The…

General Relativity and Quantum Cosmology · Physics 2024-03-21 B. S. Gonçalves , P. H. R. S. Moraes , B. Mishra

We consider FLRW cosmological models for perfect fluid (with rho as the energy density) in the frame work of the f(rho) modified theory of gravity [V. N. Tunyak, Russ. Phys. J. 21, 1221 (1978); J. R. Ray, L. L. Smalley, Phys. Rev. D. 26,…

General Physics · Physics 2011-07-05 Yaoming Shi

We consider a class of metric f(R) modified gravity theories, analyze them in the context of a Friedmann-Robertson-Walker cosmology and confront the results with some of the known constraints imposed by observations. In particular, we focus…

General Relativity and Quantum Cosmology · Physics 2012-06-11 Luisa G. Jaime , Leonardo Patino , Marcelo Salgado

General cosmological models with spinor and scalar fields playing the role of gravitational sources are analyzed. The Noether symmetry approach is taken as a criterion to constrain the undefined potentials and couplings of the generic…

General Relativity and Quantum Cosmology · Physics 2013-10-15 Gilberto M. Kremer , Rudinei C. de Souza

In this letter, we explore the $f(Q,T_{\mu\nu}T^{\mu \nu})$ gravity theory, building upon the foundations laid by the $f(Q)$ and $f(Q,T)$ gravity theories. Here, $Q$ represents non-metricity and $T_{\mu\nu}$ stands for the energy-momentum…

General Relativity and Quantum Cosmology · Physics 2025-05-07 Aaqid Bhat , P. K. Sahoo

We explore the recently introduced modified Gauss-Bonnet gravity [1], $f(\mathcal{G},T)$ pragmatic with $\mathcal{G}$, the Gauss-Bonnet term, and ${T}$, the trace of the energy-momentum tensor. Noether symmetry approach has been used to…

General Physics · Physics 2017-01-31 M. Farasat Shamir , Mushtaq Ahmad

We describe gauge theories which allow to retrieve a large class of gravitational theories, including, MacDowell-Mansouri gravity and its topological extension to Loop Quantum Gravity via the Pontrjagin characteristic class involving the…

General Relativity and Quantum Cosmology · Physics 2026-01-07 J. Thibaut , S. Lazzarini

It has been shown earlier that Noether symmetry does not admit a form of F(R) corresponding to an action in which F(R) is coupled to scalar-tensor action for gravity or even for pure F(R) gravity taking anisotropic model into account. Here,…

General Relativity and Quantum Cosmology · Physics 2013-11-12 Nayem Sk. , Abhik Kumar Sanyal

The thermodynamical aspects of the conformal time scale factor duality (SFD) of cosmological models within Einstein Gravity are investigated. We derive the SFD transformations of the thermodynamical quantities describing the thermal…

High Energy Physics - Theory · Physics 2017-03-01 G. M. Sotkov , A. L. Alves Lima , U. Camara da Silva

In this work a new non-minimally coupled model is presented, where a generic function $f(R)$ of the scalar curvature factors the usual Einstein-Hilbert action functional, motivated by relevant results obtained from similar models. Its…

General Relativity and Quantum Cosmology · Physics 2016-11-22 R. P. L. Azevedo , J. Páramos

We analyse f(R) modifications of Einstein's gravity as dark energy models in the light of their connection with chameleon theories. Formulated as scalar-tensor theories, the f(R) theories imply the existence of a strong coupling of the…

Astrophysics · Physics 2009-02-23 Philippe Brax , Carsten van de Bruck , Anne-Christine Davis , Douglas J. Shaw

In this work, a cosmological model is considered having two scalar fields minimally coupled to gravity with a mixed kinetic term. The model is characterized by the coupling function and the potential function which are assumed to depend on…

General Relativity and Quantum Cosmology · Physics 2023-02-17 Santu Mondal , Roshni Bhaumik , Sourav Dutta , Subenoy Chakraborty

We discuss an extended Teleparallel gravity models comprising functions of scalar invariants constructed by torsion, torsion Gauss-Bonnet and boundary terms. We adopt the Noether Symmetry Approach to select the functional forms, the first…

General Relativity and Quantum Cosmology · Physics 2019-05-22 Sebastian Bahamonde , Ugur Camci , Salvatore Capozziello

Why is gauge symmetry so important in modern physics, given that one must eliminate it when interpreting what the theory represents? In this paper we discuss the sense in which gauge symmetry can be fruitfully applied to constrain the space…

History and Philosophy of Physics · Physics 2021-05-25 Bryan W. Roberts , Henrique Gomes , Jeremy Butterfield

There are so many ideas that potentially explain the dark energy phenomenon, current research is focusing on a more in-depth analysis of the potential effects of modified gravity on both local and cosmic scales. In this paper we have…

General Relativity and Quantum Cosmology · Physics 2025-11-24 S. H. Shekh , Hira Sohail , Irfan Mahmood , Allah Ditta , Anil Kumar Yadav

This paper explores exact cosmological solutions of anisotropic universe model through Noether symmetry technique in energy-momentum squared gravity. This theory resolves the primordial singularity and provides viable cosmological…

General Relativity and Quantum Cosmology · Physics 2023-05-24 M. Sharif , M. Zeeshan Gul

The starting point in this note is $f(R)$ modified gravity in a cosmological setting. We assume a spatially flat Universe to describe late-time cosmology and the perfect-fluid equation of state $p=\omega\rho$ to model the hypothesized dark…

General Relativity and Quantum Cosmology · Physics 2017-06-13 Peter K. F. Kuhfittig

Since the general theory of relativity (GR) meets some difficulties, it seems that new considerations on the ether theories of gravitation in the history are needed. A theory of gravity based on some new concepts of ether and particles is…

General Physics · Physics 2024-05-09 Xiao-Song Wang

The reconstruction of f(R)-gravity is showed by using an auxiliary scalar field in the context of cosmological evolution, this development provide a way of reconstruct the form of the function f (R) for a given evolution of the Hubble…

High Energy Physics - Theory · Physics 2009-07-22 Diego Sáez-Gómez
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