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Related papers: Noether's stars in $f(\cal {R})$ gravity

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Owed to their compactness, neutron stars involve strong gravity and extreme density physics. Nevertheless, at present, there are a variety of problems where progress (at least conceptually) can be made in the context of weak gravity.…

General Relativity and Quantum Cosmology · Physics 2023-03-02 Nils Andersson , Fabian Gittins , Shanshan Yin , Rodrigo Panosso Macedo

We discuss scalar-tensor cosmology with an extra $R^{-1}$ correction by the Noether Symmetry Approach. The existence of such a symmetry selects the forms of the coupling $\omega(\phi)$, of the potential $V(\phi)$ and allows to obtain…

General Relativity and Quantum Cosmology · Physics 2008-11-26 H. Motavali , S. Capozziello , M. Rowshan Almeh Jog

We study a theory of gravity of the form $f(\mathcal{G})$ where $\mathcal{G}$ is the Gauss-Bonnet topological invariant without considering the standard Einstein-Hilbert term as common in the literature, in arbitrary $(d+1)$ dimensions. The…

General Relativity and Quantum Cosmology · Physics 2020-01-30 Francesco Bajardi , Konstantinos F. Dialektopoulos , Salvatore Capozziello

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

We obtain equilibrium solutions for rotating compact stars including the special relativistic effects. The gravity is assumed to be Newtonian, but we used the active mass density, which takes into account all the energies such as motions of…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Jinho Kim , Hee Il Kim , Hyung Mok Lee

Spherically symmetric configurations of the non-interacting massive complex scalar field, representing non-rotating boson stars, are considered within the framework of the modified torsion based $f(T)$ gravity, with $f(T) = T + \alpha \,…

General Relativity and Quantum Cosmology · Physics 2020-10-19 Saša Ilijić , Marko Sossich

We study the structure of neutron stars in f(R) gravity theories with perturbative constraints. We derive the modified Tolman-Oppenheimer-Volkov equations and solve them for a polytropic equation of state. We investigate the resulting…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Alan Cooney , Simon DeDeo , Dimitrios Psaltis

We study relativistic stars in the simplest model of the de Rham-Gabadadze-Tolley massive gravity which describes the massive graviton without ghost propagating mode. We consider the hydrostatic equilibrium, and obtain the modified…

General Relativity and Quantum Cosmology · Physics 2016-06-15 Taishi Katsuragawa , Shin'ichi Nojiri , Sergei D. Odintsov , Masashi Yamazaki

We construct equilibrium configurations for neutron stars using a specific $f(R,T)$ functional form, recently derived through gaussian process applied to measurements of the Hubble parameter. By construction, this functional form serves as…

General Relativity and Quantum Cosmology · Physics 2024-11-15 J. T. Quartuccio , P. H. R. S. Moraes , G. N. Zeminiani , M. M. Lapola

Spherical symmetry in $f(R)$ gravity is discussed in details considering also the relations with the weak field limit. Exact solutions are obtained for constant Ricci curvature scalar and for Ricci scalar depending on the radial coordinate.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. Capozziello , A. Stabile , A. Troisi

The present work deals with Einstein-aether Scalar tensor gravity in the background of homogeneous and isotropic flat FLRW space-time model. The Noether symmetry vector identifies a transformation in the augmented space so that the field…

General Relativity and Quantum Cosmology · Physics 2024-07-12 Dipanakr Laya , Roshni Bhaumik , Sourav Dutta , Subenoy Chakraborty

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

Taking the Noether gauge symmetry approach into account, we find spherically symmetric static black hole solutions of the non-minimal gauge-gravity Lagrangian of the $\mathcal{R}^\beta F^2$ model. At first, we consider a system of…

General Relativity and Quantum Cosmology · Physics 2023-11-13 S. Mahmoudi , S. Hajkhalili , S. H. Hendi

Noether gauge symmetry for F(R) theory of gravity has been explored recently. The fallacy is that, even after setting gauge to vanish, the form of F(R) \propto R^n (where n \neq 1, is arbitrary) obtained in the process, has been claimed to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Nayem Sk. , Abhik Kumar Sanyal

The gravitational aether theory is a modification of general relativity that decouples vacuum energy from gravity, and thus can potentially address the cosmological constant problem. The classical theory is distinguishable from general…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-27 Farbod Kamiab , Niayesh Afshordi

We investigate a conservative formulation of $f(R,T)$ gravity motivated by a key limitation of several existing approaches: the gravitational function is often reconstructed from a chosen equation of state, making the gravity sector…

General Relativity and Quantum Cosmology · Physics 2026-05-12 Ronaldo V. Lobato , Geanderson A. Carvalho , Carlos E. C. Montaña , Jose F. Rodriguez-Ruiz

We have found some new exact static spherically symmetric interior solutions of metric $f(R)$ gravitational theories describing the equilibrium configuration of a star. Then the solution is matched to the exterior solution and thus gives a…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Ali Shojai , Fatimah Shojai

We construct a class of nuclear equations of state based on a schematic potential model, that originates from the work of Prakash et. al. \cite{Prakash-88}, which reproduce the results of most microscopic calculations. The equations of…

Nuclear Theory · Physics 2008-11-26 V. P. Psonis , Ch. C. Moustakidis , S. E. Massen

We consider neutron star configurations in the scalar-tensor theory of gravity with the coupling between the kinetic term of a scalar field and the Einstein tensor (such the model is a subclass of Horndeski gravity). Neutron stars in this…

General Relativity and Quantum Cosmology · Physics 2023-01-18 Pavel E. Kashargin , Sergey V. Sushkov

The present work is devoted to investigate the Noether symmetries of the locally rotationally symmetric Bianchi type I space time in $f(T,B)$ gravity theory which depends on the torsion scalar $T$ and the boundary term $B$. In this theory,…

General Relativity and Quantum Cosmology · Physics 2018-07-16 Yusuf Kucukakca
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