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Related papers: Energy Conditions in Non-local Gravity

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We study and derive the energy conditions in generalized non-local gravity, which is the modified theory of general relativity (GR) obtained by adding a term $m^{2n-2}R\Box^{-n}R$ to the Einstein-Hilbert action. Moreover, in order to get…

General Relativity and Quantum Cosmology · Physics 2017-08-02 Ya-Bo Wu , Xue Zhang , Bo-Hai Chen , Nan Zhang , Meng-Meng Wu

A nonlocal gravity model with a function $f(\Box^{-1} R)$, where $\Box$ is the d'Alembert operator, is considered. The algorithm, allowing to reconstruct $f(\Box^{-1} R)$, corresponding to the given Hubble parameter and the state parameter…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-18 Sergey Yu. Vernov

A nonlocal gravity model, which does not assume the existence of a new dimensional parameter in the action and includes a function $f(\Box^{-1} R)$, with $\Box$ the d'Alembertian operator, is considered. The model is proven to have de…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-08 E. Elizalde , E. O. Pozdeeva , S. Yu. Vernov

A nonlocal gravity model is considered which does not assume the existence of a new dimensional parameter in the action and includes a function $f(\Box^{-1} R)$, with $\Box$ the d'Alembertian operator. Using a reconstruction procedure for…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-06 E. Elizalde , E. O. Pozdeeva , S. Yu. Vernov

The cosmological dynamics of a non-locally corrected gravity theory, involving a power of the inverse d'Alembertian, is investigated. Casting the dynamical equations into local form, the fixed points of the models are derived, as well as…

General Relativity and Quantum Cosmology · Physics 2018-11-06 E. Elizalde , S. D. Odintsov , E. O. Pozdeeva , S. Yu. Vernov

We consider Non-local Gravity in view to obtain stable and traversable wormhole solutions. In particular, the class of Non-local Integral Kernel Theories of Gravity, with the inverse d'Alembert operator in the gravitational action, is taken…

General Relativity and Quantum Cosmology · Physics 2022-11-28 Salvatore Capozziello , Nisha Godani

In this paper, we briefly review highlights of nonlocal de Sitter gravity based on the nonlocal term $ \sqrt{R - 2\Lambda}\ \mathcal{F}(\Box)\ \sqrt{R - 2\Lambda }$ in the Einstein-Hilbert action without matter sector. This nonlocal de…

General Relativity and Quantum Cosmology · Physics 2023-12-29 Ivan Dimitrijevic , Branko Dragovich , Zoran Rakic , Jelena Stankovic

A nonlocal gravity model which does not assume the existence of a new dimensional parameter in the action and includes a function $f(\Box^{-1} R)$, with $\Box$ the d'Alembertian operator, is studied. By specifying an exponential form for…

High Energy Physics - Theory · Physics 2013-07-24 Emilio Elizalde , Ekaterina O. Pozdeeva , Sergey Yu. Vernov , Ying-li Zhang

In this paper, we investigate a nonlocal modification of general relativity (GR) with action $S = \frac{1}{16\pi G} \int [ R- 2\Lambda + (R-4\Lambda) \, \mathcal{F}(\Box) \, (R-4\Lambda) ] \, \sqrt{-g}\; d^4x ,$ where $\mathcal{F} (\Box) =…

General Relativity and Quantum Cosmology · Physics 2020-06-30 I. Dimitrijevic , B. Dragovich , A. S. Koshelev , Z. Rakic , J. Stankovic

This paper is devoted to a simple nonlocal de Sitter gravity model and its exact vacuum cosmological solutions. In the Einstein-Hilbert action with $\Lambda$ term, we introduce nonlocality by the following way: $R - 2 \Lambda =…

General Relativity and Quantum Cosmology · Physics 2022-12-28 Ivan Dimitrijevic , Branko Dragovich , Zoran Rakic , Jelena Stankovic

We discuss a nonlocal modification of gravity obtained adding a term $m^2 R\,\Box^{-2}R$ to the Einstein-Hilbert action. We find that the mass parameter $m$ only affects the non-radiative sector of the theory, while the graviton remains…

High Energy Physics - Theory · Physics 2014-07-30 Michele Maggiore , Michele Mancarella

We consider nonlocal modification of the Einstein theory of gravity in framework of the pseudo-Riemannian geometry. The nonlocal term has the form $\mathcal{H}(R) \mathcal{F}(\Box)\mathcal {G}(R)$, where $\mathcal{H}$ and $\mathcal{G}$ are…

High Energy Physics - Theory · Physics 2015-08-25 Ivan Dimitrijevic , Branko Dragovich , Jelena Grujic , Zoran Rakic

In this paper we have investigated the cosmological dynamics of non-locally corrected gravity involving a function of the inverse d'Alembertian of the Ricci scalar, $f(\Box^{-1} R))$. Casting the dynamical equations into local form, we…

High Energy Physics - Theory · Physics 2008-11-26 S. Jhingan , S. Nojiri , S. D. Odintsov , M. Sami , I Thongkool , S. Zerbini

A non-local gravity model, which includes a function $f(\Box^{-1} R)$, where $\Box$ is the d'Alembert operator, is considered. For the model with an exponential $f(\Box^{-1} R)$ de Sitter solutions are explored, without any restrictions on…

General Relativity and Quantum Cosmology · Physics 2019-10-30 E. Elizalde , E. O. Pozdeeva , S. Yu. Vernov

We study the Energy Conditions in modified $f(G)$ gravity, with $G$ being the topological Gauss-Bonnet term. Then we use the cosmographic parameters to constrain the functional form of the gravitational action and investigate the…

General Relativity and Quantum Cosmology · Physics 2026-03-18 Francesco Bajardi

The aim of this paper is to introduce a new modified gravity theory named as $f(\mathcal{G},T)$ gravity ($\mathcal{G}$ and $T$ are the Gauss-Bonnet invariant and trace of the energy-momentum tensor, respectively) and investigate energy…

General Relativity and Quantum Cosmology · Physics 2016-12-21 M. Sharif , Ayesha Ikram

We consider nonlocal modified Einstein gravity without matter, where nonlocal term has the form $P(R) F(\Box) Q(R)$. For this model, in this paper we give the derivation of the equations of motion in detail. This is not an easy task and…

High Energy Physics - Theory · Physics 2019-02-26 Ivan Dimitrijevic , Branko Dragovich , Zoran Rakic , Jelena Stankovic

We study the energy conditions in the framework of the modi- fied gravity with higher-derivative torsional terms in the action. We discuss the viability of the model by studying the energy conditions in terms of the cosmographical…

General Relativity and Quantum Cosmology · Physics 2017-06-07 Tahereh Azizi , Miysam Gorjizadeh

In this paper we study a model of modified gravity with non-minimal coupling between a general function of the Gauss-Bonnet invariant, $f(G)$, and matter Lagrangian from the point of view of the energy conditions. Such model has been…

General Physics · Physics 2015-06-03 A. Banijamali , B. Fazlpour , M. R. Setare

We investigate the cosmological dynamics of nonlocally corrected gravity involving a function of the inverse d'Alembertian acting on the Gauss-Bonnet term. Casting the dynamical equations in local form, we derive the reconstruction…

General Relativity and Quantum Cosmology · Physics 2020-03-12 Emilio Elizalde , Ekaterina O. Pozdeeva , Sergey Yu. Vernov
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