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Related papers: Constraining Non-local Gravity by S2 star orbits

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In this paper, we study non-local $F(R)$-mimetic gravity. We implement mimetic gravity in the framework of non-local $F(R)$-theories of gravity. Given some specific class of models and using a potential on the mimetic field, we investigate…

General Relativity and Quantum Cosmology · Physics 2016-06-01 Ratbay Myrzakulov , Lorenzo Sebastiani

The emergence of $R^2$ (Starobinsky) inflation from the semi-classical modification of gravity due to matter quantum fields (trace anomaly) clearly points out the importance of fundamental physics and the first principles in the…

High Energy Physics - Theory · Physics 2021-11-09 K. Sravan Kumar

Nonlocal massive gravity can provide an interesting explanation for the late-time cosmic acceleration, with a dark energy equation of state $w_{\rm DE}$ smaller than $-1$ in the past. We derive the equations of linear cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-11 Savvas Nesseris , Shinji Tsujikawa

The goal of this paper is to investigate the detection by GRAVITY of different relativistic effects affecting the astrometric and/or spectroscopic observations of S2 such as the transverse Doppler shift, the gravitational redshift, the…

High Energy Astrophysical Phenomena · Physics 2017-12-13 M. Grould , F. H. Vincent , T. Paumard , G. Perrin

We investigate the cosmological implications of an effective gravitational action, inspired by Sakharov's idea of induced gravity, containing non-local contributions from the operator $\left(\Box +\beta \right)^{-1} R$. The $\beta$ term is…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-23 Leonardo Giani , Oliver Fabio Piattella

General Relativity suffers for two main problems which have not yet been overcome: it predicts spacetime singularities and cannot be formulated as a perturbative renormalizable theory. In particular, many attempts have been made for…

General Relativity and Quantum Cosmology · Physics 2025-02-04 Salvatore Capozziello , Maurizio Capriolo , Amodio Carleo , Gaetano Lambiase

We consider the cosmology of modified gravity models in which Newton's constant is distorted by a function of the inverse d'Alembertian acting on the Ricci scalar. We derive a technique for choosing the distortion function so as to fit an…

General Relativity and Quantum Cosmology · Physics 2009-08-24 C. Deffayet , R. P. Woodard

Stars near the Galactic center reach a few percent of light speed during pericenter passage, which makes post-Newtonian effects potentially detectable. We formulate the orbit equations in Hamiltonian form such that the $O(v^2/c^2)$ and…

Astrophysics of Galaxies · Physics 2009-10-02 Miguel Preto , Prasenjit Saha

Doubly special relativity (DSR) is usually regarded as a low-energy limit of a quantum gravity theory with testable predictions. On the other hand, non-local quantum field theories have been presented as a solution to the inconsistencies…

High Energy Physics - Theory · Physics 2025-02-24 J. J. Relancio , L. Santamaría-Sanz

We consider non-local modifications of General Relativity given by a distortion function in terms of the inverse of the d'Alembert operator. The inclusion of these terms is motivated by the possibility of reproducing the current accelerated…

General Relativity and Quantum Cosmology · Physics 2023-10-06 Salvatore Capozziello , Rocco D'Agostino

Non-local gravity can potentially solve several problems of gravitational field both at Ultra-Violet and Infra-Red scales. However, such an approach has been formulated mainly in metric formalism. In this paper, we discuss non-local…

General Relativity and Quantum Cosmology · Physics 2026-01-12 Salvatore Capozziello , Damianos Iosifidis

During hundred years of General Relativity (GR), many significant gravitational phenomena have been predicted and discovered. General Relativity is still the best theory of gravity. Nevertheless, some (quantum) theoretical and…

High Energy Physics - Theory · Physics 2017-01-10 Ivan Dimitrijevic , Branko Dragovich , Jelena Stankovic , Alexey S. Koshelev , Zoran Rakic

We consider a modification of GR with a special type of a non-local f(R). The structure of the non-local operators is motivated by the string field theory and p-adic string theory. The spectrum is derived explicitly and the ghost-free…

High Energy Physics - Theory · Physics 2019-08-05 I. Dimitrijevic , B. Dragovich , A. S. Koshelev , Z. Rakic , J. Stankovic

Nonlocal gravity is the recent classical nonlocal generalization of Einstein's theory of gravitation in which the past history of the gravitational field is taken into account. In this theory, nonlocality appears to simulate dark matter.…

Astrophysics of Galaxies · Physics 2016-05-31 B. Mashhoon

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

We explore the cosmological implications of the local limit of nonlocal gravity, which is a classical generalization of Einstein's theory of gravitation within the framework of teleparallelism. An appropriate solution of this theory is the…

General Relativity and Quantum Cosmology · Physics 2024-04-17 Javad Tabatabaei , Abdolali Banihashemi , Shant Baghram , Bahram Mashhoon

Metric theories of gravity are studied, beginning with a general action that is quadratic in curvature and allows infinite inverse powers of the d'Alembertian operator, resulting in infrared non-local extensions of general relativity. The…

High Energy Physics - Theory · Physics 2015-06-22 Aindriu Conroy , Tomi Koivisto , Anupam Mazumdar , Ali Teimouri

It is well known that the Noether symmetry approach proves to be very useful not only to fix physically viable cosmological models but also to reduce dynamics and achieve exact solutions. In this work, We examine a formal framework of…

General Relativity and Quantum Cosmology · Physics 2018-09-05 Phongpichit Channuie , Davood Momeni

A nonlocal form of the effective gravitational action could cure the unboundedness of euclidean gravity with Einstein action. On sub-horizon length scales the modified gravitational field equations seem compatible with all present tests of…

General Relativity and Quantum Cosmology · Physics 2015-06-25 C. Wetterich

Nonlocal RT gravity is a successful modified gravity theory, which not only explains the late-time cosmic acceleration but also behaves well in the solar system. Previous analysis generally assumes the auxiliary field $S_i$ vanishes at the…

General Relativity and Quantum Cosmology · Physics 2020-01-06 S. X. Tian , Zong-Hong Zhu