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Related papers: On Nonlocal Modified Gravity and its Cosmological …

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The basic physical structure of the relativistic theory of gravitation is discussed. The significant role that the Hypothesis of Locality plays in relativity theory is elucidated via the phenomenon of spin-rotation coupling. The limitations…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Bahram Mashhoon

We propose a phenomenological approach to the cosmological constant problem based on generally covariant non-local and acausal modifications of four-dimensional gravity at enormous distances. The effective Newton constant becomes very small…

High Energy Physics - Theory · Physics 2007-05-23 Nima Arkani-Hamed , Savas Dimopoulos , Gia Dvali , Gregory Gabadadze

Modified Gravity (MOG) has been used successfully to explain the rotation curves of galaxies, the motion of galaxy clusters, the Bullet Cluster, and cosmological observations without the use of dark matter or Einstein's cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 J. W. Moffat

In the last century, theoretical and experimental developments have established the General Relativity theory as the most successful theory for describing the gravitational phenomenon. On the other hand, in the last two decades, multiple…

General Relativity and Quantum Cosmology · Physics 2025-02-18 Raja Solanki

We systematically review some standard issues and also the latest developments of modified gravity in cosmology, emphasizing on inflation, bouncing cosmology and late-time acceleration era. Particularly, we present the formalism of standard…

General Relativity and Quantum Cosmology · Physics 2021-05-25 S. Nojiri , S. D. Odintsov , V. K. Oikonomou

Nonlocal gravity (NLG) is a classical nonlocal generalization of Einstein's theory of gravitation based on a certain analogy with the nonlocal electrodynamics of media. The history dependence enters NLG through a constitutive relation…

General Relativity and Quantum Cosmology · Physics 2022-10-13 Bahram Mashhoon

Modified gravity has attracted much attention over the last few years and remains a potential candidate for dark energy. In particular, the so-called viable f(R) gravity theories, which are able to both recover General Relativity (GR) and…

General Relativity and Quantum Cosmology · Physics 2016-04-20 Alvaro de la Cruz-Dombriz , Peter K. S. Dunsby , Sulona Kandhai , Diego Saez-Gomez

General Relativity (GR) is consistent with a wide range of experiments/observations from millimeter scales up to galactic scales and beyond. However, there are reasons to believe that GR may need to be modified because it includes…

General Relativity and Quantum Cosmology · Physics 2019-07-17 Leandros Perivolaropoulos , Lavrentios Kazantzidis

The nonlocal theory of accelerated systems is extended to linear gravitational waves as measured by accelerated observers in Minkowski spacetime. The implications of this approach are discussed. In particular, the nonlocal modifications of…

High Energy Physics - Theory · Physics 2009-11-11 Bahram Mashhoon

Modified General Relativity (MGR) is the natural extension of General Relativity (GR). MGR explicitly uses the smooth regular line element vector field $(\bm{X},-\bm{X}) $, which exists in all Lorentzian spacetimes, to construct a…

General Relativity and Quantum Cosmology · Physics 2026-01-27 Gary Nash

Non-local theories of gravity have recently gained a lot of interest because they can suitably represent the behavior of gravitational interaction in the ultraviolet regime. Furthermore, at infrared scales, they give rise to notable…

Astrophysics of Galaxies · Physics 2019-03-06 K. F. Dialektopoulos , D. Borka , S. Capozziello , V. Borka Jovanović , P. Jovanović

This thesis focuses on modifications on Einstein's theory of General Relativity, which could explain the current problems in gravitation and cosmology. More specifically, modifications of the affine structure of the spacetime, which is the…

General Relativity and Quantum Cosmology · Physics 2021-01-28 Francisco José Maldonado Torralba

We study a nonlocally modified gravity model proposed by Deser and Woodard which gives an explanation for current cosmic acceleration. By deriving and solving the equations governing the evolution of the structure in the Universe, we show…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Sohyun Park , Scott Dodelson

We consider a model for gravity that is invariant under global scale transformations. It includes one extra real scalar field coupled non-minimally to the gravity fields. In this model all the dimensionful parameters like the gravitational…

General Relativity and Quantum Cosmology · Physics 2012-02-06 Pankaj Jain , Purnendu Karmakar , Subhadip Mitra , Sukanta Panda , Naveen K. Singh

Introduced herein are the foundations of Global Time Theory (GTT) that further develop the General Relativity (GR). GTT is significantly different from GR in the general physical concepts, but retains 90% of the mathematical structure and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 D. E. Burlankov

It is already known that a simple nonlocal de Sitter gravity model, which we denote as $\sqrt{dS}$ gravity, contains an exact vacuum cosmological solution which mimics dark energy and dark matter and is in very good agreement with the…

General Physics · Physics 2024-04-10 Ivan Dimitrijevic , Branko Dragovich , Zoran Rakic , Jelena Stankovic

The essence of the method of physics is inseparably connected with the problem of interplay between local and global properties of the universe. In the present paper we discuss this interplay as it is present in three major departments of…

General Relativity and Quantum Cosmology · Physics 2008-02-03 Jacques Demaret , Michael Heller , Dominique Lambert

The Newtonian approximation with a nonvanishing nonlocal background field is analyzed for the scalar-tensor nonlocal gravity and nonlocal Gauss-Bonnet gravity. For these two theories, our calculations show that the Newtonian gravitational…

General Relativity and Quantum Cosmology · Physics 2019-03-28 S. X. Tian , Zong-Hong Zhu

We propose a nonlocal scalar-tensor model of gravity with pseudodifferential operators inspired by the effective action of p-adic string and string field theory on flat spacetime. An infinite number of derivatives act both on the metric and…

High Energy Physics - Theory · Physics 2010-12-28 Gianluca Calcagni , Giuseppe Nardelli

It was recently found that there are classes of nonlocal gravity theories that are free of ghosts and singularities in their Newtonian limit [PRL, 108 (2012), 031101]. In these proceedings, a detailed and pedagogical derivation of a main…

General Relativity and Quantum Cosmology · Physics 2013-07-23 Tirthabir Biswas , Tomi Koivisto , Anupam Mazumdar