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Related papers: Deflating the Spacetime-Matter Dichotomy

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We consider the reconstruction technique in theories with a single or multiple (phantom and/or canonical) scalar fields. With the help of several examples, it is demonstrated explicitly that the universe expansion history, unifying…

High Energy Physics - Theory · Physics 2008-11-26 Emilio Elizalde , Shin'ichi Nojiri , Sergei D. Odintsov , Diego Sáez-Gómez , Valerio Faraoni

We describe a new type of gravity-matter models where gravity couples in a non-conventional way to two distinct scalar fields providing a unified Lagrangian action principle description of: (a) the evolution of both "early" and "late"…

General Relativity and Quantum Cosmology · Physics 2017-07-25 Eduardo Guendelman , Emil Nissimov , Svetlana Pacheva

In this paper, we study various cosmological parameters and quantities in scalar-tensor gravity from inflation and swampland conjecture. Therefore, by selecting different models such as power-law, exponential, and logarithmic in the…

General Relativity and Quantum Cosmology · Physics 2022-08-19 S. Noori Gashti , J. Sadeghi

We discuss the motivation for high accuracy relativistic gravitational experiments in the Solar System and complementary cosmological tests. We focus our attention on the issue of distinguishing a generic scalar-theory of gravity as the…

Astrophysics · Physics 2008-11-26 Orfeu Bertolami

We consider flat Friedmann-Lema\^{\i}tre-Robertson-Walker cosmological models in the framework of general scalar-tensor theories of gravity with arbitrary coupling functions, set in the Jordan frame, in the cosmological epoch when the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Laur Järv , Piret Kuusk , Margus Saal

In this letter we discuss the possibility of treating the spacetime by itself as a kind of deformable body for which we can define an fundamental lattice, just like atoms in crystal lattices. We show three signs pointing in that direction.…

General Relativity and Quantum Cosmology · Physics 2007-05-30 M. O. Tahim , R. R. Landim , C. A. S. Almeida

We study the dynamical description of scalar-tensor gravity by performing the best-fit analysis for two cases of exponential and power-law form of the potential and scalar field function coupled to the curvature. The models are then tested…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Hossein Farajollahi , Amin Salehi , Mohammad Nasiri

Starting with a field theoretic approach in Minkowski space, the gravitational energy momentum tensor is derived from the Einstein equations in a straightforward manner. This allows to present them as {\it acceleration tensor} = const.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Theo M. Nieuwenhuizen

In this paper, we explore the equivalence between two theories, namely f(R) and scalar-tensor theories of gravity. We use this equivalence to explore several f(R) toy models focusing on the inflation epoch of the early universe. The study…

General Relativity and Quantum Cosmology · Physics 2018-11-21 Joseph Ntahompagaze , Jean Damascene Mbarubukeye , Shambel Sahlu , Amare Abebe

In this article, we discuss the space-time of a global monopole field as a candidate for galactic dark matter in the context of scalar tensor theory.

General Relativity and Quantum Cosmology · Physics 2008-11-26 F. Rahaman , M. Kalam , R. Mondal , B. Raychaudhuri

We explore the idea that the coupling between matter and spacetime is more complex than the one originally envisioned by Einstein. We propose that such coupling takes the form of a new fundamental tensor in the Einstein field equations. We…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Sante Carloni

We study an analytical solution to the Einstein's equations in 2+1-dimensions. The space-time is dynamical and has a line symmetry. The matter content is a minimally coupled, massless, scalar field. Depending on the value of certain…

General Relativity and Quantum Cosmology · Physics 2015-06-25 G. Oliveira-Neto

In any diffeomorphism invariant theory of gravity, one can define a Noether charge arising from the invariance of the Lagrangian under diffeomorphisms. We have determined the Noether charge for scalar-tensor theories of gravity, in which…

General Relativity and Quantum Cosmology · Physics 2025-02-19 Krishnakanta Bhattacharya , Sumanta Chakraborty

In the scalar-tensor theory of gravitation it seems nontrivial to establish if solutions of the cosmological equations in the presence of a cosmological constant behave as attractors independently of the initial values. We develop a general…

High Energy Physics - Theory · Physics 2009-11-06 Kei-ichi Maeda , Yasunori Fujii

Analyzing the static spherically symmetric and rotating ellipsoid solutions in the Newtonian limit of Jordan, Brance - Dicke theory we find the following. In empty space scalar-tensor theories have trivial solution of field equation with…

General Relativity and Quantum Cosmology · Physics 2007-05-23 V. I. Bashkov , S. M. Kozyrev

In the bibliography a certain confusion arises in what regards to the classification of the gravitational theories into scalar-tensor theories and general relativity with a scalar field either minimally or non-minimally coupled to matter.…

General Relativity and Quantum Cosmology · Physics 2020-04-27 Israel Quiros , Roberto De Arcia , Ricardo García-Salcedo , Tame Gonzalez , Francisco Antonio Horta-Rangel

We discuss some of the issues which we encounter when we try to invoke the scalar-tensor theories of gravitation as a theoretical basis of quintessence. One of the advantages of appealing to these theories is that they allow us to implement…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Yasunori Fujii

Recently, it was shown that the quantum effects of the matter, could be used to determine the conformal degree of freedom of the space-time metric. So both gravity and quantum are geometrical features. Gravity determines the causal…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Fatimah Shojai , Ali Shojai , Mehdi Golshani

In cosmology it has become usual to introduce new entities as dark matter and dark energy in order to explain otherwise unexplained observational facts. Here, we propose a different approach treating spacetime as a continuum endowed with…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. Tartaglia , M. Capone

We study the scalar-tensor theory of gravity profoundly in the action level as well as in the thermodynamic level. Contrary to the usual description in the literature about the equivalence in the two conformally connected frames, this paper…

General Relativity and Quantum Cosmology · Physics 2017-05-19 Krishnakanta Bhattacharya , Bibhas Ranjan Majhi