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200 papers

In Einstein theory of gravity the initial configuration of metric field and its time derivative are related to matter configuration by four equations called constraints. We use the method of conformal metrics (York Method) to solve…

Astrophysics · Physics 2007-05-23 Houri Ziaeepour

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

The $\omega\to\infty$ limit of Brans-Dicke theory is studied with the help of the conformal transformation approach without resorting, however, to the conformal invariance property of this formalism, that is shown to be spurious.

General Relativity and Quantum Cosmology · Physics 2007-05-23 Israel Quiros

Here we consider a metric-affine theory of gravity in which the gravitational Lagrangian is the scalar curvature. The matter action is allowed to depend also on the torsion and the nonmetricity, which are considered as the field variables…

General Relativity and Quantum Cosmology · Physics 2013-07-17 F. F. Faria

We present a framework for the dynamics of causal sets and coupled matter fields, which is a simplification and generalization of an approach we recently proposed. Given a set of fields including the gravitational one, the main step in…

General Relativity and Quantum Cosmology · Physics 2009-07-28 Roman Sverdlov , Luca Bombelli

Tensorial, spinorial and helicity formalisms of the curvature and conformal curvature dynamics are developed. Equations of linearized gravity within that formalisms are given. Gravitational radiation in linearized gravity in terms of…

General Relativity and Quantum Cosmology · Physics 2025-07-28 Adam Chudecki , Maciej Przanowski

Recently\cite{BQG}, it was shown that quantum effects of matter could be identified with the conformal degree of freedom of the space-time metric. Accordingly, one can introduce quantum effects either by making a scale transformation (i.e.…

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

The coupling of gravity to a scalar field raises a number of interesting questions of principle since the usual minimal coupling obtained by replacing ordinary derivatives with covariant derivatives is not available -- they are the same…

General Relativity and Quantum Cosmology · Physics 2011-10-26 Y. N. Srivastava , J. Swain , A. Widom

In this work we present the general differential geometry of a background in which the space-time has both torsion and curvature with internal symmetries being described by gauge fields, and that is equipped to couple spinorial matter…

General Relativity and Quantum Cosmology · Physics 2022-04-20 Luca Fabbri

A continuum model to study the influence of dislocations on the electronic properties of condensed matter systems is described and analyzed. The model is based on a geometrical formalism that associates a density of dislocations with the…

Mesoscale and Nanoscale Physics · Physics 2012-03-22 Fernando de Juan , Alberto Cortijo , María A. H. Vozmediano

We study higher-order theories of gravitation; in particular, we will focus our attention on the second-order theory, in which conformal symmetry can be implemented.

High Energy Physics - Theory · Physics 2011-04-27 Luca Fabbri

In this work, we study the magnetic effects of gravity in the framework of special relativity. Imposing covariance of the gravitational force with respect to the Lorentz transformations, we show from a thought experiment that a…

General Physics · Physics 2018-05-01 R. S. Vieira , H. B. Brentan

We study a gravitational model whose vacuum sector is invariant under conformal transformations. In this model we investigate the anomalous gravitational coupling of the large-scale matter. In this kind of coupling the large-sale matter is…

High Energy Physics - Theory · Physics 2007-05-23 Hadi Salehi , Yousef Bisabr

During the 2016 International Workshop on Astronomy and Relativistic Astrophysics (IWARA), the question was raised as to if conformal gravity could explain the timely result of McGaugh et. al. 2016 which showed a universal nature found in…

General Physics · Physics 2019-04-10 James G. O'Brien , Thomas L. Chiarelli , Mark A. Falcone , Muhannad H. AlQurashi

The scalar-tensor theory of gravitation has been and still is one of the most widely discussed "alternative theories" to General Relativity (GR). Despite nearly half a century of its age, it continues to attract renewed interests of not…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Yasunori Fujii

An obvious criterion to classify theories of modified gravity is to identify their gravitational degrees of freedom and their coupling to the metric and the matter sector. Using this simple idea, we show that any theory which depends on the…

General Relativity and Quantum Cosmology · Physics 2017-03-01 Xavier Calmet , Iberê Kuntz

We study the properties of 2+1d conformal field theories (CFTs) in a background magnetic field. Using generalized particle-vortex duality, we argue that in many cases of interest the theory becomes gapped, which allows us to make a number…

High Energy Physics - Theory · Physics 2023-12-21 Rufus Boyack , Luca V. Delacrétaz , Éric Dupuis , William Witczak-Krempa

In the present paper we consider a theory of gravity in which not only curvature but also torsion is explicitly present in the Lagrangian, both with their own coupling constant. In particular, we discuss the couplings to Dirac fields and…

General Relativity and Quantum Cosmology · Physics 2012-12-06 Luca Fabbri , Stefano Vignolo , Cosimo Stornaiolo

In the framework of the special theory of relativity, the relativistic theory of gravitation (RTG) is constructed. The energy-momentum tensor density of all the matter fields (including gravitational one) is treated as a source of the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. A. Logunov

We have used a two-dimensional analog of the Hadamard state-condition to study the local constraints on the two-point function of a linear quantum field conformally coupled to a two-dimensional gravitational background. We develop a…

High Energy Physics - Theory · Physics 2009-11-07 H. Salehi , Y. Bisabr