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We describe gauge theories which allow to retrieve a large class of gravitational theories, including, MacDowell-Mansouri gravity and its topological extension to Loop Quantum Gravity via the Pontrjagin characteristic class involving the…

General Relativity and Quantum Cosmology · Physics 2026-01-07 J. Thibaut , S. Lazzarini

Scalar curvature invariants are studied in type N solutions of vacuum Einstein's equations with in general non-vanishing cosmological constant Lambda. Zero-order invariants which include only the metric and Weyl (Riemann) tensor either…

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. Bicak , V. Pravda

In this work, a general class of wormhole geometries in conformal Weyl gravity is analyzed. A wide variety of exact solutions of asymptotically flat spacetimes is found, in which the stress energy tensor profile differs radically from its…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Francisco S. N. Lobo

We consider a gravitational model in a Weyl-Cartan space-time, in which the Weitzenb\"{o}ck condition of the vanishing of the sum of the curvature and torsion scalar is also imposed. Moreover, a kinetic term for the torsion is also included…

General Relativity and Quantum Cosmology · Physics 2013-08-13 Zahra Haghani , Tiberiu Harko , Hamid Reza Sepangi , Shahab Shahidi

We provide a gauge-invariant theory of gravitation in the context of Weyl Integrable Space-Times. After making a brief review of the theory's postulates, we carefully define the observers' proper-time and point out its relation with…

General Relativity and Quantum Cosmology · Physics 2014-10-31 F. P. Poulis , J. M. Salim

A general procedure to find static and axially symmetric, interior solutions to the Einstein equations is presented. All the so obtained solutions, verify the energy conditions for a wide range of values of the parameters, and match…

General Relativity and Quantum Cosmology · Physics 2016-11-07 J. L. Hernandez-Pastora , L. Herrera , J. Martin

We show how to lift a generic non-scale invariant action in Einstein frame into a locally conformally-invariant (or Weyl-invariant) theory and present a new general form for Lagrangians consistent with Weyl symmetry. Advantages of such a…

High Energy Physics - Theory · Physics 2014-02-26 Itzhak Bars , Paul Steinhardt , Neil Turok

We discuss the structure of nonlocal effective action generating the conformal anomaly in classically Weyl invariant theories in curved spacetime. By the procedure of conformal gauge fixing, selecting the metric representative on a…

High Energy Physics - Theory · Physics 2023-11-16 A. O. Barvinsky , W. Wachowski

We analyze the construction of conformal theories of gravity in the realm of teleparallel theories. We first present a family of conformal theories which are quadratic in the torsion tensor and are constructed out of the tetrad field and of…

General Relativity and Quantum Cosmology · Physics 2012-01-19 J. W. Maluf , F. F. Faria

In this paper, we introduce and motivate the studies of Quantum Weyl Gravity (also known as Conformal Gravity). We discuss some appealing features of this theory both on classical and quantum level. The construction of the quantum theory is…

High Energy Physics - Theory · Physics 2021-07-16 Lesław Rachwał , Stefano Giaccari

In this paper, we analyse the well-posedness of the initial value formulation for particular kinds of geometric scalar-tensor theories of gravity, which are based on a Weyl integrable space-time. We will show that, within a frame-invariant…

General Relativity and Quantum Cosmology · Physics 2018-07-09 R. Avalos , I. P. Lobo , T. Sanomiya , C. Romero

In the previous work we introduced a new static cylindrically symmetric vacuum solutions in Weyl coordinates in the context of the metric f(R) theories of gravity\cite{1}. Now we obtain a 2-parameter family of exact solutions which contains…

General Relativity and Quantum Cosmology · Physics 2010-04-23 D. Momeni , H. Gholizade

We show that gravity together with curved spacetime can emerge, at the microscopic scale, from a U(1) gauge field. The gauge boson that carries gravity, of elementary particles, is proved to be a spin one massless and electrically neutral…

General Relativity and Quantum Cosmology · Physics 2009-10-03 Jean Paul Mbelek

We study spherically symmetric solutions in a covariant massive gravity model, which is a candidate for a ghost-free non-linear completion of the Fierz-Pauli theory. There is a branch of solutions that exhibits the Vainshtein mechanism,…

High Energy Physics - Theory · Physics 2011-11-04 Kazuya Koyama , Gustavo Niz , Gianmassimo Tasinato

We explore some of the gravitational features of a uniform ring both in the Newtonian potential theory and in General Relativity. We use a spacetime associated to a Weyl static solution of the vacuum Einstein's equations with ring like…

General Relativity and Quantum Cosmology · Physics 2020-05-13 L. A. D'Afonseca , P. S. Letelier , S. R. Oliveira

We construct a 4-parameter family of inhomogeneous cosmological models, which contains two recently derived 3-parameter families as special cases. The corresponding exact vacuum solution to Einstein's field equations is obtained with…

General Relativity and Quantum Cosmology · Physics 2016-06-03 Jörg Hennig

In the theory of General Relativity, gravity is described by a metric which couples minimally to the fields representing matter. We consider here its "veiled" versions where the metric is conformally related to the original one and hence is…

General Relativity and Quantum Cosmology · Physics 2015-05-19 Nathalie Deruelle , Misao Sasaki

We transcribe into the framework of the torsionful version of the {\epsilon}-formalism of Infeld and van der Waerden the world definition of the Weyl tensor for a curved spacetime that occurs in the realm of Einstein-Cartan's theory. The…

General Relativity and Quantum Cosmology · Physics 2025-01-20 J. G. Cardoso

We describe a method to generate scalar-tensor theories with Weyl symmetry, starting from arbitrary purely metric higher derivative gravity theories. The method consists in the definition of a conformally-invariant metric $\hat{g}_{\mu…

High Energy Physics - Theory · Physics 2023-12-12 Giorgos Anastasiou , Ignacio J. Araya , Avik Chakraborty

We consider some classes of solutions of the static, spherically symmetric gravitational field equations in the vacuum in the brane world scenario, in which our Universe is a three-brane embedded in a higher dimensional space-time. The…

General Relativity and Quantum Cosmology · Physics 2009-11-10 T. Harko , M. K. Mak