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Related papers: BF gravity and the Immirzi parameter

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General Relativity (GR) exists in different formulations. They are equivalent in pure gravity but generically lead to distinct predictions once matter is included. After a brief overview of various versions of GR, we focus on metric-affine…

High Energy Physics - Theory · Physics 2023-11-09 Claire Rigouzzo , Sebastian Zell

f(R)-type gravity in the first order formalism is interpreted as Einstein gravity with non-minimal coupling arising from the use of unphysical frame. Identification of the corresponding second order higher-curvature gravity in the physical…

General Relativity and Quantum Cosmology · Physics 2010-11-11 Y. Ezawa , H. Iwasaki , Y. Ohkuwa , T. Uegaki , N. Yamada , T. Yano

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

We study thermodynamics in $f(R)$ gravity with the disformal transformation. The transformation applied to the matter Lagrangian has the form of $\g_{\m\n} = A(\phi,X)g_{\m\n} + B(\phi,X)\pa_\m\f\pa_\n\f$ with the assumption of the…

General Relativity and Quantum Cosmology · Physics 2019-02-14 Chao-Qiang Geng , Wei-Cheng Hsu , Jhih-Rong Lu , Ling-Wei Luo

We develop an explicit model of quantum gravity coupled to the matter fields of the Standard Model, based on the 3-group structure and the 3BF action, within the framework of higher gauge theory. The model is constructed by providing a…

High Energy Physics - Theory · Physics 2026-03-02 Pavle Stipsic , Marko Vojinovic

In this contribution, we re-assess the subject of topological gravity by following the Shift Supersymmetry formalism. The gauge-fixing of the theory goes under the Batallin-Vilkovisky (BV) prescription based on a diagram that contains both…

General Relativity and Quantum Cosmology · Physics 2018-08-09 José A. Lourenço , José A. Helayël Neto , Wesley Spalenza

We consider a possible ways of the dynamics of a homogeneous and isotropic space described by the FLRW metric in the framework of cubic f(R) gravity in the absence of matter. This article points an method for limiting the parameters of…

General Relativity and Quantum Cosmology · Physics 2023-04-20 P. M. Petryakova

We have derived a modified Lane-Emden equation for the Starobinsky model in Palatini gravity which is numerically solvable. Comparing the results to the ones provided by General Relativity we observe a significant difference depending on…

General Relativity and Quantum Cosmology · Physics 2019-01-23 Aneta Wojnar

We propose a new formulation of $f(R)$ gravity, dubbed scalarized $f(R)$ gravity, in which the Legendre transform is included as a dynamical term. This leads to a theory with second-order field equations that describes general relativity…

General Relativity and Quantum Cosmology · Physics 2023-06-07 Spiros Cotsakis , Jose P. Mimoso , John Miritzis

We present a novel reconstruction method of $f(T)$ teleparallel gravity from phenomenological parameterizations of the deceleration parameter or other alternatives. This can be used as a toolkit to produce viable modified gravity scenarios…

General Relativity and Quantum Cosmology · Physics 2019-10-29 W. El Hanafy , G. G. L. Nashed

We generalize the $f(R)$ type gravity models by assuming that the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar $R$ and of the matter Lagrangian $L_m$. We obtain the gravitational field equations in the…

General Relativity and Quantum Cosmology · Physics 2011-02-09 Tiberiu Harko , Francisco S. N. Lobo

Barbero has generalized the Ashtekar canonical transformation to a one-parameter scale transformation $U(\iota)$ on the phase space of general relativity. Immirzi has noticed that in loop quantum gravity this transformation alters the…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Carlo Rovelli , Thomas Thiemann

We examine the relationship between Palatini-like theories of gravity and models incorporating linear generalized uncertainty principles. Additionally, we delve into the thermodynamics of systems comprising both Bose and Fermi gases. Our…

General Relativity and Quantum Cosmology · Physics 2024-04-05 Aneta Wojnar , Débora Aguiar Gomes

We consider metric-affine scenarios where a modified gravitational action is sourced by electrovacuum fields in a three dimensional space-time. Such scenarios are supported by the physics of crystalline structures with microscopic defects…

General Relativity and Quantum Cosmology · Physics 2015-08-13 Cosimo Bambi , M. Ghasemi-Nodehi , D. Rubiera-Garcia

In this note we construct a dual formulation of gravity where the main dynamical object is affine connection. We start with the well known first order Palatini formulation but in (Anti) de Sitter space instead of flat Minkowski space as a…

High Energy Physics - Theory · Physics 2007-05-23 Yu. M. Zinoviev

We propose a novel theory of gravity that by construction is renormalizable, evades Ostragadsky's no-go theorem, is locally scale-invariant in the high-energy limit, and equivalent to general relativity in the low-energy limit. The theory…

General Relativity and Quantum Cosmology · Physics 2020-07-13 Daniel Coumbe

We study nonlinear gravity theories in both the metric and the Palatini (metric-affine) formalisms. The nonlinear character of the gravity lagrangian in the metric formalism causes the appearance of a scalar source of matter in Einstein's…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Gonzalo J. Olmo , William Komp

We apply the modified triplectic formalism for quantizing several popular gauge models - non-abelian antisymmetric tensor field model, W2-gravity and two-dimensional gravity with dynamical torsion. The explicit solutions are obtained for…

High Energy Physics - Theory · Physics 2009-10-31 Bodo Geyer , Petr M. Lavrov , Pavel Yu. Moshin

The quadratic gravity constraints are reformulated in terms of the Newman-Penrose-like quantities. In such a frame language, the field equations represent a linear algebraic system for the Ricci tensor components. In principle, a procedure…

General Relativity and Quantum Cosmology · Physics 2023-02-08 Robert Svarc , Alena Pravdova , David Miskovsky

The non-equivalence between the metric and Palatini formalisms of $f(R)$ gravity is an intriguing feature of these theories. However, in the recently proposed hybrid metric-Palatini gravity, consisting of the superposition of the metric…

General Relativity and Quantum Cosmology · Physics 2013-08-23 Salvatore Capozziello , Tiberiu Harko , Francisco S. N. Lobo , Gonzalo J. Olmo