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Asymptotically anti-de Sitter spacetimes with Poincare invariance along the boundary can describe, via the AdS/CFT correspondence, either relevant deformations of a conformal field theory or non-conformal vacuum states. I consider examples…

High Energy Physics - Theory · Physics 2009-10-31 Steven S. Gubser

Recently, Amendola et al. proposed a geometrical theory of gravity containing higher-order derivative terms. The authors introduced anticurvature scalar $(A)$, which is the trace of the inverse of the Ricci tensor ($A^{\mu\nu} =…

General Relativity and Quantum Cosmology · Physics 2022-11-30 Indranil Das , Joseph P Johnson , S. Shankaranarayanan

In this paper we consider conformal symmetry in the context of manifolds with general affine connection. We extend the conformal transformation law of the metric to a general metric compatible affine connection, and find that it is a…

High Energy Physics - Theory · Physics 2016-12-07 Stefano Lucat , Tomislav Prokopec

In this work we examine the internal structure of compact stars within an extended gravitational framework described by the function $f(\mathcal{R},\mathcal{G},\mathcal{T})$. Throughout this work, the quantity $\mathcal{R}$ refers to the…

General Relativity and Quantum Cosmology · Physics 2025-11-25 G. G. L. Nashed

We consider $n$-dimensional asymptotically anti-de Sitter spacetimes in higher curvature gravitational theories with $n \geq 4$, by employing the conformal completion technique. We first argue that a condition on the Ricci tensor should be…

High Energy Physics - Theory · Physics 2009-11-11 Naoya Okuyama , Jun-ichirou Koga

We consider the Mielke-Baekler model of three-dimensional AdS gravity with torsion, which has gravitational and translational Chern-Simons terms in addition to the usual Einstein-Hilbert action with cosmological constant. It is shown that…

High Energy Physics - Theory · Physics 2008-11-26 Dietmar Klemm , Giovanni Tagliabue

We study canonical conformal gravity in four dimensions and construct the gauge generators and the associated charges. Using slightly generalized boundary conditions compared to those in \cite{Grumiller:2013mxa} we find that the charges…

High Energy Physics - Theory · Physics 2015-06-03 Maria Irakleidou , Iva Lovrekovic , Florian Preis

This is the second of three papers on Conformal General Relativity (CGR). The conformal group is introduced here as the invariance group of the partial order of causal events in $n$D spacetime. Its general structure, discrete symmetries and…

High Energy Physics - Theory · Physics 2016-03-28 Renato Nobili

We introduce a variation of the classical Ricci flow equation that modifies the unit volume constraint of that equation to a scalar curvature constraint. The resulting equations are named the Conformal Ricci Flow Equations because of the…

Differential Geometry · Mathematics 2009-11-10 Arthur E. Fischer

A 3D metric conformally related to Arnold cat fast dynamo metric: ${ds_{A}}^{2}=e^{-{\lambda}z}dp^{2}+e^{{\lambda}z}dq^{2}+dz^{2}$ is shown to present a behaviour of non-dynamos where the magnetic field exponentially decay in time. The…

Fluid Dynamics · Physics 2007-05-23 Garcia de Andrade

We present new non-Ricci-flat Kahler metrics with U(N) and O(N) isometries as target manifolds of superconformally invariant sigma models with an anomalous dimension. They are so-called Ricci solitons, special solutions to a Ricci-flow…

High Energy Physics - Theory · Physics 2007-05-23 Muneto Nitta

We investigate the conformal invariant Lagrangian of the self-gravitating U(1) scalar-gauge field and find new features of the model on the time-dependent axially symmetric Bondi-Marder spacetime. By considering the conformal symmetry as…

General Relativity and Quantum Cosmology · Physics 2018-11-06 Reinoud Jan Slagter

We give here a list of exact classical solutions of a large class of weakly nonlocal theories of gravity, which are unitary and super-renormalizable (or finite) at quantum level. It is explicitly shown that flat and Ricci-flat spacetimes as…

High Energy Physics - Theory · Physics 2016-01-27 Yao-Dong Li , Leonardo Modesto , Leslaw Rachwal

Alternative gravitational theories described by Lagrangians depending on general functions of the Ricci scalar have been proven to give coherent theoretical models to describe the experimental evidence of the acceleration of universe at…

High Energy Physics - Theory · Physics 2011-07-19 G. Allemandi , A. Borowiec , M. Francaviglia

The Janis-Newman-Winicour metric is a solution of Einstein's gravity minimally coupled to a real massless scalar field. The $\gamma$-metric is instead a vacuum solution of Einstein's gravity. These spacetimes have no horizon and possess a…

General Relativity and Quantum Cosmology · Physics 2018-03-08 Hrishikesh Chakrabarty , Carlos A. Benavides-Gallego , Cosimo Bambi , Leonardo Modesto

We consider the classic problem of a compact fluid source that behaves non-relativistically and that radiates gravitational waves. The problem consists of determining the metric close to the source as well as far away from it. The…

General Relativity and Quantum Cosmology · Physics 2024-02-05 Jelle Hartong , Jørgen Musaeus

Einstein's theory of general relativity is written in terms of the variables obtained from a conformal--traceless decomposition of the spatial metric and extrinsic curvature. The determinant of the conformal metric is not restricted, so the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 David Brown

In this work we elaborate on an extension of the AdS/CFT framework to a subclass of gravitational theories with vanishing cosmological constant. By building on earlier ideas, we construct a correspondence between Ricci-flat spacetimes…

High Energy Physics - Theory · Physics 2015-06-05 R. N. Caldeira Costa

We investigate the impact of conformal transformations on the physical properties of solution trajectories in nonmetricity gravity. Specifically, we explore the phase-space and reconstruct the cosmological history of a spatially flat…

General Relativity and Quantum Cosmology · Physics 2023-12-19 Nikolaos Dimakis , Kevin Duffy , Alex Giacomini , Alexander Yu. Kamenshchik , Genly Leon , Andronikos Paliathanasis

We consider higher dimensional gravity in which the four dimensional spacetime and extra dimensions are not treated on an equal footing. The anisotropy is implemented in the ADM decomposition of higher dimensional metric by requiring the…

High Energy Physics - Theory · Physics 2017-09-27 Taeyoon Moon , Phillial Oh