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Related papers: Conformally flat FRW metrics

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This article is a survey of results involving conformal deformation of Riemannian metrics and fully nonlinear equations.

Differential Geometry · Mathematics 2007-05-23 Jeff Viaclovsky

We define a Weyl-type curvature tensor that provides a characterisation for Finsler metrics of constant flag curvature. When the Finsler metric reduces to a Riemannian metric, the Weyl-type curvature tensor reduces to the classic projective…

Differential Geometry · Mathematics 2020-02-04 Ioan Bucataru , Georgeta Creţu

According to [8] if the stationary Schroedinger equation on n-dim. Riemann space admits R-separation of variables (i.e. separation of variables with a factor R), then the underlying metric is necessarily isothermic. An important sub-class…

Mathematical Physics · Physics 2013-05-16 Adam Szereszewski , Antoni Sym

The problem of characterizing conformally Einstein manifolds by tensorial conditions has been tackled recently in papers by M. Listing, and in work by A. R. Gover and P. Nurowski. Their results apply to metrics satisfying a "non-degeneracy"…

Differential Geometry · Mathematics 2007-05-23 Jesse Alt

We have solved the Einstein equations of general relativity for a class of metrics with constant spatial curvature and found a non-vanishing Weyl tensor in the presence of an energy-momentum tensor with an anisotropic pressure component.…

General Physics · Physics 2013-09-18 E. Bittencourt , J. M. Salim

In this paper a thorough study of the normal form and the first integrability conditions arising from {\em bi-conformal vector fields} is presented. These new symmetry transformations were introduced in {\em Class. Quantum…

Mathematical Physics · Physics 2016-08-16 Alfonso García-Parrado Gómez-Lobo

By using a certain second order differential equation, the notion of adapted coordinates on Finsler manifolds is defined and some classifications of complete Finsler manifolds are found. Some examples of Finsler metrics, with positive…

Differential Geometry · Mathematics 2008-12-19 A. Asanjarani , B. Bidabad

It is well-known that the conformal structure of a relativistic spacetime is of profound physical and conceptual interest. In this note, we consider the analogous structure for Newtonian theories. We show that the Newtonian Weyl tensor is…

General Relativity and Quantum Cosmology · Physics 2020-10-28 Neil Dewar , James Read

An eight-parametric family of complex connections on a class complex manifolds with Norden metric is introduced. The form of the curvature tensor with respect to each of these connections is obtained. The conformal group of the considered…

Differential Geometry · Mathematics 2011-04-29 Marta Teofilova

In this paper, we give a new generalization of positive sectional curvature called positive weighted sectional curvature. It depends on a choice of Riemannian metric and a smooth vector field. We give several simple examples of Riemannian…

Differential Geometry · Mathematics 2014-10-08 Lee Kennard , William Wylie

We derive all possible causality conditions for conformally flat Lorentzian metrics on the two-dimensional cylinder.

Differential Geometry · Mathematics 2011-04-01 Alexander Dirmeier

Conformal symmetries appear in many parts of physics and play a unique role in exploring the Universe. In this work, we consider the possibility of constructing conformal theories of gravity in the Symmetric Teleparallel Gravity framework,…

General Relativity and Quantum Cosmology · Physics 2020-03-18 Viktor Gakis , Martin Krššák , Jackson Levi Said , Emmanuel N. Saridakis

Warped conformal field theories (WCFTs) are a novel class of non-relativistic theories. A simple, yet non-trivial, example of such theory is a massive Weyl fermion in $(1+1)$-dimensions, which we study in detail. We derive general…

High Energy Physics - Theory · Physics 2015-11-23 Alejandra Castro , Diego M. Hofman , Gábor Sárosi

We present a complete algebraic classification for the curvature tensor in Weyl-Cartan geometry, by applying methods of eigenvalues and principal null directions on its irreducible decomposition under the group of global Lorentz…

General Relativity and Quantum Cosmology · Physics 2023-08-24 Sebastian Bahamonde , Jorge Gigante Valcarcel

We investigate the geometry of a twisting non-shearing congruence of null geodesics on a conformal manifold of even dimension greater than four and Lorentzian signature. We give a necessary and sufficient condition on the Weyl tensor for…

Differential Geometry · Mathematics 2021-09-01 Arman Taghavi-Chabert

We consider the curvature of a family of warped products of two pseduo-Riemannian manifolds $(B,g_B)$ and $(F,g_F)$ furnished with metrics of the form $c^{2}g_B \oplus w^2 g_F$ and, in particular, of the type $w^{2 \mu}g_B \oplus w^2 g_F$,…

Differential Geometry · Mathematics 2008-11-26 Fernando Dobarro , Bulent Unal

We reconsider a gauge theory of gravity in which the gauge group is the conformal group SO(4,2) and the action is of the Yang-Mills form, quadratic in the curvature. The resulting gravitational theory exhibits local conformal symmetry and…

General Relativity and Quantum Cosmology · Physics 2016-04-07 Jack Gegenberg , Shohreh Rahmati , Sanjeev S. Seahra

We revisit Weyl's metrication (geometrization) of electromagnetism. We show that by making Weyl's proposed geometric connection be pure imaginary, not only are we able to metricate electromagnetism, an underlying local conformal invariance…

General Relativity and Quantum Cosmology · Physics 2016-11-15 Philip D. Mannheim

This paper gives new insights into the class of Generalized Douglas Weyl ($GDW$)-metrics. This projective invariant class of Finsler metrics, contains some well-known Finsler metrics such as Douglas, Weyl and $R$-quadratic metrics. Here,…

Differential Geometry · Mathematics 2025-11-10 Nasrin Sadeghzadeh , Najmeh Sajjadi Moghadam

We study Weyl conformal geometry as a general gauge theory of the Weyl group (of Poincar\'e and dilatations symmetries) in a manifestly Weyl gauge covariant formalism in which this geometry is automatically metric and physically relevant.…

High Energy Physics - Theory · Physics 2025-03-31 C. Condeescu , D. M. Ghilencea , A. Micu