English
Related papers

Related papers: Conformally flat FRW metrics

200 papers

We describe the general structure of the spherically symmetric solutions in the Weyl conformal gravity. The corresponding Bach equations are derived for the special type of metrics, which can be considered as the representative of the…

General Relativity and Quantum Cosmology · Physics 2016-04-21 V. A. Berezin , V. I. Dokuchaev , Yu. N. Eroshenko

We reexamine from first principles the classical Goldberg-Sachs theorem from General Relativity. We cast it into the form valid for complex metrics, as well as real metrics of any signature. We obtain the sharpest conditions on the…

Differential Geometry · Mathematics 2009-12-11 A Rod Gover , C Denson Hill , Pawel Nurowski

In this note we wish to complement some recent work in the cosmological literature concerning the Weyl conformal curvature tensor and its parts. In particular, we shall give a clear-cut definition of the Newtonian limits of electric and…

General Relativity and Quantum Cosmology · Physics 2009-08-23 Juergen Ehlers , Thomas Buchert

A metric projective structure is a manifold equipped with the unparametrised geodesics of some pseudo-Riemannian metric. We make acomprehensive treatment of such structures in the case that there is a projective Weyl curvature nullity…

Differential Geometry · Mathematics 2017-11-28 A. Rod Gover , Vladimir S. Matveev

We show that every Weyl module for a current algebra has a filtration whose successive quotients are isomorphic to Demazure modules, and that the path model for a tensor product of level zero fundamental representations is isomorphic to a…

Representation Theory · Mathematics 2012-10-02 Katsuyuki Naoi

A projective structure is Weyl metrizable if it has a representative that preserves a conformal structure. We interpret Weyl metrizability of 3-dimensional projective structures as certain 5-dimensional nondegenerate CR submanifolds in a…

Differential Geometry · Mathematics 2026-02-23 Omid Makhmali

In the first part of this article we revisit the theory of weighted spinors on conformal manifolds. In the second part we introduce the notions of asymptotically flat Weyl structures and of associated mass, and we prove a conformal version…

Differential Geometry · Mathematics 2008-10-15 Guillaume Vassal

In this paper we give an extensive description of Weyl quadratic gravity as the gauge theory of the Weyl group. The previously discovered (vectorial) torsion/non-metricity equivalence is shown to be built-in as it corresponds to a…

High Energy Physics - Theory · Physics 2025-02-25 Cezar Condeescu , Andrei Micu

We prove the existence of compact pseudo-Riemannian manifolds with parallel Weyl tensor which are neither conformally flat nor locally symmetric, and represent all indefinite metric signatures in all dimensions $\,n\ge5$. Until now such…

Differential Geometry · Mathematics 2023-10-03 Andrzej Derdzinski , Ivo Terek

In Finsler geometry, there are infinitely many models of constant curvature. The Funk metrics, the Hilbert-Klein metrics and the Bryant metrics are projectively flat with non-zero constant curvature. A recent example constructed by the…

Differential Geometry · Mathematics 2007-05-23 Zhongmin Shen

A new class of conformal field theories is presented, where the background gravitational field is conformally flat. Conformally flat (CF) spacetimes enjoy conformal properties quite similar to the ones of flat spacetime. The conformal…

High Energy Physics - Theory · Physics 2020-07-01 Enrique Alvarez , Raquel Santos-Garcia

The conformal Fefferman-Graham ambient metric construction is one of the most fundamental constructions in conformal geometry. It embeds a manifold with a conformal structure into a pseudo-Riemannian manifold whose Ricci tensor vanishes up…

Differential Geometry · Mathematics 2024-12-02 Ian M Anderson , Thomas Leistner , Andree Lischewski , Pawel Nurowski

All possible transformations from the Robertson-Walker metric to those conformal to the Lorentz-Minkowski form are derived. It is demonstrated that the commonly known family of transformations and associated conformal factors are not…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Ibison

Conformal geometry is studied using the unfolded formulation \`a la Vasiliev. Analyzing the first-order consistency of the unfolded equations, we identify the content of zero-forms as the spin-two off-shell Fradkin-Tseytlin module of…

High Energy Physics - Theory · Physics 2022-01-05 Euihun Joung , Min-gi Kim , Yujin Kim

We compute the noncommutative deformations of a family of modules over the first Weyl algebra. This example shows some important properties of noncommutative deformation theory that separates it from commutative deformation theory.

Algebraic Geometry · Mathematics 2007-12-14 Eivind Eriksen

A new method for the construction of conformally invariant equations in an arbitrary four dimensional (pseudo-) Riemannian space is presented. This method uses the Weyl geometry as a tool and exploits the natural conformal invariance we can…

High Energy Physics - Theory · Physics 2015-12-01 Sofiane Faci

We argue that conformal invariance in flat spacetime implies Weyl invariance in a general curved background metric for all unitary theories in spacetime dimensions $d \leq 10$. We also study possible curvature corrections to the Weyl…

High Energy Physics - Theory · Physics 2017-11-22 Kara Farnsworth , Markus A. Luty , Valentina Prilepina

This is a final step in a local classification of pseudo-Riemannian manifolds with parallel Weyl tensor that are not conformally flat or locally symmetric.

Differential Geometry · Mathematics 2009-03-06 Andrzej Derdzinski , Witold Roter

We present a geometric construction and characterization of $2n$-dimensional split-signature conformal structures endowed with a twistor spinor with integrable kernel. The construction is regarded as a modification of the conformal…

Differential Geometry · Mathematics 2023-01-12 Matthias Hammerl , Katja Sagerschnig , Josef Šilhan , Vojtěch Žádník

We study Kahler surfaces with harmonic anti-selfdual Weyl tensor. We provide an explicit local description, which we use to obtain the complete classification in the compact case. We give new examples of extremal Kahler metrics, including…

Differential Geometry · Mathematics 2007-05-23 Vestislav Apostolov , David M. J. Calderbank , Paul Gauduchon