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The space of tensors of metric curvature type on a Euclidean vector space carries a two-parameter family of orthogonally invariant commutative nonassociative multiplications invariant with respect to the symmetric bilinear form determined…

Rings and Algebras · Mathematics 2023-06-22 Daniel J. F. Fox

We consider the problem of finding complete conformal metrics with prescribed curvature functions of the Einstein tensor and of more general modified Schouten tensors. To achieve this, we reveal an algebraic structure of a wide class of…

Differential Geometry · Mathematics 2021-05-04 Rirong Yuan

The condition for the vanishing of the Weyl tensor is integrated in the spherically symmetric case. Then, the resulting expression is used to find new, conformally flat, interior solutions to Einstein equations for locally anisotropic…

General Relativity and Quantum Cosmology · Physics 2015-06-25 L. Herrera , A. Di Prisco , J. Ospino , E. Fuenmayor

In this paper, we study locally strongly convex affine hypersurfaces with vanishing Weyl curvature tensor and semi-parallel cubic form relative to the Levi-Civita connection of affine metric. As the main result, we classify such…

Differential Geometry · Mathematics 2024-02-21 Huiyang Xu , Cece Li

A piecewise flat manifold is a triangulated manifold given a geometry by specifying edge lengths (lengths of 1-simplices) and specifying that all simplices are Euclidean. We consider the variation of angles of piecewise flat manifolds as…

Differential Geometry · Mathematics 2015-10-22 David Glickenstein

Motivated by the study of Weyl structures on conformal manifolds admitting parallel weightless forms, we define the notion of conformal product of conformal structures and study its basic properties. We obtain a classification of Weyl…

Differential Geometry · Mathematics 2019-01-08 Florin Belgun , Andrei Moroianu

Though the Weyl tensor is a linear combination of the curvature tensor, Ricci tensor and Ricci scalar, it does not have all and only the Lie symmetries of these tensors since it is possible, in principle, that "asymmetries cancel". Here we…

General Relativity and Quantum Cosmology · Physics 2009-01-09 Ibrar Hussain , Asghar Qadir , K. Saifullah

Weyl's conformal theory of gravity is an extension of Einstein's theory of general relativity which associates metrics with 1-forms . In the case of locally integrable (closed non-exact) 1-forms the spacetime manifolds are no more simply…

General Relativity and Quantum Cosmology · Physics 2022-06-09 Michel Duneau

The conformal properties of metrics are meaningful in Riemannian and Finsler geometry, and cubic metrics are useful in physics and biology. In this paper, we study the conformally flat cubic metrics with weakly isotropic scalar curvature.…

Differential Geometry · Mathematics 2023-09-04 Cuiling Ma , Xiaoling Zhang

In this note, we evaluate the Weyl-invariant quadratic curvature tensors for the particular Weyl's gauge field constructed in the $3+1$-dimensional noncompact Weyl-Einstein-Yang-Mills model. We subsequently extend the model to its higher…

High Energy Physics - Theory · Physics 2018-02-14 Suat Dengiz

The equations of General Relativity are recast in the form of a wave equation for the Weyl tensor. This allows to reformulate gravitational wave theory in terms of curvature waves, rather than metric waves. The existence of two transverse…

General Relativity and Quantum Cosmology · Physics 2023-02-21 Jan W. van Holten

A new 8-dim conformal gauging solves the auxiliary field problem and eliminates unphysical size change from Weyl's electromagnetic theory. We derive the Maurer-Cartan structure equations and find the zero curvature solutions for the…

High Energy Physics - Theory · Physics 2009-10-30 James T. Wheeler

We show any Weyl curvature model can be geometrically realized by a Weyl manifold

Differential Geometry · Mathematics 2010-11-23 Peter Gilkey , Stana Nikcevic , Udo Simon

We study complex 4-manifolds with holomorphic self-dual conformal structures, and we obtain an interpretation of the Weyl tensor of such a manifold as the projective curvature of a field of cones on the ambitwistor space. In particular, its…

Differential Geometry · Mathematics 2007-05-23 F. A. Belgun

We use certain Morse functions to construct conformal metrics with negative sectional curvature on locally conformally flat manifolds with boundary. Moreover, without conformally flatness assumption, we also construct conformal metric of…

Differential Geometry · Mathematics 2025-10-21 Rirong Yuan

We study substructures of the Weyl group of conformal transformations of the metric of (pseudo)Riemannian manifolds. These substructures are identified by differential constraints on the conformal factors of the transformations which are…

High Energy Physics - Theory · Physics 2024-07-10 Riccardo Martini , Gregorio Paci , Dario Sauro , Gian Paolo Vacca , Omar Zanusso

The development of projective invariant Weyl metrics in this paper offers a fresh perspective, as we establish the characteristics of both weakly-Weyl and generalized weakly-Weyl Finsler metrics. We thoroughly examine the connections…

Differential Geometry · Mathematics 2025-11-11 Nasrin Sadeghzadeh , Meshkat Yavari

Let (M,g) a compact Riemannian $n$-dimensional manifold with umbilic boundary. It is well know that, under certain hypothesis, in the conformal class of g there are scalar-flat metrics that have the boundary of M as a constant mean…

Differential Geometry · Mathematics 2020-09-03 Marco G. Ghimenti , Anna Maria Micheletti

Despite the fact that General Relativity (GR) has been very successful, many alternative theories of gravity have attracted the attention of a significant number of theoretical physicists. Among these theories, we have theories with…

General Relativity and Quantum Cosmology · Physics 2019-05-14 J. B. Formiga

We present a new formulation for the canonical approach to conformal (Weyl-squared) gravity and its extension by the Einstein-Hilbert term and a nonminimally coupled scalar field. For this purpose we use a unimodular decomposition of the…

General Relativity and Quantum Cosmology · Physics 2017-04-19 Claus Kiefer , Branislav Nikolic