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The Weyl geometric gravity theory, in which the gravitational action is constructed from the square of the Weyl curvature scalar and the strength of the Weyl vector, has been intensively investigated recently. The theory admits a…

General Relativity and Quantum Cosmology · Physics 2025-11-19 Mohsen Khodadi , Tiberiu Harko

We investigate static, axially symmetric spacetimes without naked singularities that are constructed by patching Weyl class spacetimes with the flat spacetimes. Once the exterior geometry is specified, the junction conditions determine the…

General Relativity and Quantum Cosmology · Physics 2024-12-31 Daiki Saito , Daisuke Yoshida

Let $A$ be a commutative, associative algebra with unity over $\mathbb{C}$. Using the definition of global Weyl modules for the map superalgebras given by Calixto, Lemay, and Savage we explicitly describe the structure of certain quotients…

Representation Theory · Mathematics 2015-06-24 Irfan Bagci , Samuel Chamberlin

The space of null geodesics of a spacetime carries a canonical contact structure which has proved to be key in the discussion of causality in spacetimes. However, not much progress has been made on its nature and not many explicit…

Differential Geometry · Mathematics 2021-09-09 Adrià Marín-Salvador

Algebraic classification of higher dimensional, shear-free, twist-free, expanding (or non-expanding) spacetime is studied with the limit of $D\rightarrow\infty$. Similar to classification of any arbitrary dimension $D>4$, this spacetime is…

General Relativity and Quantum Cosmology · Physics 2023-09-07 Pınar Kirezli

The differential structure on the kappa-Minkowski spacetime from Jordanian twist of Weyl algebra is constructed, and it is shown to be closed in 4-dimensions in contrast to the conventional formulation. Based on this differential structure,…

High Energy Physics - Theory · Physics 2009-09-28 Jong-Geon Bu , Jae Hyung Yee , Hyeong-Chan Kim

It is shown that in the 4d Euclidean space there are two causal structures defined by the temporal field. One of them is well-known Minkowski spacetime. In this case the gravitational potential (the positive definite Riemann metric) and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ivanhoe B. Pestov , Bijan Saha

In 1918 Weyl introduced Weyl conformal geometry and its associated quadratic action which was the first gauge theory, of a spacetime symmetry, the Weyl gauge theory (of dilatations and Poincar\'e symmetry). The initial physical…

General Relativity and Quantum Cosmology · Physics 2026-04-10 D. M. Ghilencea

Weyl superconductors feature Weyl points at zero energy in the three-dimensional (3D) Brillouin zone and arc states that connect the projections of these Weyl points on the surface. We report that higher-order Weyl superconductors can be…

Mesoscale and Nanoscale Physics · Physics 2021-05-26 W. B. Rui , Song-Bo Zhang , Moritz M. Hirschmann , Andreas P. Schnyder , Björn Trauzettel , Z. D. Wang

A bilinear form on a possibly graded vector space $V$ defines a graded Poisson structure on its graded symmetric algebra together with a star product quantizing it. This gives a model for the Weyl algebra in an algebraic framework, only…

Quantum Algebra · Mathematics 2013-06-14 Stefan Waldmann

This paper is motivated by the non-linear stability problem for the expanding region of Kerr de Sitter cosmologies in the context of Einstein's equations with positive cosmological constant. We show that under dynamically realistic…

Analysis of PDEs · Mathematics 2021-03-03 Volker Schlue

We consider weighted parallel spinors in Lorentzian Weyl geometry in arbitrary dimensions, choosing the weight such that the integrability condition for the existence of such a spinor, implies the geometry to be Einstein-Weyl. We then use…

General Relativity and Quantum Cosmology · Physics 2011-11-16 P. Meessen , T. Ortín , A. Palomo-Lozano

In this work we consider perturbations of homogeneous and hypersurface orthogonal cosmological backgrounds with local rotational symmetry (LRS), using a method based on the 1 + 1 + 2 covariant split of spacetime. The backgrounds, of LRS…

General Relativity and Quantum Cosmology · Physics 2018-01-08 Michael Bradley , Mats Forsberg , Zoltán Keresztes

We investigate the Weyl space-time extension of general relativity (GR) for studying the FLRW cosmology through focusing and defocusing of the geodesic congruences. We have derived the equations of evolution for expansion, shear and…

General Relativity and Quantum Cosmology · Physics 2011-12-06 Radouane Gannouji , Hemwati Nandan , Naresh Dadhich

Spacetime with general linear vector distortion is introduced. Thus, the torsion and the nonmetricity of the affine connection are assumed to be proportional to a vector field (and not its derivatives). The resulting two-parameter family of…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Jose Beltrán Jiménez , Tomi S. Koivisto

Using the asymptotic form of the bulk Weyl tensor, we present an explicit approach that allows us to reconstruct exact four-dimensional Einstein spacetimes which are algebraically special with respect to Petrov's classification. If the…

High Energy Physics - Theory · Physics 2018-04-13 Jakob Gath , Ayan Mukhopadhyay , Anastasios C. Petkou , P. Marios Petropoulos , Konstantinos Siampos

The classical theory of Riemann ellipsoids is formulated naturally as a gauge theory based on a principal G-bundle ${\cal P}$. The structure group G=SO(3) is the vorticity group, and the bundle ${\cal P}=GL_+(3, R})$ is the connected…

Mathematical Physics · Physics 2009-09-25 G. Rosensteel , J. Troupe

We investigate the class of root systems $R$ obtained by extending an $A_1$-type irreducible root system by a free abelian group $G$. In this context there is a Weyl group $W$ and a group $U$ with the presentation by conjugation. Both…

Group Theory · Mathematics 2008-04-11 Georg W. Hofmann

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

We study the modular Hamiltonian associated with a Gaussian state on the Weyl algebra. We obtain necessary/sufficient criteria for the local equivalence of Gaussian states, independently of the classical results by Araki and Yamagami, Van…

Mathematical Physics · Physics 2023-03-23 Roberto Longo