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Related papers: On Walker and para-Hermite Einstein spaces

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We consider isolated horizons (Killing horizons up to the second order) whose null flow has the structure of a U(1) principal fiber bundle over a compact Riemann surface. We impose the vacuum Einstein equations (with the cosmological…

General Relativity and Quantum Cosmology · Physics 2024-08-16 Jerzy Lewandowski , Maciej Ossowski

Einstein-Weyl geometry is a triple (D,g,w), where D is a symmetric connection, [g] is a conformal structure and w is a covector such that: (i) connection D preserves the conformal class [g], that is, Dg=wg; (ii) trace-free part of the…

Exactly Solvable and Integrable Systems · Physics 2022-06-29 Sobhi Berjawi , Eugene Ferapontov , Boris Kruglikov , Vladimir Novikov

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 develop a dimension-independent theory of alignment in Lorentzian geometry, and apply it to the tensor classification problem for the Weyl and Ricci tensors. First, we show that the alignment condition is equivalent to the PND equation.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 R. Milson , A. Coley , V. Pravda , A. Pravdova

Eigenfunctions are shown to constitute privileged coordinates of self-dual Einstein spaces with the underlying governing equation being revealed as the general heavenly equation. The formalism developed here may be used to link…

Exactly Solvable and Integrable Systems · Physics 2021-02-03 B. G. Konopelchenko , W. K. Schief , A. Szereszewski

We consider four-dimensional, Riemannian, Ricci-flat metrics for which one or other of the self-dual or anti-self-dual Weyl tensors is type-D. Such metrics always have a valence-2 Killing spinor, and therefore a Hermitian structure and at…

General Relativity and Quantum Cosmology · Physics 2021-10-28 Paul Tod

The peeling behaviour of the Weyl tensor near null infinity is determined for an asymptotically flat higher dimensional spacetime. The result is qualitatively different from the peeling property in 4d. To leading order, the Weyl tensor is…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Mahdi Godazgar , Harvey S. Reall

This paper conducts a geometric analysis of the Joint-Eigenspace Fourier transform of the symmetric space of the non-compact type. Our study shows how the Poisson transform builds up the well-known Helgason Fourier transform for an analysis…

Functional Analysis · Mathematics 2024-09-17 Olufemi O. Oyadare

We determine the general form of the solutions of the five-dimensional vacuum Einstein equations with cosmological constant for which (i) the Weyl tensor is everywhere type II or more special in the null alignment classification of Coley et…

General Relativity and Quantum Cosmology · Physics 2016-04-27 Gabriel Bernardi de Freitas , Mahdi Godazgar , Harvey S. Reall

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

We derive a superpotential for null electromagnetic fields in which the field line structure is in the form of an arbitrary torus knot. These fields are shown to correspond to single copies of a class of anti-self-dual Kerr-Schild…

High Energy Physics - Theory · Physics 2019-07-15 Snigdh Sabharwal , Jan Willem Dalhuisen

We embed the Penrose limit into the Weyl classical double copy. Thereby, we provide a lift of the double copy properties of plane wave spacetimes into black hole geometries and we open a novel avenue towards taking the classical double copy…

High Energy Physics - Theory · Physics 2024-07-12 Samarth Chawla , Kwinten Fransen , Cynthia Keeler

An exhaustive list of four-dimensional $\Lambda$-vacuum spacetimes admitting a Killing vector whose self-dual Killing two-form ${\cal F}$ is null is obtained assuming that the self-dual Weyl tensor is proportional to the tensor product of…

General Relativity and Quantum Cosmology · Physics 2016-09-21 Marc Mars , José M. M. Senovilla

The Newman-Penrose map, which is closely related to the classical double copy, associates certain exact solutions of Einstein's equations with self-dual solutions of the vacuum Maxwell equations. Here we initiate an extension of the…

High Energy Physics - Theory · Physics 2023-09-20 Kara Farnsworth , Michael Graesser , Gabriel Herczeg

The images of Hermite and Laguerre Sobolev spaces under the Hermite and special Hermite semigroups (respectively) are characterised. These are used to characterise the Schwartz class of rapidly decreasing functions. The image of the space…

Functional Analysis · Mathematics 2007-10-19 R. Radha , S. Thangavelu

This paper gives an analogue to the classical Schur-Weyl duality in the setting of Deligne categories. Given a finite-dimensional unital vector space V (i.e. a vector space V with a distinguished non-zero vector 1), we give a definition of…

Representation Theory · Mathematics 2017-06-19 Inna Entova-Aizenbud

We study the class of six-dimensional $\Lambda$-vacuum spacetimes which admit a non-degenerate multiple Weyl aligned null direction l (thus being of Weyl type~II or more special) with a ``generic'' optical matrix. Subject to an additional…

General Relativity and Quantum Cosmology · Physics 2025-08-29 David Kokoška , Marcello Ortaggio

The author has elsewhere given a complete classification of those compact oriented Einstein 4-manifolds on which the self-dual Weyl curvature is everywhere positive in the direction of some self-dual harmonic 2-form. In this article,…

Differential Geometry · Mathematics 2019-03-26 Claude LeBrun

We study a class of higher dimensional warped Einstein spacetimes with one extra dimension. These were originally identified by Brinkmann as those Einstein spacetimes that can be mapped conformally on other Einstein spacetimes, and have…

General Relativity and Quantum Cosmology · Physics 2011-04-08 Marcello Ortaggio , Vojtech Pravda , Alena Pravdova

We give a complete proof of the result stated in an earlier article, that the general Einstein metric with a symmetry, an anti-self-dual Weyl tensor and nonzero scalar curvature is determined by a solution of the $SU(\infty)$-Toda field…

High Energy Physics - Theory · Physics 2007-05-23 Paul Tod