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Related papers: Twistor Theory for co-CR quaternionic manifolds an…

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We give an overview of some recent results in hypersymplectic and para-quaternionic Kahler geometry, and introduce the notion of split three-Sasakian manifold. In particular, we discuss the twistor spaces and Swann bundles of…

Differential Geometry · Mathematics 2007-05-23 A. S. Dancer , H. R. Jorgensen , A. F. Swann

Scalar curvature invariants are studied in type N solutions of vacuum Einstein's equations with in general non-vanishing cosmological constant Lambda. Zero-order invariants which include only the metric and Weyl (Riemann) tensor either…

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. Bicak , V. Pravda

On base of differential biquaternions algebra and generalized functions theory the biquaternionic wave equation is considered under vector representation of its structural coefficient. Its generalized solutions are constructed, which…

Mathematical Physics · Physics 2014-06-23 L. A Alexeyeva

We describe special Ka\"hler geometry, special quaternionic manifolds, and very special real manifolds and analyze the structure of their isometries. The classification of the homogeneous manifolds of these types is presented.

High Energy Physics - Theory · Physics 2008-02-03 B. de Wit , A. Van Proeyen

We analyse in a systematic way the (non-)compact four dimensional Einstein-Weyl spaces equipped with a Bianchi metric. We show that Einstein-Weyl structures with a Class A Bianchi metric have a conformal scalar curvature of constant sign on…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Guy Bonneau

We investigate cosmological models in a recently proposed geometrical theory of gravity, in which the scalar field appears as part of the space-time geometry. We extend the previous theory to include a scalar potential in the action. We…

General Relativity and Quantum Cosmology · Physics 2016-09-14 M. L. Pucheu , F. A. P. Alves-Junior , A. B. Barreto , C. Romero

The purpose of the present paper is to study the differential geometric properties of a quaternion CR-submanifold in a locally conformal quaternion Kaehler manifold.

Differential Geometry · Mathematics 2007-08-10 Bayram Sahin

This is the first comprehensive introduction to the authors' recent attempts toward a better understanding of the global concepts behind spinor representations of surfaces in 3-space. The important new aspect is a quaternionic-valued…

Differential Geometry · Mathematics 2007-05-23 F. Burstall , D. Ferus , K. Leschke , F. Pedit , U. Pinkall

We show that a class of solutions of minimal supergravity in five dimensions is given by lifts of three--dimensional Einstein--Weyl structures of hyper-CR type. We characterise this class as most general near--horizon limits of…

High Energy Physics - Theory · Physics 2017-02-15 Maciej Dunajski , Jan Gutowski , Wafic Sabra

We show how the universal low-energy properties of Weyl semimetals with spatially varying time-reversal (TR) or inversion (I) symmetry breaking are described in terms of chiral fermions experiencing curved-\emph{spacetime} geometry and…

Mesoscale and Nanoscale Physics · Physics 2019-10-23 Long Liang , Teemu Ojanen

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 note, we prove a concrete variant of the twistor theorem of Hitchin--Karlhede--Lindstr\"om--Ro\v{c}ek which applies when one already has the real manifold on which one wishes to construct a hyper-K\"ahler structure, and so one does…

Differential Geometry · Mathematics 2025-01-03 Laura Fredrickson , Max Zimet

In this paper, we use four-dimensional quaternionic algebra to describing space-time field equations in curvature form. The transformation relations of a quaternionic variable are established with the help of basis transformations of…

General Physics · Physics 2024-10-08 B. C. Chanyal

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 twistor space of a Riemannian 4-manifold carries two almost complex structures, $J_+$ and $J_-$, and a natural closed 2-form $\omega$. This article studies limits of manifolds for which $\omega$ tames either $J_+$ or $J_-$. This amounts…

Differential Geometry · Mathematics 2017-05-04 Joel Fine

We derive variational formulas for the total Q-prime curvature under the deformation of strictly pseudoconvex domains in a complex manifold. We also show that the total Q-prime curvature agrees with the renormalized volume of such domains…

Differential Geometry · Mathematics 2016-11-22 Kengo Hirachi , Taiji Marugame , Yoshihiko Matsumoto

We determine the space of algebraic pseudo-Hermitian K\"ahler-Weyl curvature tensors and the space of para-Hermitian K\"ahler-Weyl curvature tensors in dimension 4 and show that every algebraic possibility is geometrically realizable. We…

Differential Geometry · Mathematics 2011-09-22 P. Gilkey , S. Nikcevic

Motivated by the analogies between the projective and the almost quaternionic geometries, we study the generalized planar curves and mappings. We follow, recover, and extend the classical approach as developed by Mikes and Sinyukov. Then we…

Differential Geometry · Mathematics 2007-05-23 Jaroslav Hrdina , Jan Slovak

In this paper we introduce paraquaternionic CR-submanifolds of almost paraquaternionic hermitian manifolds and state some basic results on their differential geometry. We also study a class of semi-Riemannian submersions from…

Differential Geometry · Mathematics 2010-07-13 Stere Ianus , Stefano Marchiafava , Gabriel Eduard Vilcu

Quantum $r$-Airy structures can be constructed as modules of $\mathcal{W}(\mathfrak{gl}_r)$-algebras via restriction of twisted modules for the underlying Heisenberg algebra. In this paper we classify all such higher quantum Airy structures…

Mathematical Physics · Physics 2023-06-22 Vincent Bouchard , Kieran Mastel