English
Related papers

Related papers: Quaternionic contact structures in dimension 7

200 papers

Given a quaternionic manifold $M$ with a certain $\mathrm{U}(1)$-symmetry, we construct a hypercomplex manifold $M'$ of the same dimension. This construction generalizes the quaternionic K\"ahler/hyper-K\"ahler-correspondence. As an example…

Differential Geometry · Mathematics 2019-04-15 Vicente Cortés , Kazuyuki Hasegawa

A conformal metric on a 4-ball induces on the boundary 3-sphere a conformal metric and a trace-free second fundamental form. Conversely, such a data on the 3-sphere is the boundary of a unique selfdual conformal metric, defined in a…

Differential Geometry · Mathematics 2007-05-23 Olivier Biquard

We call a quaternionic Kaehler manifold with non-zero scalar curvature, whose quaternionic structure is trivialized by a hypercomplex structure, a hyper-Hermitian quaternionic Kaehler manifold. We prove that every locally symmetric…

Differential Geometry · Mathematics 2007-05-23 Bogdan Alexandrov

We review the general properties of target spaces of hypermultiplets, which are quaternionic-like manifolds, and discuss the relations between these manifolds and their symmetry generators. We explicitly construct a one-to-one map between…

High Energy Physics - Theory · Physics 2009-11-10 Eric Bergshoeff , Sorin Cucu , Tim de Wit , Jos Gheerardyn , Stefan Vandoren , Antoine Van Proeyen

Co-oriented contact manifolds quite generally describe classical dynamical systems. Quantization is achieved by suitably associating a Schr\"odinger equation to every path in the contact manifold. We quantize the standard contact seven…

Symplectic Geometry · Mathematics 2025-07-22 Subhobrata Chatterjee , Can Görmez , Andrew Waldron

We derive some necessary conditions on a Riemannian metric $(M, g)$ in four dimensions for it to be locally conformal to K\"ahler. If the conformal curvature is non anti--self--dual, the self--dual Weyl spinor must be of algebraic type $D$…

Differential Geometry · Mathematics 2015-05-13 Maciej Dunajski , Paul Tod

We give an explicit formula for the quaternionic K\"ahler metrics obtained by the HK/QK correspondence. As an application, we give a new proof of the fact that the Ferrara-Sabharwal metric as well as its one-loop deformation is quaternionic…

Differential Geometry · Mathematics 2015-03-31 Dmitri V. Alekseevsky , Vicente Cortés , Malte Dyckmanns , Thomas Mohaupt

We interpret the property of having an infinitesimal symmetry as a variational property in certain geometric structures. This is achieved by establishing a one-to-one correspondence between a class of cone structures with an infinitesimal…

Differential Geometry · Mathematics 2026-04-03 Omid Makhmali , Katja Sagerschnig

In this note, we describe the geometry of the quaternionic Heisenberg groups from a Riemannian viewpoint. We show, in all dimensions, that they carry an almost $3$-contact metric structure which allows us to define the metric connection…

Differential Geometry · Mathematics 2015-10-28 Ilka Agricola , Ana Cristina Ferreira , Reinier Storm

A quaternionic K\"ahler manifold M is called {\it positive} if it has positive scalar curvature. The main purpose of this paper is to prove several connectedness theorems for quaternionic immersions in a quaternionic K\"ahler manifold, e.g.…

Differential Geometry · Mathematics 2007-05-23 Fuquan Fang

We describe explicitly all quaternionic contact hypersurfaces (qc-hypersurfaces) in the flat quaternion space $\Hnn$ and the quaternion projective space. We show that up to a quaternionic affine transformation a qc-hypersurface in $\Hnn$ is…

Differential Geometry · Mathematics 2014-06-18 Stefan Ivanov , Ivan Minchev , Dimiter Vassilev

We give explicit bijective correspondences between three families of objects: certain pairs of quaternions, which we regard as spinors; certain flags in (1+4)-dimensional Minkowski space; and horospheres in 4-dimensional hyperbolic space…

Geometric Topology · Mathematics 2025-04-03 Daniel V. Mathews , Varsha

A hypercomplex manifold $M$ is a manifold equipped with three complex structures satisfying quaternionic relations. Such a manifold admits a canonical torsion-free connection preserving the quaternion action, called Obata connection. A…

Differential Geometry · Mathematics 2018-06-08 Gueo Grantcharov , Mehdi Lejmi , Misha Verbitsky

A Kahler metric is said to be Bochner-Kahler if its Bochner curvature vanishes. This is a nontrivial condition when the complex dimension of the underlying manifold is at least 2. In this article it will be shown that, in a certain…

Differential Geometry · Mathematics 2007-05-23 Robert L. Bryant

We prove that the supergravity r- and c-maps preserve completeness. As a consequence, any component H of a hypersurface {h=1} defined by a homogeneous cubic polynomial such that -d^2 h is a complete Riemannian metric on H defines a complete…

High Energy Physics - Theory · Physics 2015-05-27 V. Cortes , T. Mohaupt , H. Xu

We study relations between quaternionic Riemannian manifolds admitting different types of symmetries. We show that any hyperKahler manifold admitting hyperKahler potential and triholomorphic action of S^1 can be constructed from another…

Differential Geometry · Mathematics 2009-11-13 Andriy Haydys

We answer in the affirmative a question posed by Ivanov and Vassilev on the existence of a seven dimensional quaternionic contact manifold with closed fundamental 4-form and non-vanishing torsion endomorphism. Moreover, we show an approach…

Differential Geometry · Mathematics 2014-05-12 Diego Conti , Marisa Fernández , José A. Santisteban

In this work we consider a class of contact manifolds $(M,\eta)$ with an associated almost contact metric structure $(\phi, \xi, \eta,g)$. This class contains, for example, nearly cosymplectic manifolds and the manifolds in the class…

Differential Geometry · Mathematics 2016-07-26 Eugenia Loiudice

The quantum Kepler-Coulomb system in 3 dimensions is well known to be 2nd order superintegrable, with a symmetry algebra that closes polynomially under commutators. This polynomial closure is also typical for 2nd order superintegrable…

Mathematical Physics · Physics 2015-06-11 E. G. Kalnins , J. M. Kress , W. Miller

In this note we study contact structures on 5-dimensional manifolds. We give a complete answer under the assumption that the Abundance conjecture holds in dimension 5.

Algebraic Geometry · Mathematics 2007-05-23 Stéphane Druel