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Related papers: On nearly Kaehler geometry

200 papers

We prove that every projective special K\"ahler manifold with \emph{regular boundary behaviour} is complete and defines a family of complete quaternionic K\"ahler manifolds depending on a parameter $c\ge 0$. We also show that, irrespective…

Differential Geometry · Mathematics 2016-12-30 Vicente Cortés , Malte Dyckmanns , Stefan Suhr

In this work we prove that any unitary Sobolev $W^{1,2}$ connection of an Hermitian bundle over a 2-dimensional K\"ahler manifold whose curvature is $(1,1)$ defines a smooth holomorphic structure. We prove moreover that such a connection…

Differential Geometry · Mathematics 2019-10-30 Alexandru Paunoiu , Tristan Rivière

Let H be a 4 dimensional almost Hermitian manifold which satisfies the Kaehler identity. Then H is complex Osserman if and only if H has constant holomorphic sectional curvature. We also classify in arbitrary dimensions all the complex…

Differential Geometry · Mathematics 2010-03-30 Miguel Brozos-Vazquez , Peter Gilkey

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 investigate the integrability of almost complex structures on the twistor space of an almost quaternionic manifold constructed with the help of a quaternionic connection. We show that if there is an integrable structure it is independent…

Differential Geometry · Mathematics 2007-05-23 Stefan Ivanov , Ivan Minchev , Simeon Zamkovoy

We find that the target space of two-dimensional (4,0) supersymmetric sigma models with torsion coupled to (4,0) supergravity is a QKT manifold, that is, a quaternionic K\"ahler manifold with torsion. We give four examples of geodesically…

High Energy Physics - Theory · Physics 2009-10-09 P. S. Howe , A. Opfermann , G. Papadopoulos

It is proved that if an almost K\"ahler manifold of dimension greater or equal to 8 is of pointwise constant antiholomorphic sectional curvature, then it is a complex space form.

Differential Geometry · Mathematics 2010-10-08 Maria Falcitelli , Angela Farinola , Ognian Kassabov

The authors define a SNS (semi-nearly-sub)-Riemannian connection on nearly sub-Riemannian manifolds and study the geometric properties of such a connection, and obtain the natures of horizontal curvature tensors between horizontal…

Differential Geometry · Mathematics 2016-01-25 Yanling Han , Peibiao Zhao

In this article, we examine the behavior of the Riemannian and Hermitian curvature tensors of a Hermitian metric, when one of the curvature tensors obeys all the symmetry conditions of the curvature tensor of a K\"ahler metric. We will call…

Differential Geometry · Mathematics 2023-03-31 Bo Yang , Fangyang Zheng

Classification results for complex Riemannian foliations are obtained. For open subsets of irreducible Hermitian symmetric spaces of compact type, where one has explicit control over the curvature tensor, we completely classify such…

Differential Geometry · Mathematics 2019-05-07 Thomas Murphy , Paul-Andi Nagy

We show that a Hermitian algebraic curvature model satisfies the Gray identity if and only if it is geometrically realizable by a Hermitian manifold. Furthermore, such a curvature model can in fact be realized by a Hermitian manifold of…

Differential Geometry · Mathematics 2008-12-16 M. Brozos-Vazquez , P. Gilkey , H. Kang , S. Nikcevic

This paper is concerned with the existence of metrics of constant Hermitian scalar curvature on almost-K\"ahler manifolds obtained as smoothings of a constant scalar curvature K\"ahler orbifold, with $A_1$ singularities. More precisely,…

Differential Geometry · Mathematics 2018-06-21 Caroline Vernier

The twistor space \Z of an oriented Riemannian 4-manifold M admits a natural 1-parameter family of Riemannian metrics h_t compatible with the almost complex structures J_1 and J_2 introduced, respectively, by Atiyah, Hitchin and Singer, and…

Differential Geometry · Mathematics 2007-05-23 J. Davidov , G. Grantcharov , O. Muskarov

We prove that any Kaehler manifold admitting a flat complex conformal connection is a Bochner-Kaehler manifold with special scalar distribution and zero geometric constants. Applying the local structural theorem for such manifolds we obtain…

Differential Geometry · Mathematics 2007-06-07 Georgi Ganchev , Vesselka Mihova

In a recent work, Kai Tang conjectured that any compact Hermitian manifold with non-zero constant mixed curvature must be K\"ahler. He confirmed the conjecture in complex dimension $2$ and for Chern K\"ahler-like manifolds in general…

Differential Geometry · Mathematics 2025-10-14 Shuwen Chen , Fangyang Zheng

In this survey, we give an introduction to nearly K\"ahler geometry, and list some results on submanifolds of these spaces. This survey tries by no means to be complete.

Differential Geometry · Mathematics 2024-01-11 Mateo Anarella

We complete the classification of compact Hermitian manifolds admitting a flat Gauduchon connection. In particular, we establish a conjecture of Yang and Zheng, showing that apart from the cases of a flat Chern or Bismut connection, such…

Differential Geometry · Mathematics 2022-07-20 Ramiro A. Lafuente , James Stanfield

A hypercomplex manifold is by definition a smooth manifold equipped with two anticommuting integrable almost complex structures. For example, every hyperkaehler manifold is canonically hypercomplex (the converse is not true). For every…

alg-geom · Mathematics 2008-02-03 D. Kaledin

For complete complex connections on almost complex manifolds we introduce a natural definition of compactification. This is based on almost c--projective geometry, which is the almost complex analogue of projective differential geometry.…

Differential Geometry · Mathematics 2019-10-31 Andreas Cap , A. Rod Gover

There are studied in details 5-dimensional pseudo-Riemannian manifolds equipped with the structure analogous to the almost cosymplectic (almost coKaehler) structure. The curvature by assumption commutes with the structure affinor and all…

Differential Geometry · Mathematics 2013-08-30 Piotr Dacko