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Related papers: Flat nearly K\"ahler manifolds

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Polyhedral K\"ahler surfaces are a class of complex surfaces, which are flat everywhere except on a two-dimensional skeleton. They are defined as a generalisation of the "gluing a polygon side by side" construction of flat Riemann surfaces.…

Algebraic Geometry · Mathematics 2018-06-11 Cécile Gachet

Let M be a compact Riemannian manifold equipped with a parallel differential form \omega. We prove a version of Kaehler identities in this setting. This is used to show that the de Rham algebra of M is weakly equivalent to its subquotient…

Differential Geometry · Mathematics 2011-03-02 Misha Verbitsky

We continue the program of Chinea, De Leon and Marrero who studied the topology of cosymplectic manifolds. We study 3-cosymplectic manifolds which are the closest odd-dimensional analogue of hyper-Kaehler structures. We show that there is…

Differential Geometry · Mathematics 2013-02-27 Beniamino Cappelletti Montano , Antonio De Nicola , Ivan Yudin

We study a sequence of connections which is associated with a Riemannian metric and an almost symplectic structure on a manifold. We prove that if this sequence is trivial (i.e. constant) or 2-periodic, then the manifold has a canonical…

Differential Geometry · Mathematics 2007-05-23 Mikhail Shubin

In this paper we discuss the geometry of homogeneous spaces witch are almost Hermitian submanifolds of flag manifolds. We prove that such spaces are necessarily minimal submanifolds and in the case where these submanifolds are also flag…

Differential Geometry · Mathematics 2024-06-19 Neiton Pereira da Silva

Let M be an almost complex manifold equipped with a Hermitian form such that its de Rham differential has Hodge type (3,0)+(0,3), for example a nearly Kahler manifold. We prove that any connected component of the moduli space of…

Differential Geometry · Mathematics 2013-10-28 Misha Verbitsky

In the paper there are described new examples of conformally flat three dimensional almost cosymplectic manifolds. All these manifolds form a class which was completely characterized.

Differential Geometry · Mathematics 2007-10-05 Piotr Dacko

We are interested in the question of the existence of flat manifolds for which all $\mathbb R$-irreducible components of the holonomy representation are either absolutely irreducible, of complex or of quaternionic type. In the first two…

Group Theory · Mathematics 2020-02-19 Gerhard Hiss , Rafał Lutowski , Andrzej Szczepański

Let $(M,J)$ be a $2n$-dimensional almost complex manifold and let $x\in M$. We define the notion of almost complex blow-up of $(M,J)$ at $x$. We prove the existence of almost complex blow-ups at $x$ under suitable assumptions on the almost…

Differential Geometry · Mathematics 2023-05-18 Richard Hind , Tommaso Sferruzza , Adriano Tomassini

The object of the present paper is to study 3-dimensional conformally flat quasi-Para-Sasakian manifolds. First, the necessary and sufficient conditions are provided for 3-dimensional quasi-Para-Sasakian manifolds to be conformally flat.…

Differential Geometry · Mathematics 2018-07-17 Irem Kupeli Erken

On an almost complex manifold $(M,J)$, a pluricanonical locally conformally almost K\"ahler (LCAK) metric $g$ is induced by a locally conformally symplectic structure $(F,\theta)$ of the first kind, characterized by the fact that $D\theta$…

Differential Geometry · Mathematics 2026-03-30 Ethan Addison , Tedi Draghici , Mehdi Lejmi

In this article we introduce the notion of Polyhedral Kahler manifolds, even dimensional polyhedral manifolds with unitary holonomy. We concentrate on the 4-dimensional case, prove that such manifolds are smooth complex surfaces, and…

Differential Geometry · Mathematics 2016-08-04 Dmitri Panov

A 3-parametric family of 6-dimensional quasi-Kaehler manifolds with Norden metric is constructed on a Lie group. This family is characterized geometrically. The condition for such a 6-manifold to be isotropic Kaehler is given.

Differential Geometry · Mathematics 2012-05-08 Mancho Manev , Kostadin Gribachev , Dimitar Mekerov

We classify, up to a local isometry, all non-Kahler almost Kahler 4-manifolds for which the fundamental 2-form is an eigenform of the Weyl tensor, and whose Ricci tensor is invariant with respect to the almost complex structure.…

Differential Geometry · Mathematics 2007-05-23 Vestislav Apostolov , John Armstrong , Tedi Draghici

We study the K\"ahler geometry of stage n Bott manifolds, which can be viewed as $n$-dimensional generalizations of Hirzebruch surfaces. We show, using a simple induction argument and the generalized Calabi construction from…

Differential Geometry · Mathematics 2020-12-17 Charles P. Boyer , David M. J. Calderbank , Christina W. Tønnesen-Friedman

In this note, we address the following question: Which 1-formal groups occur as fundamental groups of both quasi-K\"ahler manifolds and closed, connected, orientable 3-manifolds. We classify all such groups, at the level of Malcev…

Algebraic Geometry · Mathematics 2011-11-22 Alexandru Dimca , Stefan Papadima , Alexander I. Suciu

Given a semi-Riemannian $4$-manifold $(M,g)$ with two distinguished vector fields satisfying properties determined by their shear, twist and various Lie bracket relations, a family of K\"ahler metrics $g_K$ is constructed, defined on an…

Differential Geometry · Mathematics 2020-12-23 Amir Babak Aazami , Gideon Maschler

For k at least 2, we exhibit complete k-curvature homogeneous neutral signature pseudo-Riemannian manifolds which are not locally affine homogeneous (and hence not locally homogeneous). The curvature tensor of these manifolds is modeled on…

Differential Geometry · Mathematics 2007-05-23 Peter Gilkey , Stana Nikcevic

In this paper, we initiate the study of $\p R$-warped products in para-K\"ahler manifolds and prove some fundamental results on such submanifolds. In particular, we establish a general optimal inequality for $\p R$-warped products in…

Differential Geometry · Mathematics 2011-06-21 Bang-Yen Chen , Marian Ioan Munteanu

We extend the notion of an almost flat bundle over a closed Riemannian manifold to bundles over simplicial complexes, and prove that up to a constant factor, this notion is invariant under pullback via maps which induce isomorphisms on…

Geometric Topology · Mathematics 2018-03-15 Benedikt Hunger