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Related papers: Deformations of Nearly K\"{a}hler Structures

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We study Rarita-Schwinger fields on 6-dimensional compact strict nearly K\"{a}hler manifolds. In order to investigate them, we clarify the relationship between some differential operators for the Hermitian connection and the Levi-Civita…

Differential Geometry · Mathematics 2021-05-25 Soma Ohno , Takuma Tomihisa

Given a compact Kaehler manifold, we consider the complement U of a divisor with normal crossings. We study the variety of unitary representations of the fundamental group of U with certain restrictions related to the divisor. We show that…

dg-ga · Mathematics 2008-02-03 Philip A. Foth

We characterize compact locally conformally K\"ahler (l.c.K.) manifolds under the assumption of a purely conformal, holomorphic circle action. As an application, we determine the structure of the compact l.c.K. manifolds with parallel Lee…

Differential Geometry · Mathematics 2007-05-23 Yoshinobu Kamishima , Liviu Ornea

Let $(M,I)$ be an almost complex 6-manifold. The obstruction to integrability of almost complex structure (so-called Nijenhuis tensor) maps a 3-dimensional bundle to a 3-dimensional one. We say that Nijenhuis tensor is non-degenerate if it…

Differential Geometry · Mathematics 2008-04-13 Misha Verbitsky

The subject of this paper is six-dimensional nearly (para-)K\"ahler geometry with pseudo-Riemannian metrics. Firstly, we derive the analogue of the well-known exterior differential system characterising a nearly K\"ahler manifold and prove…

Differential Geometry · Mathematics 2009-12-18 Lars Schäfer , Fabian Schulte-Hengesbach

While small deformations of K\"ahler manifolds are K\"ahler too, we prove that the cohomological property to be $\mathcal{C}^\infty$-pure-and-full is not a stable condition under small deformations. This property, that has been recently…

Differential Geometry · Mathematics 2016-01-12 Daniele Angella , Adriano Tomassini

We show that the number of equivariant deformation classes of real structures in a given deformation class of compact hyperkahler manifolds is finite.

Algebraic Geometry · Mathematics 2008-03-21 Alex Degtyarev , Ilia Itenberg , Viatcheslav Kharlamov

For a compact complex manifold, we introduce holomorphic foliations associated with certain abelian subgroups of the automorphism group. Such foliations are generalizations of holomorphic principal torus bundles. If there exists a…

Complex Variables · Mathematics 2018-01-22 Hiroaki Ishida , Hisashi Kasuya

We investigate a class of locally conformal almost K\"ahler structures and prove that, under some conditions, this class is a subclass of almost K\"ahler structures. We show that a locally conformal almost K\"ahler manifold admits a…

General Mathematics · Mathematics 2021-04-02 Ntokozo Sibonelo Khuzwayo , Fortuné Massamba

In order to look for a well-behaved counterpart to Dolbeault cohomology in D-complex geometry, we study the de Rham cohomology of an almost D-complex manifold and its subgroups made up of the classes admitting invariant, respectively…

Differential Geometry · Mathematics 2012-09-04 Daniele Angella , Federico A. Rossi

On 5-dimensional almost contact B-metric manifolds, the form of any K\"ahler-type tensor (i.e. a tensor satisfying the properties of the curvature tensor of the Levi-Civita connection in the special class of the parallel structures on the…

Differential Geometry · Mathematics 2015-05-06 Mancho Manev , Miroslava Ivanova

We consider deformations of the scalar curvature of a partially integrable pseudohermitian manifold, in analogy with the work of Fischer and Marsden on Riemannian manifolds. In particular, we introduce and discuss $R$-singular spaces, give…

Differential Geometry · Mathematics 2024-04-11 Jeffrey S. Case , Pak Tung Ho

Let $\pi: \mathcal{X}^* \rightarrow B^*$ be an algebraic family of compact K\"ahler manifolds of complex dimension $n$ with negative first Chern class over a punctured disc $B^*\in \mathbb{C}$. Let $g_t$ be the unique K\"ahler-Einstein…

Differential Geometry · Mathematics 2017-06-07 Jian Song

Following an earlier paper on the differential-geometric structure of the moduli space of special Lagrangian submanifolds in a Calabi-Yau manifold, we follow an analogous approach for compact complex Lagrangian submanifolds of a…

Differential Geometry · Mathematics 2007-05-23 N J Hitchin

Let $(X,J,\omega,g)$ be a complete $n$-dimensional K\"ahler manifold. A Theorem by Gromov \cite{G} states that the if the K\"ahler form is $d$-bounded, then the space of harmonic $L_2$ forms of degree $k$ is trivial, unless $k=\frac{n}{2}$.…

Differential Geometry · Mathematics 2017-08-22 Richard Hind , Adriano Tomassini

The space $\mathcal{H}$ of "almost calibrated" $(1,1)$ forms on a compact K\"ahler manifold plays an important role in the study of the deformed Hermitian-Yang-Mills equation of mirror symmetry as emphasized by recent work of the second…

Differential Geometry · Mathematics 2021-09-15 Jianchun Chu , Tristan C. Collins , Man-Chun Lee

We discuss notions of almost complex, complex and K\"{a}hler structures in the realm of non-commutative geometry and investigate them for a class of finite dimensional spectral triples on the three-point space. We classify all the almost…

Quantum Algebra · Mathematics 2024-05-14 Suvrajit Bhattacharjee , Debashish Goswami

We establish a new criterion for a compatible almost complex structure on a symplectic four-manifold to be integrable and hence K\"ahler. Our main theorem shows that the existence of three linearly independent closed J-anti-invariant…

Differential Geometry · Mathematics 2015-09-04 Mehdi Lejmi , Markus Upmeier

We prove that for every compact K\"ahler manifold $X$ there exists an $L$-infinity morphism, lifting the usual cup product in cohomology, from the Kodaira-Spencer differential graded Lie algebra to the suspension of the space of linear…

Algebraic Geometry · Mathematics 2007-05-23 Marco Manetti

We study Laplace eigenvalues $\lambda_k$ on K\"ahler manifolds as functionals on the space of K\"ahler metrics with cohomologous K\"ahler forms. We introduce a natural notion of a $\lambda_k$-extremal K\"ahler metric and obtain necessary…

Differential Geometry · Mathematics 2015-02-03 Vestislav Apostolov , Dmitry Jakobson , Gerasim Kokarev