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Related papers: Sasakian structures on CR-manifolds

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We construct a Kahler structure (which we call a generalised Kahler cone) on an open subset of the cone of a strongly pseudo-convex CR manifold endowed with a 1-parameter family of compatible Sasaki structures. We determine those…

Differential Geometry · Mathematics 2014-01-14 Liana David

Let $(X,T^{1,0}X)$ be a compact strictly pseudoconvex CR manifold which is CR embeddable into the complex Euclidean space. We show that $T^{1,0}X$ can be approximated in $\mathscr{C}^\infty$-topology by a sequence of strictly pseudoconvex…

Complex Variables · Mathematics 2025-10-14 Hendrik Herrmann , Chin-Yu Hsiao , Bernhard Lamel

The main result of this paper is that the identity component of the automorphism group of a compact, connected, strictly pseudoconvex CR manifold is compact unless the manifold is CR equivalent to the standard sphere. In dimensions greater…

Complex Variables · Mathematics 2009-09-25 John M. Lee

In this note we give an explicit construction of Sasaki-Einstein metrics on a class of simply connected 7-manifolds with the rational cohomology of the 2-fold connected sum of $S^2\times S^5$. The homotopy types are distinguished by torsion…

Differential Geometry · Mathematics 2019-06-18 Charles P. Boyer , Christina Tønnesen-Friedman

We construct some families of complex structures on compact manifolds by means of normal almost contact structures (nacs) so that each complex manifold in the family has a non-singular holomorphic flow. These families include as particular…

Differential Geometry · Mathematics 2007-05-23 Monica Manjarin

For a strongly pseudo-convex complex Finsler manifold M, a bundle U of adapted unitary frames is canonically defined. A non-linear Hermitian connection on U, invariant under local biholomorphic isometries, is given and it proved to be…

Differential Geometry · Mathematics 2007-05-23 Andrea Spiro

Motivated by the geometry of Levi degenerate CR hypersurfaces, we define a pre-K\"ahler structure on a complex manifold as a pre-symplectic structure compatible with the almost complex structure, i.e. a closed (1,1)-form. Extending Freeman…

Differential Geometry · Mathematics 2025-05-16 Omid Makhmali , David Sykes

For the Riemannian manifold $M^{n}$ two special connections on the sum of the tangent bundle $TM^{n}$ and the trivial one-dimensional bundle are constructed. These connections are flat if and only if the space $M^{n}$ has a constant…

Differential Geometry · Mathematics 2009-11-07 Alexey V. Shchepetilov

The theory of $G$-structures provides us with a unified framework for a large class of geometric structures, including symplectic, complex and Riemannian structures, as well as foliations and many others. Surprisingly, contact geometry -…

Differential Geometry · Mathematics 2020-03-10 Alfonso G. Tortorella , Luca Vitagliano , Ori Yudilevich

We classify locally homogeneous quasi-Sasakian manifolds in dimension five that admit a parallel spinor $\psi$ of algebraic type $F \cdot \psi = 0$ with respect to the unique connection $\nabla$ preserving the quasi-Sasakian structure and…

Differential Geometry · Mathematics 2007-05-23 Thomas Friedrich , Stefan Ivanov

We prove that any contact metric $(\kappa,\mu)$-space $(M,\xi,\phi,\eta,g)$ admits a canonical paracontact metric structure which is compatible with the contact form $\eta$. We study such canonical paracontact structure, proving that it…

Differential Geometry · Mathematics 2013-06-18 Beniamino Cappelletti Montano , Luigia di Terlizzi

We prove that an integrable system over a symplectic manifold, whose symplectic form is covariantly constant w.r.t. the Gauss-Manin connection, carries a natural hyper-symplectic structure. Moreover, a special Kaehler structure is induced…

Differential Geometry · Mathematics 2009-11-10 C. Bartocci , I. Mencattini

Let $G/H$ be a contractible homogeneous Sasaki manifold. A compact locally homogeneous aspherical Sasaki manifold $\Gamma\big\backslash G/H$ is by definition a quotient of $G/H$ by a discrete uniform subgroup $\Gamma\leq G$. We show that a…

Differential Geometry · Mathematics 2020-04-21 Oliver Baues , Yoshinobu Kamishima

Under a pulled-back approach given in [1] and firstly presented in [2], we introduce, in this paper, the concepts of almost contact and normal almost contact Finsler structures on the pulled-back bundle. Properties of structures partly…

Differential Geometry · Mathematics 2016-06-22 Fortuné Massamba , Salomon Joseph Mbatakou

In this paper, we compute contact homology of some quasi-regular contact structures, which admit Hamiltonian actions of Reeb type of Lie groups. We will discuss the toric contact case, (where the torus is of Reeb type), and the case of…

Symplectic Geometry · Mathematics 2009-11-02 Justin Pati

Let M be a six dimensional manifold, endowed with a cohomogeneity one action of G= SU_2 x SU_2, and M_reg its subset of regular points. We show that M_reg admits a smooth, 2-parameter family of G-invariant, non-isometric strict nearly…

Differential Geometry · Mathematics 2010-11-23 Andrea Spiro , Fabio Podesta'

We give a precise characterization when a compact homogeneous CR-solvmanifold is CR-embeddable in a Kahler manifold. Equivalently this gives a non-Kahler criterion for complex manifolds containing CR-solvmanifolds not satisfying these…

Complex Variables · Mathematics 2009-10-01 Bruce Gilligan , Karl Oeljeklaus

The purpose of this article is to study co-dimension $2$ iso-contact embeddings of closed contact manifolds. We first show that a closed contact manifold $(M^{2n-1}, \xi_M)$ iso-contact embeds in a contact manifold $(N^{2n+1}, \xi_N),$…

Symplectic Geometry · Mathematics 2019-09-11 Dishant M. Pancholi , Suhas Pandit

We obtain some general results on Sasakian Lie algebras and prove as a consequence that a (2n + 1)-dimensional nilpotent Lie group admitting left-invariant Sasakian structures is isomorphic to the real Heisenberg group $H_{2n + 1}$.…

Differential Geometry · Mathematics 2009-03-12 Adrian Andrada , Anna Fino , Luigi Vezzoni

We introduce the notion of a special complex manifold: a complex manifold (M,J) with a flat torsionfree connection \nabla such that (\nabla J) is symmetric. A special symplectic manifold is then defined as a special complex manifold…

Differential Geometry · Mathematics 2015-06-26 D. V. Alekseevsky , V. Cortés , C. Devchand