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Einstein-Hermitian and anti-Hermitian 4-manifolds

Włodzimierz Jelonek (2003)

Annales Polonici Mathematici

We study 4-dimensional Einstein-Hermitian non-Kähler manifolds admitting a certain anti-Hermitian structure. We also describe Einstein 4-manifolds which are of cohomogeneity 1 with respect to an at least 4-dimensional group of isometries.

Equitorsion holomorphically projective mappings of generalized Kählerian space of the first kind

Mića S. Stanković, Milan Lj. Zlatanović, Ljubica S. Velimirović (2010)

Czechoslovak Mathematical Journal

In this paper we define generalized Kählerian spaces of the first kind ( G K 1 N ) given by (2.1)–(2.3). For them we consider hollomorphically projective mappings with invariant complex structure. Also, we consider equitorsion geodesic mapping between these two spaces ( G K 1 N and G K ¯ 1 N ) and for them we find invariant geometric objects.

Geodesic mapping onto Kählerian spaces of the first kind

Milan Zlatanović, Irena Hinterleitner, Marija Najdanović (2014)

Czechoslovak Mathematical Journal

In the present paper a generalized Kählerian space 𝔾 𝕂 1 N of the first kind is considered as a generalized Riemannian space 𝔾ℝ N with almost complex structure F i h that is covariantly constant with respect to the first kind of covariant derivative. Using a non-symmetric metric tensor we find necessary and sufficient conditions for geodesic mappings f : 𝔾ℝ N 𝔾 𝕂 ¯ 1 N with respect to the four kinds of covariant derivatives. These conditions have the form of a closed system of partial differential equations in covariant derivatives...

Hermitian Manifolds of Pointwise Constant Antiholomorphic Sectional Curvatures

Ganchev, Georgi, Kassabov, Ognian (2007)

Serdica Mathematical Journal

2000 Mathematics Subject Classification: Primary 53B35, Secondary 53C50.In dimension greater than four, we prove that if a Hermitian non-Kaehler manifold is of pointwise constant antiholomorphic sectional curvatures, then it is of constant sectional curvatures.

Higher order contact of real curves in a real hyperquadric. II

Yuli Villarroel (1998)

Archivum Mathematicum

Let Φ be an Hermitian quadratic form, of maximal rank and index ( n , 1 ) , defined over a complex ( n + 1 ) vector space V . Consider the real hyperquadric defined in the complex projective space P n V by Q = { [ ς ] P n V , Φ ( ς ) = 0 } . Let G be the subgroup of the special linear group which leaves Q invariant and D the ( 2 n ) - distribution defined by the Cauchy Riemann structure induced over Q . We study the real regular curves of constant type in Q , tangent to D , finding a complete system of analytic invariants for two curves to be locally equivalent...

Holomorphically projective mappings of compact semisymmetric manifolds

Raad J. K. al Lami (2010)

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

In this paper we consider holomorphically projective mappings from the compact semisymmetric spaces A n onto (pseudo-) Kählerian spaces K ¯ n . We proved that in this case space A n is holomorphically projective flat and K ¯ n is space with constant holomorphic curvature. These results are the generalization of results by T. Sakaguchi, J. Mikeš, V. V. Domashev, N. S. Sinyukov, E. N. Sinyukova, M. Škodová, which were done for holomorphically projective mappings of symmetric, recurrent and semisymmetric Kählerian...

Invariant connections and invariant holomorphic bundles on homogeneous manifolds

Indranil Biswas, Andrei Teleman (2014)

Open Mathematics

Let X be a differentiable manifold endowed with a transitive action α: A×X→X of a Lie group A. Let K be a Lie group. Under suitable technical assumptions, we give explicit classification theorems, in terms of explicit finite dimensional quotients, of three classes of objects: equivalence classes of α-invariant K-connections on X α-invariant gauge classes of K-connections on X, andα-invariant isomorphism classes of pairs (Q,P) consisting of a holomorphic Kℂ-bundle Q → X and a K-reduction P of Q (when...

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