Results 1 to 10 of about 5,989 (167)
On contact CR-submanifolds of sasakian manifolds [PDF]
International Journal of Mathematics and Mathematical Sciences, 1983 Recently, K.Yano and M.Kon [5] have introduced the notion of a contact CR-submanifold of a Sasakian manifold which is closely similar to the one of a CR-submanifold of a Kaehlerian manifold defined by A. Bejancu [1].
Koji Matsumoto
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Differential Geometry and its Applications, 2022 In this paper we show that two Kähler manifolds which do not share a Kähler submanifold, do not share either a Levi degenerate CR-submanifold with constant dimension Levi kernel. In particular, they do not share a CR-product. Further, we obtain that a Levi degenerate CR-submanifold of $\mathbb C^n$ cannot be isometrically immersed into a flag manifold.
Marini, Stefano, Zedda, Michela
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ON HOMOGENEOUS CR MANIFOLDS AND THEIR CR ALGEBRAS [PDF]
International Journal of Geometric Methods in Modern Physics, 2006 In this paper we show some results on homogeneous CR manifolds, proved by introducing their associated CR algebras. In particular, we give different notions of nondegeneracy (generalizing the usual notion for the Levi form) which correspond to geometrical properties for the corresponding manifolds.
A. Altomani, MEDORI, Costantino
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CR Manifolds Admitting a CR Contraction [PDF]
Journal of Geometric Analysis, 2010 We classify the germs of $\mathcal{C}^\infty$ CR manifolds that admit a smooth CR contraction. We show that such a CR manifold is embedded into $\CC^n$ as a real hypersurface defined by a polynomial defining function consisting of monomials whose degrees are completely determined by the extended resonances of the contraction.
Kim, KT, Yoccoz, JC
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CR Embedded Submanifolds of CR Manifolds [PDF]
Memoirs of the American Mathematical Society, 2019 We develop a complete local theory for CR embedded submanifolds of CR manifolds in a way which parallels the Ricci calculus for Riemannian submanifold theory. We define a normal tractor bundle in the ambient standard tractor bundle along the submanifold and show that the orthogonal complement of this bundle is not canonically isomorphic to the standard
Curry, Sean N., Gover, A. Rod
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Annali di Matematica Pura ed Applicata (1923 -), 2022 AbstractWe improve results of Baouendi, Rothschild and Treves and of Hill and Nacinovich by finding a much weaker sufficient condition for a CR manifold of type (n, k) to admit a local CR embedding into a CR manifold of type $$(n+\ell ,k-\ell )$$ ( n + ℓ
Cowling, MG +3 more
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Ultradifferentiable CR Manifolds [PDF]
The Journal of Geometric Analysis, 2019 In this article the notion of ultradifferentiable CR manifold is introduced and an ultradifferentiable regularity result for finitely nondegenerate CR mappings is proven. Here ultradifferentiable means with respect to Denjoy-Carleman classes defined by weight sequences. Furthermore the regularity of infinitesimal CR automorphisms on ultradifferentiable
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Partially integrable almost CR structures
Complex Manifolds, 2021 Let (M, D) be a compact contact manifold with dimRM = 2n ≥ 5. This means that: M is a C∞ differential manifold with dimRM = 2n ≥ 5. And D is a subbundle of the tangent bundle TM which satisfying; there is a real one form θ such that D = {X : X ∈ TM, θ(X)
Akahori Takao
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Some results on the geometry of warped product CR-submanifolds in quasi-Sasakian manifold
Cubo, 2022 The present paper deals with a study of warped product submanifolds of quasi-Sasakian manifolds and warped product CR-submanifolds of quasi-Sasakian manifolds.
Shamsur Rahman
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On the Curvature Groups of a CR Manifold [PDF]
Mediterranean Journal of Mathematics, 2006 We show that any contact form whose Fefferman metric admits a nonzero parallel vector field is pseudo-Einstein of constant pseudohermitian scalar curvature. As an application we compute the curvature groups of the total space of the canonical circle bundle over a CR manifold.
BARLETTA, Elisabetta, DRAGOMIR, Sorin
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