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Related papers: CR-submanifolds. A class of examples

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In this paper we introduce paraquaternionic CR-submanifolds of almost paraquaternionic hermitian manifolds and state some basic results on their differential geometry. We also study a class of semi-Riemannian submersions from…

Differential Geometry · Mathematics 2010-07-13 Stere Ianus , Stefano Marchiafava , Gabriel Eduard Vilcu

In this paper, we deal with a strongly pseudoconvex almost CR manifold with a CR contraction. We will prove that the stable manifold of the CR contaction is CR equivalent to the Heisenberg group model.

Complex Variables · Mathematics 2022-08-04 Jae-Cheon Joo , Kang-Hyurk Lee

It is constructed a Formal Normal Form for a Special Class of Real-Smooth Submanfolds in $\mathbb{C}^{2N}$.

Complex Variables · Mathematics 2023-12-27 Valentin Burcea

In this paper we describe the algebra of differential invariants for GL(n,C)-structures. This leads to classification of almost complex structures of general positions. The invariants are applied to the existence problem of…

Differential Geometry · Mathematics 2007-12-21 Boris Kruglikov

In this companion paper to our article {\em Accidental CR structures} (arxiv.org, January 2023), thought of as an appendix not submitted for publication, we provide complete explicit lists of infinitesimal CR automorphisms for the concerned…

Complex Variables · Mathematics 2023-02-14 C. Denson Hill , Joël Merker , Zhaohu Nie , Paweł Nurowski

The class of special generic maps contains Morse functions with exactly two singular points, characterizing spheres topologically which are not $4$-dimensional and the $4$-dimensional unit sphere. This class is for higher dimensional…

Algebraic Topology · Mathematics 2022-09-20 Naoki Kitazawa

We classify pseudo parallel proper CR-submanifolds in a non-flat complex space form with CR-dimension greater than one. With this result, the non-existence of recurrent as well as semi parallel proper CR-submanifolds in a non-flat complex…

Differential Geometry · Mathematics 2014-02-24 Avik De , Tee-How Loo

In this paper we introduce the notion of bi-slant submanifolds of a para Hermitian manifold. They naturally englobe CR, semi-slant and hemi-slant submanifolds. We study their first properties and present a whole gallery of examples.

General Mathematics · Mathematics 2019-01-10 P. Alegre , A. Carriazo

Homotopy comomentum maps are a higher generalization of the notion of moment map introduced to extend the concept of Hamiltonian actions to the framework of multisymplectic geometry. Loosely speaking, higher means passing from considering…

Symplectic Geometry · Mathematics 2025-11-10 Antonio Michele Miti

The properties of multimomentum maps on null hypersurfaces, and their relation with the constraint analysis of General Relativity, are described. Unlike the case of spacelike hypersurfaces, some constraints which are second class in the…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Cosimo Stornaiolo , Giampiero Esposito

CR-hypersurfaces of conformal Kenmotsu space form satisfying certain shape operator conditions

Differential Geometry · Mathematics 2014-12-10 R. Abdi , E. Abedi

A complex filling of a CR manifold is said to be equivariant with respect to a CR action if the action extends to a smooth action by biholomorphisms on the whole filling. Under a noncompactness condition for the action, we describe all…

Differential Geometry · Mathematics 2009-01-05 Benoit Kloeckner

We show that the vanishing of the higher dimensional homology groups of a manifold ensures that every almost CR structure of codimension $k$ may be homotoped to a CR structure. This result is proved by adapting a method due to Haefliger…

Complex Variables · Mathematics 2014-05-09 Howard Jacobowitz , Peter Landweber

It is constructed a normal form for a class of real-smooth surfaces M\subset\mathbb{C}^{2} defined near a degenerate CR singularity.

Complex Variables · Mathematics 2026-05-26 Valentin Burcea

Given a Lie group acting on a manifold $M$ preserving a closed $n+1$-form $\omega$, the notion of homotopy moment map for this action was introduced in Callies-Fregier-Rogers-Zambon [6], in terms of $L_{\infty}$-algebra morphisms. In this…

Differential Geometry · Mathematics 2016-06-30 Yael Fregier , Camille Laurent-Gengoux , Marco Zambon

In this paper we study holomorphically homogeneous model submanifolds CR-type (1, 3) complex space $\mathbb C^4$. One finds moduli space of five-dimensional model surfaces Bloom-Graham type ((2, 1), (3, 1), (4, 1)). It is shown that there…

Complex Variables · Mathematics 2024-05-15 Ilya Zavolokin

An explicit classification of simply connected compact homogeneous CR manifolds G/L of codimension one, with non-degenerate Levi form, is given. There are three classes of such manifolds: a) the standard CR homogeneous manifolds which are…

Differential Geometry · Mathematics 2007-05-23 Dmitry V. Alekseevsky , Andrea F. Spiro

We improve previous results by exhibiting a construction that contains all known examples. A suficient condition for the existence of robustly transitive maps displaying singularities on a certain large class of compact manifolds is given.

Dynamical Systems · Mathematics 2021-05-10 Juan Carlos Morelli

In this paper, we construct uncountably many examples of multiparameter CCR flows, which are not pullbacks of $1$-parameter CCR flows, with index one. Moreover, the constructed CCR flows are type I in the sense that the associated product…

Operator Algebras · Mathematics 2021-08-12 Piyasa Sarkar , S. Sundar

In this paper, we investigate the problem of prescribing Webster scalar curvatures on compact pseudo-Hermitian manifolds. In terms of the method of upper and lower solutions and the perturbation theory of self-adjoint operators, we can…

Differential Geometry · Mathematics 2021-04-30 Yuxin Dong , Yibin Ren , Weike Yu