Results 21 to 30 of about 220,418 (211)
A note on η-quasi-umbilical hypersurfaces in almost Hermitian manifolds
Дифференциальная геометрия многообразий фигур, 2023 In the present note, we consider the introduced by Lidia Vasil’evna Stepanova notion of an -quasi-umbilical hypersurface in an almost Hermitian manifold.
M. B. Banaru
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On nearly Kählerian manifolds and quasi-Sasakian hypersurfaces axiom
Дифференциальная геометрия многообразий фигур, 2021 It is known that an almost contact metric structure is induced on an arbitrary hypersurface of an almost Hermitian manifold. The case when the almost Hermitian manifold is nearly Kählerian and the almost contact metric structure on its hypersurface is ...
G.A. Banaru
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Almost contact structures on the set of rational curves in a 4-dimensional twistor space [PDF]
Kodai Mathematical Journal, 2022 In this paper, we provide a correspondence between certain 5-dimensional complex spacetimes and 4-dimensional twistor spaces. The spacetimes are almost contact manifolds whose curvature tensor satisfies certain conditions. By using the correspondence, we
Michifumi Teruya
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Contact-Complex Riemannian Submersions
Mathematics, 2021 A submersion from an almost contact Riemannian manifold to an almost Hermitian manifold, acting on the horizontal distribution by preserving both the metric and the structure, is, roughly speaking a contact-complex Riemannian submersion. This paper deals
Cornelia-Livia Bejan +2 more
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Lifting semi-invariant submanifolds to distribution of almost contact metric manifolds
Дифференциальная геометрия многообразий фигур, 2020 Let M be an almost contact metric manifold of dimension n = 2m + 1. The distribution D of the manifold M admits a natural structure of a smooth manifold of dimension n = 4m + 1.
A. Bukusheva
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On canonical-type connections on almost contact complex Riemannian manifolds [PDF]
, 2014 We consider a pair of smooth manifolds, which are the counterparts in the even-dimensional and odd-dimensional cases. They are separately an almost complex manifold with Norden metric and an almost contact manifolds with B-metric, respectively.
Manev, Mancho
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Generalized almost para-contact manifolds [PDF]
International Journal of Geometric Methods in Modern Physics, 2017 In this paper, we study generalized almost para-contact manifolds and obtain normality conditions in terms of classical tensor fields. We show that such manifolds naturally carry certain Lie bialgebroid/quasi-Lie algebroid structures on them and we relate these new generalized manifolds with classical almost para-contact manifolds.
Bayram Ṣahin, Fulya Ṣahin
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Almost contact metric manifolds with certain condition
Annals of Global Analysis and Geometry, 2023 The object of this article is to study a new class of almost contact metric structures which are integrable but non normal. Secondly, we explain a method of construction for normal manifold starting from a non-normal but integrable manifold. Illustrative
Benaoumeur Bayour +2 more
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Existence and Nonexistence of Warped Product Submanifolds of Almost Contact Manifolds [PDF]
International Electronic Journal of Geometry, 2022 This paper has two goals; the first is to generalize results for the existence and nonexistence of warped product submanifolds of almost contact manifolds, accordingly a self-contained reference of such submanifolds is offered to save efforts of ...
Abdulqader Mustafa +3 more
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Дифференциальная геометрия многообразий фигур, 2019 Almost contact metric (аст-)structures induced on oriented hypersurfaces of a Kählerian manifold are considered in the case when these аст-structures are of cosymplectic type, i. e. the contact form of these structures is closed. As it is known, the
G. Banaru
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