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Fiberings on almost $r$-contact manifolds
Publicationes Mathematicae Debrecen, 1993Let \(M\) be a \((2m+r)\)-dimensional Riemannian manifold endowed with an almost \(r\)-contact structure defined by the Reeb vector fields \(\xi_ s\) \((s,t\in \{2m+1,\dots,2m+r\})\) and let \(\eta^ s\) be the associated Reeb covectors, i.e. \(\eta^ t(\xi_ s)= \delta_{t^ s}\).
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A generalization of normal almost contact manifolds
Summary: In this article, a new definition, called \(\varphi \)-normal, is introduced, which is a generalization of normal condition on almost contact manifolds. Then some examples of \(\varphi \)-normal almost contact manifolds that are not normal are presented, and a sufficient and necessary condition for equivalence of these two definitions in 3 ...Malek, Fereshteh +1 more
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On Conformally Flat Almost Contact Metric Manifolds
Mediterranean Journal of Mathematics, 2015zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Blair, David E., Yıldırım, Handan
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Distributions on almost contact manifolds
Acta Mathematica Scientia, 2017Abstract It is known that any hypersurface in an almost complex space admits an almost contact manifold [11, 14]. In this article we show that a hyperplane in an almost contact manifold has an almost complex structure. Along with this result, we explain how to determine when an almost contact structure induces a contact structure, followed by ...
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On statistical almost contact manifolds
Journal of Geometry and PhysicszbMATH Open Web Interface contents unavailable due to conflicting licenses.
S. Mehrshad, B. Najafi
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ALMOST CONTACT 3-MANIFOLDS AND RICCI SOLITONS
International Journal of Geometric Methods in Modern Physics, 2012A Kenmotsu 3-manifold M admitting a Ricci soliton (g, w) with a transversal potential vector field w (orthogonal to the Reeb vector field) is of constant sectional curvature -1. A cosymplectic 3-manifold admitting a Ricci soliton with the Reeb potential vector field or a transversal vector field is of constant sectional curvature 0.
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A classification of almost contact metric manifolds
Annali di Matematica Pura ed Applicata, 1990An almost contact manifold is a \(C^{\infty}\) manifold \(M^{2n+1}\) whose structural group can be reduced to U(n)\(\times 1\); equivalently M admits a tensor field \(\phi\) of type (1,1), a vector field \(\xi\) and a 1- form \(\eta\) such that \(\phi^ 2=-I+\eta \otimes \sigma\) and \(\eta (\xi)=1\).
Chinea, D., Gonzalez, C.
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Curvature of indefinite almost contact manifolds
Journal of Geometry, 1997The authors investigate the curvature properties of indefinite almost contact manifolds \((M,\varphi,\xi,\) \(\eta,g).\) Formally, \((\varphi,\xi,\eta,g)\) is an almost contact metric structure on the differentiable manifold \(M\) [cf., e.g., \textit{D. E. Blair} [Contact manifolds in Riemannian geometry. Lect. Notes Math.
Bonome, Agustín +3 more
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Almost contact hypersurfaces of certain almost complex manifolds
1969This item was digitized as part of a project to share McGill's intellectual legacy with the public. If you are the copyright holder or a relative of the copyright holder who is deceased, you may request withdrawal by emailing escholarship.library@mcgill.ca.
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