Results 11 to 20 of about 241 (30)
A class of 3-dimensional almost Kenmotsu manifolds with harmonic curvature tensors
Open Mathematics, 2016 Let M3 be a three-dimensional almost Kenmotsu manifold satisfying ▽ξh = 0. In this paper, we prove that the curvature tensor of M3 is harmonic if and only if M3 is locally isometric to either the hyperbolic space ℍ3(-1) or the Riemannian product ℍ2(−4) ×
Wang Yaning
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A dimensional restriction for a class of contact manifolds
Demonstratio Mathematica, 2017 In this work we consider a class of contact manifolds (M, η) with an associated almost contact metric Structure (ϕ, ξ, η, g). This class contains, for example, nearly cosymplectic manifolds and the manifolds in the class C9 ⊕ C10 defined by Chinea and ...
Loiudice Eugenia
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Ricci solitons in three-dimensional paracontact geometry [PDF]
, 2014 We completely describe paracontact metric three-manifolds whose Reeb vector field satisfies the Ricci soliton equation. While contact Riemannian (or Lorentz\-ian) Ricci solitons are necessarily trivial, that is, $K$-contact and Einstein, the paracontact ...
Calvaruso, Giovanni, Perrone, Antonella
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The twistor space of a quaternionic contact manifold [PDF]
, 2010 We show that the CR structure on the twistor space of a quaternionic contact structure described by Biquard is normal if and only if the Ricci curvature of the Biquard connection commutes with the endomorphisms in the quaternionic structure of the ...
Davidov, Johann +2 more
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*-Ricci soliton on (κ, μ)′-almost Kenmotsu manifolds
Open Mathematics, 2019 Let (M, g) be a non-Kenmotsu (κ, μ)′-almost Kenmotsu manifold of dimension 2n + 1. In this paper, we prove that if the metric g of M is a *-Ricci soliton, then either M is locally isometric to the product ℍn+1(−4)×ℝn or the potential vector field is ...
Dai Xinxin, Zhao Yan, Chand De Uday
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Open Mathematics, 2015 In this paper three dimensional real hypersurfaces in non-flat complex space forms whose k-th Cho operator with respect to the structure vector field ξ commutes with the structure Jacobi operator are classified.
Panagiotidou Konstantina +1 more
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A neutral relation between metallic structure and almost quadratic {\phi}-structure
, 2018 In this paper, metallic structure and almost quadratic metric phi-structure are studied. Based on metallic (polynomial) Riemannian manifold, Kenmotsu quadratic metric manifold, cosymplectic quadratic metric manifold are defined and gave some examples ...
Erken, İrem Küpeli +3 more
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Contact boundaries of hypersurface singularities and of complex polynomials
, 2003 We survey some recent results concerning the behaviour of the contact structure defined on the boundary of a complex isolated hypersurface singularity or on the boundary at infinity of a complex polynomial.Comment: 8 pages; to be published in the ...
Caubel, C., Tibar, M.
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Matrix Lie groups as 3-dimensional almost contact B-metric manifolds [PDF]
, 2015 The object of investigation are Lie groups considered as almost contact B-metric manifolds of the lowest dimension three. It is established a correspondence of all basic-class-manifolds of the Ganchev-Mihova-Gribachev classification of the studied ...
Manev, Hristo
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On the structure tensors of almost contact B-metric manifolds
, 2014 The space of the structure (0,3)-tensors of the covariant derivatives of the structure endomorphism and the metric on almost contact B-metric manifolds is considered.
Manev, Hristo
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