Results 31 to 40 of about 369 (176)
Estimates for a function on almost Hermitian manifolds
Complex Manifolds, 2021 We study some estimates for a real-valued smooth function φ on almost Hermitian manifolds. In the present paper, we show that ∂∂∂̄ φ and ∂̄∂∂̄ φ can be estimated by the gradient of the function φ.
Kawamura Masaya
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The differential geometry of almost Hermitian almost contact metric submersions
International Journal of Mathematics and Mathematical Sciences, 2004 Three types of Riemannian submersions whose total space is an almost Hermitian almost contact metric manifold are studied. The study is focused on fundamental properties and the transference of structures.
T. Tshikuna-Matamba
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GENERELIZED CONHARMONIC CURVATURE TENSOR OF NEARLY KAHLER MANIFOLD
Tikrit Journal of Pure Science, 2018 In this paper we study the relationship between tensor algebraic curvature tensor, and General conharmonic curvature tensor of Nearly Kahler manifold, i. e. it has a classical symmetry properties of the Riemann carvatur tensor.
Ali A. Shihab, Dhabiaʼa M. Ali
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Advanced Intelligent Systems, EarlyView.The phase discontinuity problem—where the cyclic nature of phase angles causes catastrophic errors near the ±π boundary—is a fundamental obstacle in learning‐based reconfigurable intelligent surface (RIS) optimization. A phase‐aware hybrid CNN–LSTM framework resolves this by decomposing phase predictions into sine–cosine components, mapping circular ...
Seda Savaşçı Şen +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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Almost Complex and Hypercomplex Norden Structures Induced by Natural Riemann Extensions
Mathematics, 2022 The Riemann extension, introduced by E. K. Patterson and A. G. Walker, is a semi-Riemannian metric with a neutral signature on the cotangent bundle T∗M of a smooth manifold M, induced by a symmetric linear connection ∇ on M.
Cornelia-Livia Bejan, Galia Nakova
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Quantization of Polaritons Confined in Dielectric Structures
Laser &Photonics Reviews, EarlyView.This study addresses the limitations of the Hopfield model of strong light‐matter coupling in the case of structured dieletrics. A method to derive quantum models in the polariton basis using Bogoliubov transformation and third quantization is introduced, demonstrating how to boost interaction strength and engineer nonlocal interactions for strongly ...
Amir Rahmani +4 more
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Neutral Slant Submanifolds of a Para-Kähler Manifold
Abstract and Applied Analysis, 2013 We define and study both neutral slant and semineutral slant submanifolds of an almost para-Hermitian manifold and, in particular, of a para-Kähler manifold. We give characterization theorems for neutral slant and semi-neutral slant submanifolds. We also
Yılmaz Gündüzalp
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Yano F structures and extended supersymmetry
Journal of High Energy Physics, 2022 It is shown how extended supersymmetry realised directly on the (2, 2) semichiral superfields of a symplectic sigma model gives rise to a geometry on the doubled tangent bundle consisting of two Yano F structures on an almost para-hermitian manifold ...
Ulf Lindström
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Non-Existence of Real Hypersurfaces with Parallel Structure Jacobi Operator in S6(1)
Mathematics, 2022 It is well known that the sphere S6(1) admits an almost complex structure J which is nearly Kähler. If M is a hypersurface of an almost Hermitian manifold with a unit normal vector field N, the tangent vector field ξ=−JN is said to be characteristic or ...
Miroslava Antić, Djordje Kocić
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