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Gerasimenko S.A., Rustanov A.R., Shchipkova N.N. ANALOGS IDENTITIES GRAY FOR TENSOR CONHARMONIC CURVATURE AC-MANIFOLDS OF CLASS C11 [№ 9 ' 2015] The main objective is to study the geometry of the curvature tensor conharmonic AC-class varieties C11. For this purpose, the following two problems are solved: 1) get contact analogues identities Gray conharmonic curvature tensor introduced in consideration of Ishi; 2) on the basis of these identities to isolate and study the subclasses of AC-class varieties C11. The paper identified three classes of almost contact metric manifolds class C11, named as GK1-, GK2- and GK3-manifolds. In Theoremš1 we obtain conditions on the curvature tensor components conharmonic on the space of the associated G-structure in which almost contact metric structure belongs to a class C11 selected classes. Theoremš2 is proved that the variety of AC-class C11 is GK3-manifold and the GK2-manifold. In Theoremš3 proved that AC-manifold of class C11, which is GK1-manifold is a manifold with Einstein's cosmological constant. In particular, in the case of completeness and continuity is compact and has a finite fundamental group. Finally, in Theoremš4 is proved that the variety of AC-class C11 dimension greater than 5 is GK1-manifold if and only if it is Ricci flat manifold.
Rustanov A.R., Gerasimenko S.A., Shchipkova N.N. THE GEOMETRY OF TENSOR CONHARMONIC CURVATURE AC-MANIFOLDS OF CLASSšC11 [№ 9 ' 2015] The main objective is to study the geometry of the curvature tensor conharmonic almost contact metric manifolds classšC11. To this end, following tasks: 1) calculate the basic essential components of curvature tensor conharmonic space of the associated G-structure; 2) explore conharmonic flat manifolds of classšC11; 3) get the identities satisfied by the curvature tensor conharmonic AC-class varietiesšC11; 4) select and explore some subclasses of AC-class varietiesšC11 of differential-geometric invariants of the second order. The paper addressed these problems. We prove the following theorem. Theoremš1: conharmonic flat AC-manifold of classšC11 is Ricci-flat manifold. Theoremš2: conharmonic flat AC-manifold of classšC11 is a manifold of Einstein. Theoremš3: conharmonic flat AC-manifold of classšC11 is a flat manifold. Theoremš4: AC-manifold of classšC11 is a manifold of classšK1 if and only if the AC-manifold of classšC11 is Ricci-flat manifold. Theoremš5: AC-manifold of classšC11 is a manifold of classšK2 if and only if the AC-manifold of classšC11 is Ricci-flat manifold. Theoremš6: AC-manifold of classšC11 is a manifold of classšK3 if and only if the AC-manifold of classšC11 is a flat manifold. Theoremš7: AC-manifold of classšC11, a manifold of classšK4 is a manifold of class Einstein's cosmological constant. In particular, in the case of completeness and continuity is compact and has a finite fundamental group. Theoremš8. AC-manifold of classšC11 dimension greater thanš5 is K4-manifold if and only if it is Ricci flat manifold.
Rustanov A.R., Shchipkova N.N. GEOMETRY OF CLASS C11AC-MANIFOLDS CONCIRCULAR CURVATURE TENSOR [№ 9 ' 2014] This paper describes the geometry of concircular curvature tensor in AC-manifolds of class C11. We have calculated its components for the space of the associated G-structure, derivated identities satisfied by the concircular curvature tensor. On the basis of these identities allocated some subclasses of AC-manifolds of class C11 and derivated local characterization of selected classes.
Rustanov A.R., Shchipkova N.N. DIFFERENTIAL GEOMETRY OF CONTACT METRIC MANIFOLDS OF Nó11 CLASS [№ 1 ' 2013] This paper considers a new class of contact metric manifolds, which generalizes the class of áó-manifolds of the ó11 class by the classification of Chinya and Gonzalez. The complete group of structural equations for NC11-manifolds derived, and components of Riemann-Christoffel tensor, Ricci tensor and the scalar curvature are computed basing on these equations. Properties of NC11-manifolds are derived. Some identities of the Riemann curvature tensor are derived, too.
Rustanov A.R., Shchipkova N.N. CURVATURE IDENTITIES OF CLASS C11 MANIFOLD [№ 6 ' 2011] The article deals with the AU-manifold of class C11, which generalize the class of skew-symplectic manifolds. The identities of the curvature of this class manifold are obtained. As a consequence, the expression of the tensor F-sectional curvature tensor by the Riemannš— Christoffel tensor was got.
Rustanov A.R., Shchipkova N.N. THE DIFFERENTIAL GEOMETRY OF THE ALMOST CONTACT METRIC VARIETIES OF THE CLASS S11. [№ 9 ' 2010] The work examined the new class of almost contact metric varieties, the generalizing class of cosimplect varieties. The authors got the complete classification of the AS-varieties of the class S11 of a constant F-holomorphic sectional curvature.
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Editor-in-chief |
Sergey Aleksandrovich MIROSHNIKOV |
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