Results 21 to 30 of about 71,420 (241)
Ricci curvature and volume growth [PDF]
Pacific Journal of Mathematics, 1991 The well known Bishop-Gromov inequality for the volume growth of balls in a Riemannian manifold \(M\) has an analogue for tubes around a compact totally geodesic submanifold \(L\subset M\), but instead of a lower Ricci curvature bound one has to assume a lower bound \(\kappa\) for the radial sectional curvatures of \(M\) with respect to \(L\).
Strake, M., Walschap, G.
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Curvature Inheritance Symmetry in Ricci Flat Spacetimes
Universe, 2022 In this article, we study curvature inheritance symmetry in Ricci flat spacetimes. We show that, if Ricci flat spacetimes are not of Petrov type N, and admit curvature inheritance symmetries, then the only existing symmetries are conformal motions.
Mohammad Salman +2 more
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Ricci curvature and orientability [PDF]
Calculus of Variations and Partial Differential Equations, 2017 49 pages.
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Ricci curvature and minimal submanifolds [PDF]
Pacific Journal of Mathematics, 2001 This paper studies isometric minimal immersions \(f\) of a complete orientable Riemannian \(n\)-manifold \(M\) into the round sphere \(S^{n+k}\). Theorem A: If \(k=1\), then the supremum of Ric\((M)\) is \(\geq n-2\). Moreover, if the supremum equals \(n-2\), then if \(n\) is odd, the universal cover of \(M\) is homomorphic to \(S^n\), and if \(n\) is ...
Hasanis, T., Vlachos, T.
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On the Geometry of Three-dimensional Pseudo-Riemannian Homogeneous Spaces. I [PDF]
Известия Саратовского университета. Новая серия: Математика. Механика. Информатика, 2020 The problem of establishing links between the curvature and the topological structure of a manifold is one of the important problems of geometry. In general, the purpose of the research of manifolds of various types is rather complicated.
Natal’ya Pavlovna Mozhey
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The Ricci curvature in noncommutative geometry [PDF]
Journal of Noncommutative Geometry, 2019 Motivated by the local formulae for asymptotic expansion of heat kernels in spectral geometry, we propose a definition of Ricci curvature in noncommutative settings. The Ricci operator of an oriented closed Riemannian manifold can be realized as a spectral functional, namely the functional defined by the zeta function of the full Laplacian of the de ...
Floricel, Remus +2 more
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∗-Ricci Tensor on α-Cosymplectic Manifolds
Advances in Mathematical Physics, 2022 In this paper, we study α-cosymplectic manifold M admitting ∗-Ricci tensor. First, it is shown that a ∗-Ricci semisymmetric manifold M is ∗-Ricci flat and a ϕ-conformally flat manifold M is an η-Einstein manifold. Furthermore, the ∗-Weyl curvature tensor
M. R. Amruthalakshmi +3 more
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On the Geometry of Three-dimensional Pseudo-Riemannian Homogeneous Spaces. II [PDF]
Известия Саратовского университета. Новая серия: Математика. Механика. Информатика, 2020 The problem of establishing links between the curvature and the topological structure of a manifold is one of the important problems of the geometry. In general, the purpose of the research of manifolds of various types is rather complicated.
Mozhey, Natal’ya Pavlovna
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A Note on the Geometry of RW Space-Times
Mathematics, 2023 A conformally flat GRW space-time is a perfect fluid RW space-time. In this note, we investigated the influence of many differential curvature conditions, such as the existence of recurrent and semi-symmetric curvature tensors.
Sameh Shenawy +2 more
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Ricci curvature and betti numbers [PDF]
Journal of Geometric Analysis, 1997 18pages ...
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