Results 11 to 20 of about 63,399 (238)
The Ricci tensor of almost parahermitian manifolds [PDF]
Annals of Global Analysis and Geometry, 2017 36 pages; v2, minor corrections, two references added, presentation improved; v3, clarified definition of \overline{F}; corrected coefficients in Proposition 12, fixed typos in statements of Lemma 13 and Theorem ...
Diego Conti, Federico A. Rossi
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The Ricci tensor of a gradient Ricci soliton with harmonic Weyl tensor [PDF]
In this article, we give a new proof of a result due to J. Kim, which states that the Ricci tensor of a gradient Ricci soliton with dimension $n \geq 4$ and harmonic Weyl tensor has at most three distinct eigenvalues. This result constitutes an essential step in the classification of such manifolds, originally established by J. Kim in dimension $4$ and
Valter Borges +2 more
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Comparison geometry for the Bakry-Emery Ricci tensor [PDF]
Journal of Differential Geometry, 2009 For Riemannian manifolds with a measure $(M,g, e^{-f} dvol_g)$ we prove mean curvature and volume comparison results when the $\infty$-Bakry-Emery Ricci tensor is bounded from below and $f$ is bounded or $\partial_r f$ is bounded from below, generalizing the classical ones (i.e. when $f$ is constant). This leads to extensions of many theorems for Ricci
Guofang Wei, William Wylie
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Myers’ type theorem with the Bakry–Émery Ricci tensor [PDF]
Annals of Global Analysis and Geometry, 2018 A reference added, minor typos corrected. Accepted by Ann. Glob.
Jia-Yong Wu
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Symplectic Yang-Mills theory, Ricci tensor, and connections [PDF]
Calculus of Variations and Partial Differential Equations, 2006 A Yang-Mills theory in a purely symplectic framework is developed. The corresponding Euler-Lagrange equations are derived and first integrals are given. We relate the results to the work of Bourgeois and Cahen on preferred symplectic connections.
Katharina Habermann +2 more
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The ∗-Ricci Operator on Hopf Real Hypersurfaces in the Complex Quadric
Mathematics, 2022 We study the ∗-Ricci operator on Hopf real hypersurfaces in the complex quadric. We prove that for Hopf real hypersurfaces in the complex quadric, the ∗-Ricci tensor is symmetric if and only if the unit normal vector field is singular.
Rongsheng Ma, Donghe Pei
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Mathematics, 2023 The purpose of the present paper is to study the complete lifts of a QSNMC from an LP-Sasakian manifold to its tangent bundle. The lifts of the curvature tensor, Ricci tensor, projective Ricci tensor, and lifts of Einstein manifold endowed with QSNMC in ...
Rajesh Kumar +3 more
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Muscle Imaging in Inclusion Body Myositis: Refinement of MRI Criteria and Insights Into Upper Body Involvement. [PDF]
J Cachexia Sarcopenia MuscleABSTRACT Background The diagnosis of inclusion body myositis (IBM) can be delayed because of its heterogeneous clinical presentation and the lack of specific biomarkers. Muscle imaging has gained increasing relevance over the past decade and is now included among the supportive criteria in the international diagnostic guidelines.
Torchia E +15 more
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Non-holonomic Kenmotsu manifolds equipped with generalized Tanaka — Webster connection
Дифференциальная геометрия многообразий фигур, 2021 А non-holonomic Kenmotsu manifold equipped with a connection analogous to the generalized Tanaka — Webster connection, is considered. The studied connection is obtained from the generalized Tanaka — Webster connection by replacing the first structural ...
A.V. Bukusheva
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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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