Results 41 to 50 of about 169,909 (330)
Generalized Quasi-Einstein Manifolds in Contact Geometry
Mathematics, 2020 In this study, we investigate generalized quasi-Einstein normal metric contact pair manifolds. Initially, we deal with the elementary properties and existence of generalized quasi-Einstein normal metric contact pair manifolds.
İnan Ünal
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On Einstein, Hermitian 4-manifolds [PDF]
Journal of Differential Geometry, 2012 Let (M,h) be a compact 4-dimensional Einstein manifold, and suppose that h is Hermitian with respect to some complex structure J on M. Then either (M,J,h) is Kaehler-Einstein, or else, up to rescaling and isometry, it is one of the following two exceptions: the Page metric on CP2 # (-CP2), or the Einstein metric on CP2 # 2 (-CP2) constructed in Chen ...
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Quaternionic contact Einstein manifolds [PDF]
Mathematical Research Letters, 2016 The main result is that the qc-scalar curvature of a seven dimensional quaternionic contact Einstein manifold is a constant. In addition, we characterize qc-Einstein structures with certain flat vertical connection and develop their local structure equations. Finally, regular qc-Ricci flat structures are shown to fibre over hyper-Kahler manifolds.
Ivan Minchev +2 more
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AASLD practice guidance on drug, herbal, and dietary supplement–induced liver injury
, 2022 Hepatology, EarlyView.
Robert J. Fontana +6 more
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Contact-Complex Riemannian Submersions
Mathematics, 2021 A submersion from an almost contact Riemannian manifold to an almost Hermitian manifold, acting on the horizontal distribution by preserving both the metric and the structure, is, roughly speaking a contact-complex Riemannian submersion. This paper deals
Cornelia-Livia Bejan +2 more
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Ricci soliton and Ricci almost soliton within the framework of Kenmotsu manifold
Karpatsʹkì Matematičnì Publìkacìï, 2019 First, we prove that if the Reeb vector field $\xi$ of a Kenmotsu manifold $M$ leaves the Ricci operator $Q$ invariant, then $M$ is Einstein. Next, we study Kenmotsu manifold whose metric represents a Ricci soliton and prove that it is expanding ...
A. Ghosh
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Quarter-Symmetric Metric Connection on a Cosymplectic Manifold
Mathematics, 2023 We study the quarter-symmetric metric A-connection on a cosymplectic manifold. Observing linearly independent curvature tensors with respect to the quarter-symmetric metric A-connection, we construct the Weyl projective curvature tensor on a cosymplectic
Miroslav D. Maksimović +1 more
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Isotropic quasi-Einstein manifolds [PDF]
Classical and Quantum Gravity, 2019 We investigate the local structure of four-dimensional Lorentzian quasi-Einstein manifolds under conditions on the Weyl tensor. We show that if the Weyl tensor is harmonic and the potential function preserves this harmonicity then, in the isotropic case, the manifold is necessarily a $pp$-wave. Using the quasi-Einstein equation, further conclusions are
M Brozos-Vázquez +2 more
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Kenmotsu 3-manifolds and gradient solitons
Karpatsʹkì Matematičnì Publìkacìï, 2023 The aim of this article is to characterize a Kenmotsu 3-manifold whose metric is either a gradient Yamabe soliton or gradient Einstein soliton. It is proven that in both cases this manifold is reduced to the manifold of constant sectional curvature ...
F. Mofarreh, U.C. De
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The spectral Einstein functional and the noncommutative residue for manifolds with boundary [PDF]
arXiv, 2022 In this paper, we define the spectral Einstein functional associated with the Dirac operator for manifolds with boundary. And we give the proof of Kastler-Kalau-Walze type theorem for the spectral Einstein functional associated with the Dirac operator on 4-dimensional manifolds with boundary.
arxiv