Results 271 to 280 of about 75,365 (285)

Super $$\eta $$-Einstein Manifolds

Results in Mathematics
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Pablo Alegre, Alfonso Carriazo, Jong Taek Cho   +2 more
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Compact standard periodic einstein manifolds

Siberian Mathematical Journal, 1992
A Riemannian manifold \(M\) with a metric \(g\) is Einstein if its metric \(g\) satisfies the equation: \(\text{Ric}(g)=Cg\), where Ric is the Ricci tensor of \(M\) and \(C\) is a constant. Let \(G\) be a connected, compact simple Lie group and \(H\) its closed simple subgroup with \(G/H\) simply connected. The homogeneous Riemannian metric induced on \
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Generalized Einstein manifolds

Journal of Geometry and Physics, 1995
The geometrization of physics, especially regarding the equations of electromagnetism and gravitation in general relativity, has been a vital problem of investigation for a long time. A. Einstein himself devoted the last several years of his life to realize this dream without success. However, taking grant of two axioms proposed by \textit{D. Hilbert} [
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Kähler–Einstein Manifolds

2018
A Kahler manifold (M, g) is Einstein when there exists \(\lambda \in \mathbb {R}\) such that ρ = λω, where ω is the Kahler form associated to g and ρ is its Ricci form. The constant λ is called the Einstein constant and it turns out that λ = s∕2n, where s is the scalar curvature of the metric g and n the complex dimension of M (as a general reference ...
Andrea Loi, Michela Zedda
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Noncompact Homogeneous Einstein 5-Manifolds

Geometriae Dedicata, 2005
Let \(M^n\) be a simply connected \(n\)-dimensional homogeneous Einstein manifold. It is well known that \(M\) is a space of constant curvature if \(n \in \{2,3\}\). For \(n=4\) \textit{G. R. Jensen} proved in [J. Differ. Geom. 3, 309--349 (1969; Zbl 0194.53203)] that \(M\) is a symmetric space.
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ALMOST EINSTEIN-HERMITIAN MANIFOLDS

JP Journal of Geometry and Topology
In this paper, we show that every almost Einstein-Hermitian 4-manifold (i.e., almost Hermitian 4-manifold with -invariant Ricci tensor and harmonic Weyl tensor) is either Einstein or Hermitian. Consequently, we obtain that any almost Einstein-Hermitian 4-manifold which is not Einstein must be Hermitian and that every almost Einstein-Hermitian 4 ...
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Twistorial Examples of *-Einstein Manifolds

Annals of Global Analysis and Geometry, 2001
The purpose of the present paper is to study the 6-dimensional twistor space \(Z\) of an oriented 4-dimensional Riemannian manifold \(M\) as an example of almost Hermitian \(*\)-Einstein manifolds. The twistor space \(Z\) of \(M\) admits in a natural way a one-parameter family of Riemannian metrics \(h_t\), compatible with its two canonical almost ...
Davidov, Johann, Grantcharov, Gueo, Muškarov, Oleg   +2 more
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On Strongly Inhomogeneous Einstein Manifolds

Bulletin of the London Mathematical Society, 1996
The present authors constructed in [J. Reine Angew. Math. 455, 183-220 (1994)] inhomogeneous Einstein metrics of positive scalar curvature on compact simply connected 3-Sasakian manifolds \((S(p),g(p))\) in dimension \(4n-5\) for all \(n\geq 3\).
Boyer, Charles P., Galicki, Krzysztof, Mann, Benjamin M.   +2 more
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Four-Dimensional Almost Kähler Einstein and *-Einstein Manifolds

Geometriae Dedicata, 1998
The Goldberg conjecture [\textit{S. I. Goldberg}, Proc. Am. Math. Soc. 21, 96-100 (1969; Zbl 0174.25002)] states that a compact Einstein almost Kähler manifold is necessarily Kähler. It has been proved that the conjecture holds true if the scalar curvature is nonnegative [\textit{K. Sekigawa}, J. Math. Soc.
Oguro, Takashi, Sekigawa, Kouei
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Compact Homogeneous Einstein 7-Manifolds

Geometriae Dedicata, 2004
English translation of Mat. Tr. 3, No. 2, 129-145 (2000; Zbl 0966.53031).
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