Results 131 to 140 of about 2,217 (169)

A Class of Homogeneous Einstein Manifolds*

Chinese Annals of Mathematics, Series B, 2006
Let \(G\) be a compact connected simple Lie group with simple Lie algebra \(g\), \(\theta\) and \(\tau\) are two involutions of \(G\) such that \(\theta \tau=\tau \theta\). Let \(K=\{X\in G\,,\,\theta(X)=X\}\), \(K^{\prime}=\{X\in G\), \(\tau(X)=X\}\), and \(K^+=K\cap K^{\prime}\).
Kang, Yifang, Liang, Ke
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Weyl manifolds and Einstein-Weyl manifolds

Commentarii mathematici Universitatis Sancti Pauli = Rikkyo Daigaku sugaku zasshi, 1993
The author sets out to clarify the true character of some fundamental invariants in Weyl geometry and then constructs some types of Einstein- Weyl manifolds. A Weyl structure \(W\) on a manifold \(M\) consists of a Riemannian metric \(g\) and a 1-form \(\phi\) on \(M\).
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On pseudo quasi-Einstein manifolds

Periodica Mathematica Hungarica, 2009
A type of non-flat semi-Riemannian manifolds, called pseudo quasi-Einstein manifold, is introduced and studied in detail. The quasi-Einstein manifolds are well-known, and are relevant in general relativity: Robertson-Walker spacetimes belong to this class.
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Spin Holonomy of Einstein Manifolds

Communications in Mathematical Physics, 1999
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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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η-Einstein nearly Kenmotsu manifolds

Asian-European Journal of Mathematics, 2019
In this paper, we showed that an [Formula: see text]-Einstein nearly Kenmotsu manifold with projective curvature tensor [Formula: see text], and conharmonic curvature tensor [Formula: see text], satisfy the conditions [Formula: see text] and [Formula: see text], respectively.
Tekin, Pelin, Aktan, Nesip
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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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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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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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