Results 51 to 60 of about 473,950 (309)
On geometry of sub-Riemannian η-Einstein manifolds
Дифференциальная геометрия многообразий фигур, 2019 On a sub-Riemannian manifold of contact type a connection with torsion is considered, called in the work a Ψ-connection. A Ψ-connection is a particular case of an N-connection.
S. Galaev
doaj +1 more source
On gradient η-Einstein solitons
, 2018 If the potential vector field of an η-Einstein soliton is of gradient type, using Bochner formula, we derive from the soliton equation a nonlinear second order PDE.
A. Blaga
semanticscholar +1 more source
Conformally Einstein–Maxwell Kähler metrics and structure of the automorphism group [PDF]
Mathematische Zeitschrift, 2017 Let (M, g) be a compact Kähler manifold and f a positive smooth function such that its Hamiltonian vector field $$K = J\mathrm {grad}_g f$$K=Jgradgf for the Kähler form $$\omega _g$$ωg is a holomorphic Killing vector field. We say that the pair (g, f) is
A. Futaki, Hajime Ono
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Einstein almost cok��hler manifolds
, 2014 We study an odd-dimensional analogue of the Goldberg conjecture for compact Einstein almost K hler manifolds. We give an explicit non-compact example of an Einstein almost cok hler manifold that is not cok hler. We prove that compact Einstein almost cok hler manifolds with non-negative $*$-scalar curvature are cok hler (indeed, transversely Calabi-
CONTI, DIEGO, Fernández, M.
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On $K$-contact Einstein manifolds
Novi Sad Journal of Mathematics, 2016 In this paper, we investigate K-contact Einstein manifolds satisfying the conditions RC = Q(S,C), where C is the conformal curvature tensor and R the Riemannian curvature tensor. Next we consider K-contact Einstein manifolds satisfying the curvature condition C.S = 0, where S is the Ricci tensor.
De, U. C., Mandal, Krishanu
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Kähler–Ricci flow, Kähler–Einstein metric, and K–stability [PDF]
Geometry and Topology, 2015 We prove the existence of Kahler-Einstein metric on a K-stable Fano manifold using the recent compactness result on Kahler-Ricci flows. The key ingredient is an algebro-geometric description of the asymptotic behavior of Kahler-Ricci flow on Fano ...
Xiuxiong Chen, Song Sun, B. Wang
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Decomposition of geometric perturbations
, 2008 For an infinitesimal deformation of a Riemannian manifold, we prove that the scalar, vector, and tensor modes in decompositions of perturbations of the metric tensor, the scalar curvature, the Ricci tensor, and the Einstein tensor decouple if and only if
Arnowitt +9 more
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Optimal bounds for the volumes of Kähler-Einstein Fano manifolds [PDF]
, 2015 :We show that any $n$-dimensional Ding semistable Fano manifold $X$ satisfies that the anti-canonical volume is less than or equal to the value $(n+1)^n$.
Kento Fujita
semanticscholar +1 more source
Sasaki–Einstein Manifolds and Volume Minimisation [PDF]
Communications in Mathematical Physics, 2008 We study a variational problem whose critical point determines the Reeb vector field for a Sasaki-Einstein manifold. This extends our previous work on Sasakian geometry by lifting the condition that the manifolds are toric. We show that the Einstein-Hilbert action, restricted to a space of Sasakian metrics on a link L in a Calabi-Yau cone X, is the ...
Martelli D., Sparks J., Yau S. -T.
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Anti-de Sitter massless scalar field spacetimes in arbitrary dimensions
, 2012 We consider $d$-dimensional static spacetimes in Einstein gravity with a cosmological constant in the presence of a minimally coupled massless scalar field.
Cristián Martínez +5 more
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