An Integrability Condition for Simple Lie Groups II [PDF]
It is shown that a simple Lie group $G$ ($ \neq {\rm SL}_2$) can be locally characterised by an integrability condition on an $\operatorname{Aut}(\mathfrak{g})$ structure on the tangent bundle, where $\operatorname{Aut}(\mathfrak{g})$ is the automorphism
Min-Oo, Maung
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Contact manifolds, Lagrangian Grassmannians and PDEs
Complex Manifolds, 2018 In this paper we review a geometric approach to PDEs. We mainly focus on scalar PDEs in n independent variables and one dependent variable of order one and two, by insisting on the underlying (2n + 1)-dimensional contact manifold and the so-called ...
Eshkobilov Olimjon +3 more
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A remark on the Bismut-Ricci form on 2-step nilmanifolds [PDF]
In this note we observe that on a 2-step nilpotent Lie group equipped with a left-invariant SKT structure the (1,1)-part of the Bismut-Ricci form is seminegative definite.
Pujia, Mattia, Vezzoni, Luigi
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On generalized G2-structures and T-duality [PDF]
This is a short note on generalized G2-structures obtained as a consequence of a T-dual construction given in del Barco et al. (2017). Given classical G2-structure on certain seven dimensional manifolds, either closed or co-closed, we obtain integrable ...
del Barco, Viviana Jorgelina +1 more
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On the smallest Laplace eigenvalue for naturally reductive metrics on compact simple Lie groups [PDF]
Eldredge, Gordina and Saloff-Coste recently conjectured that, for a given compact connected Lie group $G$, there is a positive real number $C$ such that $\lambda_1(G,g)\operatorname{diam}(G,g)^2\leq C$ for all left-invariant metrics $g$ on $G$.
Lauret, Emilio Agustin
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On the Existence of a Codimension 1 Completely Integrable Totally Geodesic Distribution on a Pseudo-Riemannian Heisenberg Group [PDF]
In this note we prove that the Heisenberg group with a left-invariant pseudo-Riemannian metric admits a completely integrable totally geodesic distribution of codimension 1.
Batat, Wafaa, Rahmani, Salima
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Geodesics and magnetic curves in the 4-dim almost Kähler model space F4
Complex ManifoldsWe study geodesics and magnetic trajectories in the model space F4{{\rm{F}}}^{4}. The space F4{{\rm{F}}}^{4} is isometric to the 4-dim simply connected Riemannian 3-symmetric space due to Kowalski. We describe the solvable Lie group model of F4{{\rm{F}}}^
Erjavec Zlatko, Inoguchi Jun-ichi
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Homogeneous Riemannian Structures on Berger 3-Spheres [PDF]
13 pages.-- MSC2000 codes: 53C30, 53C25.The homogeneous Riemannian structures on the 3-dimensional Berger spheres, their corresponding reductive decompositions and the associated groups of isometries are obtained.
Grosshans, Frank D. +2 more
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A condition for a perfect-fluid space-time to be a generalized Robertson-Walker space-time [PDF]
A perfect-fluid space-time of dimension n>3 with 1) irrotational velocity vector field, 2) null divergence of the Weyl tensor, is a generalised Robertson-Walker space-time with Einstein fiber. Condition 1) is verified whenever pressure and energy density
De, Uday Chand +2 more
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III-harmonic Curves in SL2ℝ˜\widetilde {{\rm{S}}{{\rm{L}}_2}\mathbb{R}} Space
Annals of the West University of Timisoara: Mathematics and Computer ScienceSome work has been done in the study of non-geodesic III-harmonic curves in some model spaces. In this paper, we study III-harmonic curves in SL2ℝ˜\widetilde {{\rm{S}}{{\rm{L}}_2}\mathbb{R}} space. We give necessary and su cient conditions for helices to
Senoussi Bendehiba
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