Results 21 to 30 of about 886 (48)
A note on the uniqueness of the canonical connection of a naturally reductive space [PDF]
, 2012 We extend the result in J. Reine Angew. Math. 664, 29-53, to the non-compact case. Namely, we prove that the canonical connection on a simply connected and irreducible naturally reductive space is unique, provided the space is not a sphere, a compact Lie
Olmos, Carlos, Reggiani, Silvio
core +3 more sources
Contact metric manifolds with large automorphism group and (κ, µ)-spaces
Complex Manifolds, 2019 We discuss the classifiation of simply connected, complete (κ, µ)-spaces from the point of view of homogeneous spaces. In particular, we exhibit new models of (κ, µ)-spaces having Boeckx invariant -1.
Lotta Antonio
doaj +1 more source
A condition for a perfect-fluid space-time to be a generalized Robertson-Walker space-time [PDF]
, 2016 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
core +2 more sources
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
doaj +1 more source
Corrigendum for "A geometric proof of the Karpelevich-Mostow theorem" [PDF]
, 2016 Corollary 2.3 in our paper "A geometric proof of the Karpelevich-Mostow theorem", Bull. Lond. Math. Soc. 41 (2009), no. 4, 634-638, is false. Here we give a counterexample and show how to avoid the use of this corollary to give a simpler proof of ...
Di Scala, Antonio J., Olmos, Carlos
core
Examples of naturally reductive pseudo-Riemannian Lie groups
, 2011 We provide examples of naturally reductive pseudo-Riemannian spaces, in particular an example of a naturally reductive pseudo-Riemannian 2-step nilpotent Lie group $(N, _N)$, such that $_N$ is invariant under a left action and for which the center is ...
Ovando, Gabriela P.
core +1 more source
Projectively induced rotation invariant K\"ahler metrics
, 2016 We classify K\"ahler-Einstein manifolds which admit a K\"ahler immersion into a finite dimensional complex projective space endowed with the Fubini-Study metric, whose codimention is not greater than 3 and whose metric is rotation invariant.Comment: 9 ...
Salis, Filippo
core +1 more source
A geometric proof of the Karpelevich-Mostow's theorem
, 2007 In this paper we give a geometric proof of the Karpelevich's theorem that asserts that a semisimple Lie subgroup of isometries, of a symmetric space of non compact type, has a totally geodesic orbit.
Di Scala, Antonio J., Olmos, Carlos
core +1 more source
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
doaj +1 more source
Preferred Parameterisations on Homogeneous Curves [PDF]
, 2003 We show how to specify preferred parameterisations on a homogeneous curve in an arbitrary homogeneous space. We apply these results to limit the natural parameters on distinguished curves in parabolic geometries.Comment: 10 ...
Eastwood, Michael, Slovak, Jan
core +1 more source