• 検索結果がありません。

Metrics with homogeneous geodesics on ag manifolds

N/A
N/A
Protected

Academic year: 2022

シェア "Metrics with homogeneous geodesics on ag manifolds"

Copied!
1
0
0

読み込み中.... (全文を見る)

全文

(1)

Dmitri Alekseevsky, Andreas Arvanitoyeorgos

Metrics with homogeneous geodesics on ag manifolds

Comment.Math.Univ.Carolinae 43,2 (2002) 189-199.

Abstract: A geodesic of a homogeneous Riemannian manifold (M =G/K, g) is called homogeneous if it is an orbit of an one-parameter subgroup of G. In the case whenM =G/H is a naturally reductive space, that is theG-invariant metric g is defined by some non degenerate biinvariant symmetric bilinear form B, all geodesics ofM are homogeneous. We consider the case whenM =G/K is a flag manifold, i.e. an adjoint orbit of a compact semisimple Lie group G, and we give a simple necessary condition that M admits a non-naturally reductive invariant metric with homogeneous geodesics. Using this, we enumerate flag manifolds of a classical Lie groupGwhich may admit a non-naturally reductiveG-invariant metric with homogeneous geodesics.

Keywords: homogeneous Riemannian spaces, homogeneous geodesics, flag mani- folds

AMS Subject Classification: Primary 53C22, 53C30; Secondary 14M15

1

参照

関連したドキュメント

Thus JC/a v is a defining system of invariant eigendistributions and the Fourier transform of Jr These systems wilt be known to be regular holo- nomic.. Here

Yang, “On the norm of a certain self-adjiont integral operator and applications to bilinear integral inequalities,” to appear in Taiwanese Journal of Mathematics..

To obtain the identity for the punctured torus choose a separating simple geodesic δ and consider a sequence of metrics on M such that the length of δ tends to 0 (one says that δ

(1) Let M be a closed Riemann surface of genus g and assume that M has a set F of 2g simple closed geodesics such that all elements of F intersect in the same two points A and B

Also, we obtain the best possible constants in the case of conjugate parameters when the parameters satisfy appropriate conditions.. We also compare our results with some

Abstract: For a compact connected semisimple Lie group G we shall prove two results (both related with Singhof’s paper [13]) on the Lusternik-Schnirelmann cat- egory of the

We apply the criterion to some particular cases where M is parallelizable, for instance M = S 7 or a compact simple Lie group G with a bi-invariant metric, and E is the trivial

When G/H carries a G-invariant measure, Γ is called a lattice in G/H iff Γ acts on G/H freely and properly discontinuously so that Γ\G/H is of finite volume; a non-uniform lattice