Les groupes oscillateurs et leurs reseaux.
Levi-Curvature of Manifolds with a Stein Rational Fibration.
Local reflexion spaces
A reflexion space is generalization of a symmetric space introduced by O. Loos in [4]. We generalize locally symmetric spaces to local reflexion spaces in the similar way. We investigate, when local reflexion spaces are equivalently given by a locally flat Cartan connection of certain type.
Martin boundary for homogeneous riemannian manifolds of negative curvature at the bottom of the spectrum.
In this paper we treat noncoercive operators on simply connected homogeneous manifolds of negative curvature.
Metric Entropy of Homogeneous Spaces
For a precompact subset K of a metric space and ε > 0, the covering number N(K,ε) is defined as the smallest number of balls of radius ε whose union covers K. Knowledge of the metric entropy, i.e., the asymptotic behaviour of covering numbers for (families of) metric spaces is important in many areas of mathematics (geometry, functional analysis, probability, coding theory, to name a few). In this paper we give asymptotically correct estimates for covering numbers for a large class of homogeneous...
Metrics with homogeneous geodesics on flag manifolds
A geodesic of a homogeneous Riemannian manifold is called homogeneous if it is an orbit of an one-parameter subgroup of . In the case when is a naturally reductive space, that is the -invariant metric is defined by some non degenerate biinvariant symmetric bilinear form , all geodesics of are homogeneous. We consider the case when is a flag manifold, i.eȧn adjoint orbit of a compact semisimple Lie group , and we give a simple necessary condition that admits a non-naturally reductive...
Minimal cones and the spherical Bernstein prob-lem. III.
Moduli for spherical maps and minimal immersions of homogeneous spaces.
Nambu-Poisson Tensors on Lie Groups
First as an application of the local structure theorem for Nambu-Poisson tensors, we characterize them in terms of differential forms. Secondly left invariant Nambu-Poisson tensors on Lie groups are considered.
Naturally reductive homogeneous spaces and generalized Heisenberg groups
Naturally reductive homogeneous -metric spaces
In the present paper we study naturally reductive homogeneous -metric spaces. We show that for homogeneous -metric spaces, under a mild condition, the two definitions of naturally reductive homogeneous Finsler space, given in the literature, are equivalent. Then, we compute the flag curvature of naturally reductive homogeneous -metric spaces.
New Einstein metrics on which are non-naturally reductive
We prove that there are at least two new non-naturally reductive invariant Einstein metrics on . It implies that every compact simple Lie group ...
New Examples of Weakly Symmetric Spaces.
Nilmanifolds with Carnot-Carathéodory metrics.
Nilvariétés projectives.
Noncoercive differential operators on homogeneous manifolds of negative curvature and their Green functions
We obtain upper and lower estimates for the Green function for a second order noncoercive differential operator on a homogeneous manifold of negative curvature.
Non-commutative Gauss map
Nonhomogeneous Riemannian 3-manifolds with distinct constant Ricci eigenvalues
We extend a construction by K. Yamato [Ya] to obtain new explicit examples of Riemannian 3-manifolds as in the title. Some of these examples have an interesting geometrical interpretation.
Non-standard Einstein extensions of five dimensional nilpotent metric Lie algebras.
On 3-symmetric Riemannian spaces of solvable type