A Polish AR-Space with no Nontrivial Isotopy
The Polish space Y constructed in [vM1] admits no nontrivial isotopy. Yet, there exists a Polish group that acts transitively on Y.
Absolute retracts as factors of normed linear spaces
Actions de groupes sur les -variétés non séparées et feuilletages de codimension un
Actions of the group of homeomorphisms of the circle on surfaces
We describe all the group morphisms from the group of orientation-preserving homeomorphisms of the circle to the group of homeomorphisms of the annulus or of the torus.
Algebraic Transformation Groups and Representation.
Area preserving twist homeomorphism of the annulus.
Closed curves and circle homomorphisms in groups of diffeomorphisms
Commensurations of the Johnson kernel.
Convergence Structures on Homeomorphism Groups.
Deformation of Homeomorphismus on Stratified Sets
Dual topology of a nilpotent Lie group
Equivariant periodicity for abelian group action.
Factorizable groups of homeomorphisms
Fibrations in symplectic topology.
Flots d'Anosov sur les variétés graphées au sens de Waldhausen
Cet article est consacré à l’étude d’une large classe de flots d’Anosov sur les variétés graphées. Nous établissons un résultat général à propos des plongements de variétés de Seifert dans les variétés de dimension 3 admettant un flot d’Anosov produit, généralisant ainsi un résultat de E. Ghys. Nous montrons que, à isotopie près, la restriction du feuilletage unidimensionnel défini par le flot à l’image de ce plongement est topologiquement conjugué à un morceau de flot géodésique privé d’un nombre...
Fundamental group of with no circle action
We show that can be nontrivial for that does not admit any symplectic circle action.
Generic properties of the rotation number of one-parameter diffeomorphisms of the circle
Groups of real analytic diffeomorphisms of the circle with a finite image under the rotation number function
We consider groups of orientation-preserving real analytic diffeomorphisms of the circle which have a finite image under the rotation number function. We show that if such a group is nondiscrete with respect to the -topology then it has a finite orbit. As a corollary, we show that if such a group has no finite orbit then each of its subgroups contains either a cyclic subgroup of finite index or a nonabelian free subgroup.
Halbeinfache Automorphismengruppen von vierdimensionalen stabilen Ebenen sind quasi-einfach.
Homeomorphic conjugates of Fuchsian groups.