Amenable Groups and Stabilizers of Measures on the Boundary of a Hadamard Manifold.
Amenable hyperbolic groups
We give a complete characterization of the locally compact groups that are non elementary Gromov-hyperbolic and amenable. They coincide with the class of mapping tori of discrete or continuous one-parameter groups of compacting automorphisms. We moreover give a description of all Gromov-hyperbolic locally compact groups with a cocompact amenable subgroup: modulo a compact normal subgroup, these turn out to be either rank one simple Lie groups, or automorphism groups of semiregular trees acting doubly...
Amenable, transitive and faithful actions of groups acting on trees
We study under which condition an amalgamated free product or an HNN-extension over a finite subgroup admits an amenable, transitive and faithful action on an infinite countable set. We show that such an action exists if the initial groups admit an amenable and almost free action with infinite orbits (e.g. virtually free groups or infinite amenable groups). Our result relies on the Baire category Theorem. We extend the result to groups acting on trees.
Amorces de la chirurgie en dimension quatre : un exotique
Ample Divisors on Fine Moduli Spaces on the Projective Plane.
An Abelian Quotient of the Mapping Class Group ...g.
An acyclic extension of the braid group.
An Algebraic Classification of some Knots of Codimension Two.
An algebraic construction of the generic singularities of Boardman-Thom
An algebraic group associated to an ergodic diffeomorphism
An Algebraic Model for G-Simple Homotopy Types.
An algorithm of finding planar surfaces in three-manifolds.
An algorithm to detect laminar 3-manifolds.
An almost-integral universal Vassiliev invariant of knots.
An analogue of covering space theory for ranked posets.
An analytic interpretation of real dimension subgroups.
An analytic proof of Novikov's theorem on rational Pontrjagin classes
An annulus theorem for suspension spheres
An application of principal bundles to coloring of graphs and hypergraphs
An interesting connection between the chromatic number of a graph and the connectivity of an associated simplicial complex , its “neighborhood complex”, was found by Lovász in 1978 (cf. L. Lovász [J. Comb. Theory, Ser. A 25, 319-324 (1978; Zbl 0418.05028)]). In 1986 a generalization to the chromatic number of a -uniform hypergraph , for an odd prime, using an associated simplicial complex , was found ([N. Alon, P. Frankl and L. Lovász, Trans. Am. Math. Soc. 298, 359-370 (1986; Zbl 0605.05033)],...
An approach to automorphisms of free groups and braids via transvections.