Stabilization for the automorphisms of free groups with boundaries.
Stable actions of groups on real trees.
Stable rational cohomology of automorphism groups of free groups and the integral cohomology of moduli spaces of graphs.
It is not known whether or not the stable rational cohomology groups H*(Aut(F∞);Q) always vanish (see Hatcher in [5] and Hatcher and Vogtmann in [7] where they pose the question and show that it does vanish in the first 6 dimensions). We show that either the rational cohomology does not vanish in certain dimensions, or the integral cohomology of a moduli space of pointed graphs does not stabilize in certain other dimensions. Similar results are stated for groups of outer automorphisms. This yields...
Stable Teichmüller quasigeodesics and ending laminations.
State-sum invariants of knotted curves and surfaces from quandle cohomology.
Straightening cell decompositions of cusped hyperbolic 3-manifolds
Let be an oriented cusped hyperbolic 3-manifold and let be a topological ideal triangulation of . We give a characterization for to be isotopic to an ideal geodesic triangulation; moreover we give a characterization for to flatten into a partially flat triangulation. Finally we prove that straightening combinatorially equivalent topological ideal cell decompositions gives the same geodesic decomposition, up to isometry.
Strategies towards a disproof of the general Andrews-Curtis conjecture.
Strong Band sum and dichromatic invariants.
Strong surjectivity of maps from 2-complexes into the 2-sphere
Given a model 2-complex K P of a group presentation P, we associate to it an integer matrix ΔP and we prove that a cellular map f: K P → S 2 is root free (is not strongly surjective) if and only if the diophantine linear system ΔP Y = (f) has an integer solution, here (f)is the so-called vector-degree of f
Strongly geodesically automatic groups are hyperbolic.
Strongly Invertible Knots Have Property R
Strongly invertible knots, rational-fold branched coverings, and hyperbolic spatial graphs.
Structure and Regidity in Hyperbolic Groups. I.
Structure of geodesics in the Cayley graph of infinite Coxeter groups
Let (W,S) be a Coxeter system such that no two generators in S commute. Assume that the Cayley graph of (W,S) does not contain adjacent hexagons. Then for any two vertices x and y in the Cayley graph of W and any number k ≤ d = dist(x,y) there are at most two vertices z such that dist(x,z) = k and dist(z,y) = d - k. Allowing adjacent hexagons, but assuming that no three hexagons can be adjacent to each other, we show that the number of such intermediate vertices at a given distance from x and y...
Structures affines et projectives sur les surfaces complexes
Une structure complexe affine (resp. projective) sur une surface complexe est la donnée d’un atlas de cartes à valeur dans (resp. ) à changements de cartes localement constants dans le groupe affine (resp. le groupe ). Dans cet article nous classifions les surfaces complexes affines et calculons, à surface complexe fixée, l’espace de déformation des structures complexes affines sur compatibles avec sa structure analytique. Nous montrons aussi que toute structure projective sur une surface...
Structures on Manifolds Defined by Cross-Sections.
Studying links via closed braids IV: composite links and split links.
SU (2)-representation spaces for two-bridge knot groups.
Subgroup separability and 3-manifold groups.
Subgroups of Knot Groups.