LENGTH functions on a group G which come from actions on R-trees [20,29,10,3,37] and spaces of such length functions have been of central importance in combinatorial group theory in recent years. We… Expand

This investigation synthesized research from several related areas to produce a model of resistance to persuasion based upon variables not considered by earlier congruity and inoculation models.… Expand

On considere des automorphismes φ:F n →F n , ou F n =F(a 1 ,…,a n ) est le groupe libre de base a 1 ,a 2 ,…,a n (n≥2). On compose un champ vectoriel sur un graphe D(φ). On introduit des aretes… Expand

Regular neighborhoods of polyhedra in manifolds have been discussed in many papers, most notably, in the present context, in [W], [H-Z], [H] and [S]. We study regular neighborhoods of X mod Y in Z… Expand

In their basic paper [C-M] Culler and Morgan emphasize the analogy between conjugacy classes of representations of a group G in SO ℝ + (2,1) = PSL(2,ℝ), and translation length functions on G which… Expand

We prove that the natural map G! b G ,w here Gis a torsion-free group and b G is obtained by adding a new generator t and a new relator w, is surjective only if w is conjugate to gt or gt 1 where g2… Expand