Thompson ’ S Group F Is Not Almost Convex
نویسنده
چکیده
We show that Thompson’s group F does not satisfy Cannon’s almost convexity condition AC(n) for any integer n in the standard finite two generator presentation. To accomplish this, we construct a family of pairs of elements at distance n from the identity and distance 2 from each other, which are not connected by a path lying inside the n-ball of length less than k for increasingly large k. Our techniques rely upon Fordham’s method for calculating the length of a word in F and upon an analysis of the generators’ geometric actions on the tree pair diagrams representing elements of F .
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