Wise's w-cycle conjecture and homological coherence for one-relator groups
Lars Louder (University College London)
Wednesday 18th February, 2015 16:00-17:00 Maths 516
A two-complex X has non-positive immersions if, for every immersion Y->X, Y compact, either \chi(Y)<=0 or Y has trivial fundamental group. In this talk I'll show that presentation complexes for one-relator groups have non-positive immersions, and, as a corollary, that finitely generated subgroups of one-relator groups have finite second betti numbers. This is joint work with Henry Wilton.