The homology of Richard Thompson’s group F

نویسنده

Ken Brown

چکیده

Let F be Thompson’s group, with presentation 〈x0, x1, x2, . . . ; x xi n = xn+1 for i < n 〉 . Geoghegan and I showed in the early 1980s that Hn(F ) is free abelian of rank 2 for all n ≥ 1. It turns out that the homology admits a natural ring structure, which I calculated a few years later but never published. With the aid of this ring structure one can also calculate the cohomology ring. In this talk, which is dedicated to Ross Geoghegan in honor of his 60th birthday, I will explain where the ring structure comes from and describe the method of calculation.

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