On Thompson's group T and algebraic K-theory

Ross Geoghegan; Marco Varisco

doi:10.1017/9781316771327.005

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arXiv · 1401.0357

On Thompson's group T and algebraic K-theory

Ross Geoghegan·Marco Varisco

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Abstract

Using a theorem of L\"uck-Reich-Rognes-Varisco, we show that the Whitehead group of Thompson's group T is infinitely generated, even when tensored with the rationals. To this end we describe the structure of the centralizers and normalizers of the finite cyclic subgroups of T, via a direct geometric approach based on rotation numbers. This also leads to an explicit computation of the source of the Farrell-Jones assembly map for the rationalized higher algebraic K-theory of the integral group ring of T.

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Ross Geoghegan, Marco Varisco. 2014-01-02. On Thompson's group T and algebraic K-theory. https://doi.org/10.1017/9781316771327.005

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