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arXiv · 1506.03912

On the equivariant K-homology of PSL\_2 of the imaginary quadratic integers

Alexander Rahm
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Abstract

We establish formulae for the part due to torsion of the equivariant K-homology of all the Bianchi groups (PSL\_2 of the imaginary quadratic integers), in terms of elementary number-theoretic quantities. To achieve this, we introduce a novel technique in the computation of Bredon homology: representation ring splitting, which allows us to adapt the recent technique of torsion subcomplex reduction from group homology to Bredon homology.

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Alexander Rahm. 2016-01-21. On the equivariant K-homology of PSL\_2 of the imaginary quadratic integers. https://arxiv.org/abs/1506.03912

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