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arXiv · 1707.06078

The mod 2 cohomology rings of congruence subgroups in the Bianchi groups

Ethan Berkove·Grant Lakeland·Alexander Rahm·Anh Tuan Bui·Sebastian Schönnenbeck
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Abstract

We provide new tools for the calculation of the torsion in the cohomology of congruence subgroups in the Bianchi groups : An algorithm for finding particularly useful fundamental domains, and an analysis of the equivariant spectral sequence combined with torsion subcomplex reduction.\_\_\_\_\_\_\_\_\_\_With an appendix by Bui Anh Tuan and Sebastian Sch{ö}nnenbeck

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Ethan Berkove, Grant Lakeland, Alexander Rahm, Anh Tuan Bui, Sebastian Schönnenbeck. 2019-10-16. The mod 2 cohomology rings of congruence subgroups in the Bianchi groups. https://arxiv.org/abs/1707.06078

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