Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The mod 2 cohomology rings of congruence subgroups in the Bianchi groups   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{\"o}nnenbeck

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The categories of this paper are: supr-con
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The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
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The categories of this paper are: comp-gas
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The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: econ
12
The categories of this paper are: nucl-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
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The categories of this paper are: funct-an
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The categories of this paper are: hep-lat
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The categories of this paper are: adap-org
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The categories of this paper are: atom-ph