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Unpublished Paper
Torsion In The Cohomology Of Congruence Subgroups Of SL (4. Z) And Galois Representations
Journal of Algebra (2010)
  • Avner Ash
  • Paul E. Gunnells, University of Massachusetts - Amherst
  • Mark McConnell
Abstract
We report on the computation of torsion in certain homology theories of congruence subgroups of SL(4,Z). Among these are the usual group cohomology, the Tate–Farrell cohomology, and the homology of the sharbly complex. All of these theories yield Hecke modules. We conjecture that the Hecke eigenclasses in these theories have attached Galois representations. The interpretation of our computations at the torsion primes 2, 3, 5 is explained. We provide evidence for our conjecture in the 15 cases of odd torsion that we found in levels ⩽31.
Keywords
  • Automorphic forms,
  • Cohomology of arithmetic groups,
  • Hecke operators,
  • Galois representations,
  • Torsion cohomology classes
Disciplines
Publication Date
August 10, 2010
Comments
Pre-published version downloaded from archive ArXiv.org. Published version located at http://www.sciencedirect.com/science/article/pii/S0021869310003315#.
Citation Information
Avner Ash, Paul E. Gunnells and Mark McConnell. "Torsion In The Cohomology Of Congruence Subgroups Of SL (4. Z) And Galois Representations" Journal of Algebra (2010)
Available at: http://works.bepress.com/paul_gunnells/40/