Automorphic congruences between torsion cohomological classes
Number Theory
2025-10-03 v3
Abstract
For two representations of some local division algebra, congruent modulo , giving rise to two Harris-Taylor local systems on the corresponding Newton strata of the special fiber of a KHT Shimura varieties, we prove that the -torsion of each of their cohomology groups with compact supports are isomorphic, or equivalently the free quotients of each of the cohomology groups are congruent modulo . We then deduce the construction of accurate non tempered automorphic congruences for a similitude group with signature .
Cite
@article{arxiv.2201.06048,
title = {Automorphic congruences between torsion cohomological classes},
author = {Boyer Pascal},
journal= {arXiv preprint arXiv:2201.06048},
year = {2025}
}
Comments
correction of some typos