Nicolas Bergeron: Torsion in the homology of locally symmetric spaces
From CRCG-Wiki
Homology groups are Z-modules with a free part and a torsion part. Avner Ash and others have conjectured that the torsion part of the homology of arithmetic locally symmetric spaces should fit into the framework of the Langlands program. This can be made sufficilently explicit to predict when arithmetic locally symmetric manifolds should have "a lot" of torsion in their homology. I will try to explain what "a lot" means, state a precise conjecture and sketch the proof a particular case of it.
All this is joint work with Akshay Venkatesh.
