220920 Dobben de Bruyn

September 20, 2022

Title: Étale cohomology and independence of ℓ (MI-talk)

Speaker: Remy Dobben de Bruyn

The geometric complexity of a complex algebraic variety is measured by algebraic invariants like the fundamental group and (co)homology groups. I will explain why algebraic geometers believed that such invariants should also exist for varieties over finite fields, and sketch how this was realised in the 1960s by ℓ-adic étale cohomology (depending on an auxiliary prime number ℓ). At the end of the talk, I will discuss some results and work in progress on the foundational "independence of ℓ" problem.

Bookmark the permalink.

Comments are closed