Geometrie non-commutative, formule des traces et conducteur de Bloch

This text is based on a talk by the first named author at the first congress of the SMF (Tours, 2016). We present Blochs conductor formula, which is a conjectural formula describing the change of topology in a family of algebraic varieties when the parameter specialises to a critical value. The main objective of this paper is to describe a general approach to the resolution of Blochs conjecture based on techniques from both non-commutative geometry and derived geometry.