RéGA

The Bass-Quillen conjecture and affine representability for vector bundles

par Daniel Marlowe (University of Warwick)

Europe/Paris
Salle Pierre Grisvard (Institut Henri Poincaré)

Salle Pierre Grisvard

Institut Henri Poincaré

Description
The Morel-Voevodsky A1-homotopy category is a prime setting in which to approach questions in geometry by means of topological techniques. A notable example of this is the importation of obstruction theory into the study of vector bundles over algebraic varieties; this allows one to reduce statements about such vector bundles to cohomological criteria, and in doing so demonstrates that the heart of the matter is often a computation of a K-theoretic nature.
 
In this expository talk, we will review some elements of this motivic obstruction theory, and in particular the key geometric ingredient in the form of Lindel-Popescu's solution to the Bass-Quillen conjecture. We will then sketch its role in the proof of affine representability for vector bundles in the A1-homotopy category.