Niels Lauritzen

Lifts of endomorphisms of Weyl algebras modulo p2

Let φ denote a k -algebra endomorphism of the n -th Weyl algebra A n ( k ) over a perfect field k of positive characteristic p . We prove that φ can be lifted to an endomorphism of the Weyl algebra A n ( W 2 ( k ) ) over the Witt vectors W 2 ( k ) of length two over k if and only...