Relations between Dieudonné displays and crystalline Dieudonné theory

Abstract

We discuss the relation between crystalline Dieudonné theory and Dieudonné displays of $p$-divisible groups. The theory of Dieudonné displays is extended to the prime 2 without restriction, which implies that the classification of finite locally free group schemes by Breuil–Kisin modules holds for the prime 2 as well.