On $$W_2$$ W 2 -lifting of Frobenius of algebraic surfaces

Abstract

The classification of minimal algebraic surfaces in positive characteristics was accomplished by Bombieri and Mumford in the 1970s. In this work we decide completely which minimal algebraic surfaces in positive characteristics allow a lifting of their Frobenius over the truncated Witt rings of length 2. Besides, we show that the Frobenius morphism of many projective rational surfaces cannot be lifted to \(W_2(k)\).