Quantifier Elimination for Valued Fields Equipped with an Automorphism

Abstract

We provide axiomatization and relative quantifier elimination for valued fields equipped with an automorphism, in residue characteristic zero. Similar results are known under strong assumptions on the interaction between the automorphism and the valuation. We remove such assumptions and provide general treatment. As a consequence we obtain an axiomatization of the transseries field (as a valued field with an automorphism) equipped with the automorphism which sends f(x) to f(x+1).