An Isaac Newton Institute Programme

Model Theory and Applications to Algebra and Analysis

Approximation in Difference Valuation Rings

2nd March 2005

Author: Luc Belair (UQAM)

Abstract

I will discuss a result analogous to a theorem of Greenberg on an approximation property in henselian discrete valuation rings, but for polynomial equations involving also a fixed automorphism. In the case of Witt vectors and their Frobenius, a nullstellensatz for these equations can be deduced.