HYPERGEOMETRIC SERIES AND ARITHMETIC–GEOMETRIC MEAN OVER 2-ADIC FIELDS

Abstract

Dwork proved that the Gaussian hypergeometric function on p-adic numbers can be extended to a function which takes values of the unit roots of ordinary elliptic curves over a finite field of characteristic p ≥ 3. We present an analogous theory in the case p = 2. As an application, we give a relation between the canonical lift and the unit root of an elliptic curve over a finite field of characteristic 2 by using the 2-adic arithmetic–geometric mean.