검색 상세

NEWTON POLYGONS, SUCCESSIVE MINIMA, AND DIFFERENT BOUNDS FOR DRINFELD MODULES OF RANK 2

초록/요약

Let K = F-q(T). For a Drinfeld A-module phi of rank 2 defined over C-infinity, there are an associated exponential function e(phi) and lattice Lambda(phi) in C-infinity given by uniformization over C-infinity. We explicitly determine the Newton polygons of e(phi) and the successive minima of Lambda(phi). When phi is defined over K-infinity, we give a refinement of Gardeyn's bounds for the action of wild inertia at infinity on the torsion points of phi and a criterion for the lattice field to be unramified over K-infinity. If phi is in addition defined over K, we make explicit Gardeyn's bounds for the action of wild inertia at finite primes on the torsion points of phi, using results of Rosen, and this gives an explicit bound on the degree of the different divisor of division fields of phi over K.

more