Small Height and Infinite Non-Abelian Extensions

Philipp Habegger

Published 2011-09-27, updated 2013-01-29Version 2

Let $E$ be an elliptic curve defined over the rationals without complex multiplication. The field $F$ generated by all torsion points of $E$ is an infinite, non-abelian Galois extension of the rationals which has unbounded, wild ramification above all primes. We prove that the absolute logarithmic Weil height of an element of $F$ is either zero or bounded from below by a positive constant depending only on $E$. We also show that the N\'eron-Tate height has a similar gap on $E(F)$ and use this to determine the structure of the group $E(F)$.