K3 surfaces with Picard number one and infinitely many rational points
Abstract
Description
In general, not much is known about the arithmetic of K3 surfaces. Once the geometric Picard number, which is the rank of the Neron-Severi group over an algebraic closure of the base field, is high enough, more structure is known and more can be said. However, until recently not a single K3 surface was known to have geometric Picard number one. We give explicit examples of such surfaces over the rational numbers. This solves an old problem that has been attributed to Mumford. The examples we give also contain infinitely many rational points, thereby answering a question of Swinnerton-Dyer and Poonen.
10 pages, LaTeX, submitted to Compositio Mathematica; Part of the main theorem was false in the first version and is now fixed by leaving out the real analytic topology
10 pages, LaTeX, submitted to Compositio Mathematica; Part of the main theorem was false in the first version and is now fixed by leaving out the real analytic topology