On reductions of Selmer sections

Wojciech Porowski

公開日: 2025/9/19

Abstract

We consider reductions of Selmer sections of the \'etale homotopy sequence of a hyperbolic curve over a number field. We show that the conjugacy class of a noncuspidal Selmer section is uniquely determined by its reduction on a set of density one. Moreover, we show that a noncuspidal Selmer section reduces to cusps only on a set of density zero, at least after a finite field extension.