Functoriality of Moduli Spaces of Global $\mathbb G$-Shtukas

Abstract

Moduli spaces of global $\mathbb G$-shtukas play a crucial role in the Langlands program for function fields. We analyze their functoriality properties following a change of the curve and a change of the group scheme $\mathbb G$ under various aspects. In particular, we prove two finiteness results which are of interest in the study of stratifications of these moduli spaces and which potentially allow the formulation of an analog of the Andr\'{e}-Oort conjecture for global $\mathbb G$-shtukas.