Courbes et fibrés vectoriels en théorie de Hodge $z$-adique globale
Siyan Daniel Li-Huerta
TL;DR
The paper constructs a global analogue of the Fargues--Fontaine framework for function fields by introducing the global Hartl--Pink curve and its moduli of $G$-bundles $\mathrm{Bun}_{G,F}$, linking them to the global Kottwitz set $B(F,G)$. It develops a comprehensive program: (i) vector bundles on the global curve via v-descent and a GAGA principle; (ii) a Tannakian description and semistable stratification of $G$-bundles with a localization map to local data; (iii) a fiber-product identity for global shtukas (Theorem D) that mirrors Scholze’s local theory and yields Langlands--Rapoport-type statements for shtuka moduli; (iv) geometric and sheaf-theoretic consequences, including a global conjecture F relating automorphic and spectral sides, and (v) a complete verification of Conjecture F in the commutative (torus) case, with a detailed account of Langlands duality via stacks of Galois representations and IndCoh on LS-stacks. A key technical achievement is a GAGA-type comparison over sousperfectoid spaces, enabling a robust bridge between algebraic and analytic worlds in this global setting.
Abstract
We study the global analogue of the Fargues-Fontaine curve over function fields $F$. We prove some foundational results about its moduli of $G$-bundles $\operatorname{Bun}_{G,F}$, which is a geometrization of the global Kottwitz set $B(F,G)$. For example, $\operatorname{Bun}_{G,F}$ plays the role of Igusa stacks over function fields. We use $\operatorname{Bun}_{G,F}$ to reformulate the global Langlands conjecture for $G$ over $F$ in terms of categorical local Langlands, refining conjectures of Arinkin-Gaitsgory-Kazhdan-Raskin-Rozenblyum-Varshavsky and Zhu. Finally, we verify this conjecture when $G$ is commutative. Along the way, we prove a GAGA theorem for smooth proper schemes over sousperfectoid spaces, which is of independent interest.
