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arXiv · 2602.11343

On the excursion algebra

Dennis Gaitsgory·Kevin Lin·Wyatt Reeves
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Abstract

The excursion algebra associated to a scheme X over a finite field and a reductive group G is the algebra of global functions on the stack of arithmetic G-local systems on X. When X is a curve, this algebra acts on the space of automorphic functions. In this paper we establish some basic properties of this algebra.

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Dennis Gaitsgory, Kevin Lin, Wyatt Reeves. 2026-02-11. On the excursion algebra. https://arxiv.org/abs/2602.11343

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