English

$\mathrm{D}-\mathrm{mod}(\mathrm{Bun}_G^\mathrm{I})$ is Compactly Generated

Algebraic Geometry 2024-12-03 v2

Abstract

Drinfeld and Gaitsgory proved that Dmod(BunG)\mathrm{D}-\mathrm{mod}(\mathrm{Bun}_G) is compactly generated. Let BunGI\mathrm{Bun}_G^{\mathrm{I}} be the algebraic stack of principal GG-bundles on XX together with Iwahori level structure at a fixed point xXx \in X. More generally, for a finite collection of points x1,...,xkXx_1, ..., x_k \in X, let BunG(I;x1,...,xk)\mathrm{Bun}_G^{(\mathrm{I}; x_1, ..., x_k)} be the algebraic stack of principal GG-bundles on XX together with Iwahori level structure at each point xjx_j. We will show that Dmod(BunGI)\mathrm{D}-\mathrm{mod}(\mathrm{Bun}_G^{\mathrm{I}}) and Dmod(BunG(I;x1,...,xk))\mathrm{D}-\mathrm{mod}(\mathrm{Bun}_G^{(\mathrm{I}; x_1, ..., x_k)}) are compactly generated.

Cite

@article{arxiv.2411.03057,
  title  = {$\mathrm{D}-\mathrm{mod}(\mathrm{Bun}_G^\mathrm{I})$ is Compactly Generated},
  author = {Taeuk Nam},
  journal= {arXiv preprint arXiv:2411.03057},
  year   = {2024}
}

Comments

30 pages, fixed minor typos

R2 v1 2026-06-28T19:48:51.817Z