English

The derived $\infty$-category of Cartier Modules

Algebraic Geometry 2026-02-18 v2 Commutative Algebra

Abstract

For an endofunctor F ⁣:CCF\colon\mathcal{C}\to\mathcal{C} on an (\infty-)category C\mathcal{C} we define the \infty-category Cart(C,F)\operatorname{Cart}(\mathcal{C},F) of generalized Cartier modules as the lax equalizer of FF and the identity. This generalizes the notion of Cartier modules on Fp\mathbb{F}_p-schemes considered in the literature. We show that in favorable cases Cart(C,F)\operatorname{Cart}(\mathcal{C},F) is monadic over C\mathcal{C}. If A\mathcal{A} is a Grothendieck abelian category and F ⁣:AAF\colon\mathcal{A}\to\mathcal{A} is an exact and colimit-preserving endofunctor, we use this fact to construct an equivalence D(Cart(A,F))Cart(D(A),D(F))\mathcal{D}(\operatorname{Cart}(\mathcal{A},F)) \simeq \operatorname{Cart}(\mathcal{D}(\mathcal{A}),\mathcal{D}(F)) of stable \infty-categories. We use this equivalence to construct a perverse t-structure on D(Cart(Mod(X),F))\mathcal{D}(\operatorname{Cart}(\operatorname{Mod}(X), F_*)) for any Noetherian Fp\mathbb{F}_p-scheme XX with absolute Frobenius FF. If FF is finite, this coincides with the perverse t-structure constructed by Baudin.

Keywords

Cite

@article{arxiv.2410.17102,
  title  = {The derived $\infty$-category of Cartier Modules},
  author = {Klaus Mattis and Timo Weiß},
  journal= {arXiv preprint arXiv:2410.17102},
  year   = {2026}
}

Comments

37 pages, final published version

R2 v1 2026-06-28T19:31:39.265Z