English

Mukai Duality for abelian stacks

Algebraic Geometry 2023-11-21 v1 K-Theory and Homology Number Theory

Abstract

An abelian stack is a stacky generalization of an abelian variety that was introduced by Brochard. Just as an abelian variety has a dual, an abelian stack A\mathcal{A} has a dual D(A)\mathfrak{D}(\mathcal{A}) which generalizes the classical dual. In general, D(A)\mathfrak{D}(\mathcal{A}) is no longer an abelian stack but a commutative group scheme which is an extension of a finite, flat, and finitely presented commutative group scheme by an abelian scheme. We show that Fourier-Mukai duality holds for tame abelian stacks and their duals. Our approach is as follows. Let QC(A)QC_\infty(\mathcal{A}) be the stable infinity category of quasi-coherent sheaves on A\mathcal{A}. We define a Poincare bundle on A×D(A)\mathcal{A}\times \mathfrak{D}(\mathcal{A}) and use this to show that QC(A)QC_\infty(\mathcal{A}) and QC(D(A))QC_\infty(\mathfrak{D}(\mathcal{A})) are dual as objects in the infinity category of stable infinity categories. By a result of Ben-Zvi,Francis and Nadler we have that QC(A)QC_\infty(\mathcal{A}) is self dual, giving that QC(A)QC(D(A))QC_\infty(\mathcal{A})\cong QC_\infty(\mathfrak{D}(\mathcal{A})) which gives the statement for the derived categories. In addition we give new examples of tame abelian stacks.

Keywords

Cite

@article{arxiv.2311.11492,
  title  = {Mukai Duality for abelian stacks},
  author = {Ajneet Dhillon and Brett Nasserden},
  journal= {arXiv preprint arXiv:2311.11492},
  year   = {2023}
}
R2 v1 2026-06-28T13:25:38.073Z