Semiorthogonal decompositions for stacks

Chenjing Bu; Tudor Pădurariu; Yukinobu Toda

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arXiv · 2605.25976

Semiorthogonal decompositions for stacks

Chenjing Bu·Tudor Pădurariu·Yukinobu Toda

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Abstract

We give a systematic construction of semiorthogonal decompositions of derived categories of coherent sheaves on quasi-smooth derived algebraic stacks over $\mathbb{C}$, where the summands are subcategories defined by weight conditions, and the inclusion functors are given by parabolic induction. The summands are indexed by the component lattice of the stack, a central combinatorial structure in intrinsic Donaldson-Thomas theory. As examples, we obtain semiorthogonal decompositions for moduli stacks of semistable $G$-bundles or $G$-Higgs bundles on a curve, and moduli stacks of de Rham or Betti $G$-local systems on a curve, for reductive groups $G$ not necessarily of type A.

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BibTeX RIS

Chenjing Bu, Tudor Pădurariu, Yukinobu Toda. 2026-05-25. Semiorthogonal decompositions for stacks. https://arxiv.org/abs/2605.25976

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