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arXiv · 2607.05575

Virtual Jeffrey--Kirwan localisation

Riccardo Ontani·Richard P. Thomas
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Abstract

We express integrals over virtual cycles of GIT quotients $X/\!\!/G$ in terms of integrals over virtual cycles of fixed loci $X^T$. The results hold for both perfect obstruction theories and $(-2)$-shifted symplectic structures, in cohomology and in $K$-theory, and for noncompact Deligne-Mumford stacks acted on by a reductive group with compact quotient.

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Riccardo Ontani, Richard P. Thomas. 2026-07-06. Virtual Jeffrey--Kirwan localisation. https://arxiv.org/abs/2607.05575

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