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arXiv · 2607.22918

K-theory of Weighted Blowups

Veronica Arena·Alessio Cela·Alberto Landi·Michele Pernice
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Abstract

We compute the K-theory of weighted blowups of smooth stacks satisfying the resolution property along smooth centers. As an application, we determine the K-theory of the stack of stable genus 1 curves with 2 marked points. Furthermore, we express the Lambda polynomial of the tangent complex of the blowup morphism in terms of the blowup data. Along the way, we generalize the Anderson-Payne construction of equivariant operational K-theory from torus actions to actions of smooth affine algebraic groups.

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Veronica Arena, Alessio Cela, Alberto Landi, Michele Pernice. 2026-07-24. K-theory of Weighted Blowups. https://arxiv.org/abs/2607.22918

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