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arXiv · 2511.12765

Transfers and Unstable Degrees in the $\mathbb{A}^{1}$-Brouwer Degrees Package for Macaulay2

Stephanie Atherton·Somak Dutta·Jordy Lopez Garcia·Joel Louwsma·Yuyuan Luo·Wern Juin Gabriel Ong·Ruzho Sagarayaj
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Abstract

We describe a significant update to the Macaulay2 package A1BrouwerDegrees. We extend several methods in the previous version of the package to the setting of finite étale algebras, allowing the computation of transfers along finite étale extensions. Additionally, we implement a number of new features for the computation of unstable $\mathbb{A}^{1}$-Brouwer degrees and manipulation of classes in the unstable Grothendieck--Witt group.

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Stephanie Atherton, Somak Dutta, Jordy Lopez Garcia, Joel Louwsma, Yuyuan Luo, Wern Juin Gabriel Ong, Ruzho Sagarayaj. 2025-11-16. Transfers and Unstable Degrees in the $\mathbb{A}^{1}$-Brouwer Degrees Package for Macaulay2. https://arxiv.org/abs/2511.12765

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