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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 \'{e}tale algebras, allowing the computation of transfers along finite \'{e}tale 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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