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arXiv · 1912.04788

The trace of the local $\mathbf{A}^1$-degree

Abstract

We prove that the local $\mathbb{A}^1$-degree of a polynomial function at an isolated zero with finite separable residue field is given by the trace of the local $\mathbb{A}^1$-degree over the residue field. This fact was originally suggested by Morel's work on motivic transfers and by Kass and Wickelgren's work on the Scheja-Storch bilinear form. As a corollary, we generalize a result of Kass and Wickelgren's relating the Scheja-Storch form and the local $\mathbb{A}^1$-degree.

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Thomas Brazelton, Robert Burklund, Stephen McKean, Michael Montoro, Morgan Opie. 2019-12-10. The trace of the local $\mathbf{A}^1$-degree. https://doi.org/10.4310/hha.2021.v23.n1.a13

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