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arXiv · 2606.26070

Polynomiality of the Generalized Verschiebung Degree

Siqing Zhang
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Abstract

For a general curve in positive characteristic, taking the Frobenius pullback induces a generically finite rational map V on the moduli space of rank 2 vector bundles with trivial determinant. Recently, Kondo--Wakabayashi show that the generic degree of V, considered as a function on the characteristic of the base field, is a quasi-polynomial. In this paper, we show that this quasi-polynomial is indeed a polynomial, and we write out this polynomial explicitly.

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Siqing Zhang. 2026-06-24. Polynomiality of the Generalized Verschiebung Degree. https://arxiv.org/abs/2606.26070

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