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arXiv · 1406.6083

On the auto Igusa-zeta function of an Algebraic Curve

Abstract

We study endomorphisms of complete Noetherian local rings in the context of motivic integration. Using the notion of an auto-arc space, we introduce the (reduced) auto-Igusa zeta series at a point, which appears to measure the degree to which a variety is not smooth that point. We conjecture a closed formula in the case of curves with one singular point, and we provide explicit formulas for this series in the case of the cusp and the node. Using the work of Denef and Loeser, one can show that this series will often be rational. These ideas were obtained through extensive calculations in Sage. Thus, we include a Sage script which was used in these calculations. It computes the affine arc spaces $\nabla_{\mathfrak{n}}X$ provided that $X$ is affine, $\mathfrak{n}$ is a fat point, and the ground field is of characteristic zero. Finally, we show that the auto Poincar\'e series will often be rational as well and connect this to questions concerning new types of motivic integrals.

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Andrew Stout. 2014-06-23. On the auto Igusa-zeta function of an Algebraic Curve. https://arxiv.org/abs/1406.6083

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