A vanishing theorem for quadratic intersection multiplicities

Niels Feld

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arXiv · 2112.05200

A vanishing theorem for quadratic intersection multiplicities

Niels Feld

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Abstract

We study intersection theoretic problems in the setting of Chow-Witt groups with coefficients in a fixed Milnor-Witt cycle algebra over a perfect field. We prove that the product maps on such groups satisfy the following property: given two points in a regular local scheme with supports which do not intersect properly, their product vanishes. This gives an analogue of Serre's vanishing result for intersection multiplicities.

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Niels Feld. 2021-12-09. A vanishing theorem for quadratic intersection multiplicities. https://arxiv.org/abs/2112.05200

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