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arXiv · 1704.04832

Characteristic cycles and the conductor of direct image

Takeshi Saito
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Abstract

We prove the functoriality for proper push-forward of the characteristic cycles of constructible complexes by morphisms of smooth projective schemes over a perfect field, under the assumption that the direct image of the singular support has the dimension at most that of the target of the morphism. The functoriality is deduced from a conductor formula which is a special case for morphisms to curves. The conductor formula in the constant coefficient case gives the geometric case of a formula conjectured by Bloch.

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Takeshi Saito. 2017-04-16. Characteristic cycles and the conductor of direct image. https://doi.org/10.1090/jams/959

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