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arXiv · 1712.09234

Characteristic cycle of a rank one sheaf and ramification theory

Yuri Yatagawa
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Abstract

We compute the characteristic cycle of a rank one sheaf on a smooth surface over a perfect field of positive characteristic. We construct a canonical lifting on the cotangent bundle of Kato's logarithmic characteristic cycle using ramification theory and prove the equality of the characteristic cycle and the canonical lifting. As corollaries, we obtain a computation of the singular support in terms of ramification theory.

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Yuri Yatagawa. 2017-12-26. Characteristic cycle of a rank one sheaf and ramification theory. https://arxiv.org/abs/1712.09234

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