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arXiv · 1807.06930

On the relative twist formula of $\ell$-adic sheaves

Enlin Yang·Yigeng Zhao
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Abstract

We propose a conjecture on the relative twist formula of $\ell$-adic sheaves, which can be viewed as a generalization of Kato-Saito's conjecture. We verify this conjecture under some transversal assumptions. We also define a relative cohomological characteristic class and prove that its formation is compatible with proper push-forward. A conjectural relation is also given between the relative twist formula and the relative cohomological characteristic class.

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Enlin Yang, Yigeng Zhao. 2018-07-18. On the relative twist formula of $\ell$-adic sheaves. https://arxiv.org/abs/1807.06930

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