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arXiv · 1302.4537

E_1-degeneration of the irregular Hodge filtration (with an appendix by Morihiko Saito)

Hélène Esnault·Claude Sabbah·Jeng-Daw Yu
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Abstract

For a regular function f on a smooth complex quasi-projective variety, J.-D. Yu introduced in arXiv:1203.2338 a filtration (the irregular Hodge filtration) on the de Rham complex with twisted differential d+df, extending a definition of Deligne in the case of curves. In this article, we show the degeneration at E_1 of the spectral sequence attached to the irregular Hodge filtration, by using the method of arXiv:0804.4328. We also make explicit the relation with a complex introduced by M. Kontsevich and give details on its proof of the corresponding E_1 degeneration, by reduction to characteristic p, when the pole divisor of the function is reduced with normal crossings. In Appendix E, M. Saito gives a different proof of the latter statement with a possibly non reduced normal crossing pole divisor.

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Hélène Esnault, Claude Sabbah, Jeng-Daw Yu. 2013-02-19. E_1-degeneration of the irregular Hodge filtration (with an appendix by Morihiko Saito). https://doi.org/10.1515/crelle-2014-0118

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