Characteristic cycle and wild Lefschetz theorems
Algebraic Geometry
2025-06-17 v2 Number Theory
Abstract
By relying on a new approach to Lefschetz type questions based on Beilinson's singular support and Saito's characteristic cycle, we prove an instance of the wild Lefschetz theorem envisioned by Deligne. Our main tool are new finiteness results for the characteristic cycles of perverse sheaves.
Cite
@article{arxiv.2502.11064,
title = {Characteristic cycle and wild Lefschetz theorems},
author = {Haoyu Hu and Jean-Baptiste Teyssier},
journal= {arXiv preprint arXiv:2502.11064},
year = {2025}
}
Comments
Hyperplane case written in a separate section from the higher codimension case. Wild Lefschetz restricted to finite coefficients due to an inaccuracy in [ES21]. See https://page.mi.fu-berlin.de/esnault/preprints/helene/138b_small_erratum.pdf for a correction. Comments are welcome