4 papers
Bounding ramification with coherent sheaves
Haoyu Hu, Jean-Baptiste Teyssier
Given a coherent sheaf E on a scheme of finite type X over a perfect field, we introduce a category of complexes of étale sheaves on X with logarithmic conductors bounded by E and…
Characteristic cycle and wild Lefschetz theorems
Haoyu Hu, Jean-Baptiste Teyssier
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…
Semi-continuity for conductor divisors of étale sheaves
Haoyu Hu, Jean-Baptiste Teyssier
In this article, we prove a semi-continuity property for both conductor divisors and logarithmic conductor divisors for étale sheaves on higher relative dimensions in a geometric…
Estimates for Betti numbers and relative Hermite-Minkowski theorem for perverse sheaves
Haoyu Hu, Jean-Baptiste Teyssier
We prove estimates for the Betti numbers of constructible sheaves in characteristic p>0 depending only on their rank, stratification and wild ramification. In particular, given a s…