The homotopy-invariance of constructible sheaves
Abstract
The purpose of this paper is to explain why the functor that sends a stratified topological space to the -category of constructible (hyper)sheaves on with coefficients in a large class of presentable categories is homotopy-invariant. To do this, we first establish a number of results in the unstratified setting, i.e., the setting of locally constant (hyper)sheaves. For example, if is a locally weakly contractible topological space and is a presentable -category, then we give a concrete formula for the constant hypersheaf functor . This formula lets us show that the constant hypersheaf functor is a right adjoint, and is fully faithful if is also weakly contractible. It also lets us prove a general monodromy equivalence and categorical K\"unneth formula for locally constant hypersheaves.
Keywords
Cite
@article{arxiv.2010.06473,
title = {The homotopy-invariance of constructible sheaves},
author = {Peter J. Haine and Mauro Porta and Jean-Baptiste Teyssier},
journal= {arXiv preprint arXiv:2010.06473},
year = {2022}
}
Comments
28 pages. Comments very welcome! v5. Clarified a few things and added some remarks. A slightly shorter version of this paper will appear in Homology, Homotopy and Applications. v4. Completely revised. Two new authors. Much stronger results. v3. Fixed the definition of a "constructible hypersheaf" and clarified a few points. v2. Fixed some typos