English

Kashiwara conjugation and the enhanced Riemann-Hilbert correspondence

Algebraic Geometry 2025-03-25 v2 Complex Variables

Abstract

We study some aspects of conjugation and descent in the context of the irregular Riemann-Hilbert correspondence of D'Agnolo-Kashiwara. First, we give a proof of the fact that Kashiwara's conjugation functor for holonomic D-modules is compatible with the enhanced De Rham functor. Afterwards, we work out some complements on Galois descent for enhanced ind-sheaves, slightly generalizing results obtained in previous joint work with Barco, Hien and Sevenheck. Finally, we show how local decompositions of an enhanced ind-sheaf into exponentials descend to lattices over smaller fields. This shows in particular that a structure of the enhanced solutions of a meromorphic connection over a subfield of the complex numbers has implications on its generalized monodromy data (in particular, the Stokes matrices), generalizing and simplifying an argument given in our previous work.

Keywords

Cite

@article{arxiv.2307.15608,
  title  = {Kashiwara conjugation and the enhanced Riemann-Hilbert correspondence},
  author = {Andreas Hohl},
  journal= {arXiv preprint arXiv:2307.15608},
  year   = {2025}
}

Comments

31 pages; v2: minor corrections and improvements of the presentation, final version to appear in Portugaliae Mathematica