2019/07/30 by Kazuki Hiroe, Hiroe, Kazuki
Mathematics · #Advanced Algebra and Geometry #Algebraic Geometry (math.AG) #Algebraic Geometry and Number Theory #FOS: Mathematics #Geometric and Algebraic Topology #math.AG
paper · pdf · doi:10.48550/arxiv.1907.12846
22 pages. To appear in J. Geom. Phys
openalex publication_date 2019/07/30 · arxiv created 2020/12/09 · arxiv updated 2020/12/10 · openalex created_date 2020/12/21 · openalex updated_date 2026/07/28
We show a coincidence of index of rigidity of differential equations with irregular singularities on a compact Riemann surface and Euler characteristic of the associated spectral curves which are recently called irregular spectral curves. Also we present a comparison of local invariants, so called Milnor formula which links the Komatsu-Malgrange irregularity of differential equations and Milnor number of the spectral curves.