On the splitting principle for cohomological invariants of reflection\n groups

2019/08/21 by Stefan Gille, Christian Hirsch, Gille, Stefan +1
Mathematics · #19D45 #Algebraic Geometry (math.AG) #Algebraic Geometry and Number Theory #Algebraic structures and combinatorial models #FOS: Mathematics #Homotopy and Cohomology in Algebraic Topology

paper · pdf · doi:10.48550/arxiv.1908.08146

openalex publication_date 2019/08/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

Let \k₀ be a field and W a finite orthogonal reflection group\nover \k₀. We prove Serre's splitting principle for cohomological\ninvariants of W with values in Rost's cycle modules (over \k₀)\nif the characteristic of \k₀ is coprime to |W|. We then show\nthat this principle for such groups holds also for Witt- and Milnor-Witt\nK-theory invariants.\n

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