Deciding almost freeness of an action is NP-hard

2015/08/18 by Manuel Amann, Amann, Manuel
Mathematics · #55P62 (Secondary) #68Q17 (Primary) #Advanced Topology and Set Theory #Algebraic Topology (math.AT) #FOS: Mathematics #Geometric and Algebraic Topology #Homotopy and Cohomology in Algebraic Topology

paper · pdf · doi:10.48550/arxiv.1508.04385

openalex publication_date 2015/08/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We encode a compact Lie group action on a compact manifold by the Sullivan model of its Borel construction. We then prove that deciding whether this action is almost free is NP-hard.

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