Homology, Homotopy and Applications

Higher monodromy

Pietro Polesello and Ingo Waschkies

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For a given category $\mathsf{C}$ and a topological space $X$, the constant stack on $X$ with stalk $\mathsf{C}$ is the stack of locally constant sheaves with values in $\mathsf{C}$. Its global objects are classified by their monodromy, a functor from the fundamental groupoid $\Pi_1(X)$ to $\mathsf{C}$. In this paper we recall these notions from the point of view of higher category theory and then define the 2-monodromy of a locally constant stack with values in a 2-category $\mathsf{C}$ as a 2-functor from the homotopy 2-groupoid $\Pi_2(X)$ to $\mathsf{C}$. We show that 2-monodromy classifies locally constant stacks on a reasonably well-behaved space $X$. As an application, we show how to recover from this classification the cohomological version of a classical theorem of Hopf, and we extend it to the non abelian case.

Article information

Homology Homotopy Appl., Volume 7, Number 1 (2005), 109-150.

First available in Project Euclid: 13 February 2006

Permanent link to this document

Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 18G50: Nonabelian homological algebra
Secondary: 55P99: None of the above, but in this section


Polesello, Pietro; Waschkies, Ingo. Higher monodromy. Homology Homotopy Appl. 7 (2005), no. 1, 109--150. https://projecteuclid.org/euclid.hha/1139839509

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