## Algebraic & Geometric Topology

### Fundamental groups of topological stacks with the slice property

Behrang Noohi

#### Abstract

The main result of the paper is a formula for the fundamental group of the coarse moduli space of a topological stack. As an application, we find simple formulas for the fundamental group of the coarse quotient of a group action on a topological space in terms of the fixed point data. In particular, we recover, and vastly generalize, results of Armstrong, Bass, Higgins and Taylor and Rhodes.

#### Article information

Source
Algebr. Geom. Topol., Volume 8, Number 3 (2008), 1333-1370.

Dates
Revised: 14 June 2008
Accepted: 15 June 2008
First available in Project Euclid: 20 December 2017

https://projecteuclid.org/euclid.agt/1513796889

Digital Object Identifier
doi:10.2140/agt.2008.8.1333

Mathematical Reviews number (MathSciNet)
MR2443246

Zentralblatt MATH identifier
1149.22003

#### Citation

Noohi, Behrang. Fundamental groups of topological stacks with the slice property. Algebr. Geom. Topol. 8 (2008), no. 3, 1333--1370. doi:10.2140/agt.2008.8.1333. https://projecteuclid.org/euclid.agt/1513796889

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