SIGMA 22 (2026), 088, 18 pages      arXiv:2512.18380      https://doi.org/10.3842/SIGMA.2026.088

Finite Group Actions on Quasi-Hamiltonian Spaces

Keito Takegoshi
Department of Mathematics, Faculty of Science Division I, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan

Received December 26, 2025, in final form August 28, 2026; Published online September 18, 2026

Abstract
We organize fundamental properties of quasi-Hamiltonian spaces on which a finite group acts, and we apply them to the theory of moduli spaces of flat connections on an oriented compact surface with boundary.

Key words: quasi-Hamiltonian geometry; moduli space of flat connections.

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