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arXiv · 0710.3327

A la Fock-Goncharov coordinates for PU(2,1)

Julien Marche·Pierre Will
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Abstract

We describe a set of coordinates on the PU(2,1)-representation variety of the fundamental group of an oriented punctured surface $S$ with negative Euler characteristic. The main technical tool we use is a set of geometric invariants of a triple of flags in the complex hyperpolic plane. We establish a bijection between a set of decorations of an ideal triangulation of $S$ and a subset of the PU(2,1)-representation variety of $π_1(S)$.

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Julien Marche, Pierre Will. 2007-10-17. A la Fock-Goncharov coordinates for PU(2,1). https://arxiv.org/abs/0710.3327

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