Singularities of Free Group Character Varieties
نویسنده
چکیده
Let Xr be the moduli of SLn, SUn, GLn, or Un valued representations of a rank r free group. We classify the singular stratification of Xr. This comes down to showing that the singular locus corresponds exactly to reducible representations if there exist singularities at all. Additionally, we show that the moduli Xr are generally not topological manifolds, except for a few examples which we explicitly describe.
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