A Kirwan-ness Stratification for Loop Groups
نویسنده
چکیده
We study a stratification of Kirwan-Ness type for the action of the loop group on the moduli space of framed bundles on a surface cut along a circle. The genus zero case is equivalent to Birkhoff decomposition of the loop group. The stratification is used to prove versions of Kähler quantization commutes with reduction and Kirwan surjectivity.
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