A ug 2 00 9 ON NORI ’ S OBSTRUCTION TO UNIVERSAL BUNDLES
نویسنده
چکیده
Let G be SLn, Sp2n or SOn. We consider the moduli space M of semistable principal G-bundles over a curve X . Our main result is that if U is a Zariski open subset of M then there is no universal bundle on U × X .
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