1 Group Action on Instanton Bundles over P 3 1
نویسنده
چکیده
Abstract: Denote by MI(k) the moduli space of k-instanton bundles E of rank 2 on P = P(V ) and by Zk(E) the scheme of k-jumping lines. We prove that [E] ∈ MI(k) is not stable for the action of SL(V ) if Zk(E) 6= ∅. Moreover dimSym(E) ≥ 1 if lengthZk(E) ≥ 2. We prove also that E is special if and only if Zk(E) is a smooth conic. The action of SL(V ) on the moduli of special instanton bundles is studied in detail.
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