Second Variation of Superminimal Surfaces into Self-dual Einstein Four-manifolds
نویسندگان
چکیده
The index of a compact orientable superminimal surface of a selfdual Einstein four-manifold M with positive scalar curvature is computed in terms of its genus and area. Also a lower bound of its nullity is obtained. Applications to the cases M = S4 and M = CP2 are given, characterizing the standard Veronese immersions and their twistor deformations as those with lowest index.
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تاریخ انتشار 1997