Mathematische Zeitschrift Extrinsic Killing spinors
نویسندگان
چکیده
Under intrinsic and extrinsic curvature assumptions on a Riemannian spin manifold and its boundary, we show that there is an isomorphism between the restriction to the boundary of parallel spinors and extrinsic Killing spinors of nonnegative Killing constant. As a corollary, we prove that a complete Ricci-flat spin manifold with mean-convex boundary isometric to a round sphere, is necessarily a flat disc. Mathematics Subject Classification (1991): 53C27, 53C40, 53C80, 58G25
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