研究欧氏空间Rn+1(n≥3)中完备超曲面M上的L2调和2-形式.应用Bochner技巧,证明了当M的无迹对称张量Φ和平均曲率向量H的Ln(M)范数均有只依赖于n的适当上界时,M上的L2调和2-形式是平行的.进一步,若M为非极小超曲面,则M上不存在非平凡的L2调和2-形式.
In this paper, we study L2 harmonic 2-forms on a complete hypersurface M of Euclidean space Rn+1(n ≥ 3). By applying the Bochner technique, we prove that if the Ln(M) norms of the traceless second fundamental form Φ and the mean curvature vector H are both bounded from above by certain constants which depend only on n, then the L2 harmonic 2-forms on M are parallel. Furthermore, if M is a non-minimal hypersurface, then there is no nontrivial L2 harmonic 2-form on M.
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