Published online by Cambridge University Press: 22 January 2016
Let Mn be an n-dimensional Riemannian manifold minimally immersed in the unit sphere Sn+p (1) of dimension n + p. When Mn is compact, Chern, do Carmo and Kobayashi [1] proved that if the square ‖h‖2 of length of the second fundamental form h in Mn is not more than , then either Mn is totally
geodesic, or Mn is the Veronese surface in S4 (1) or Mn is the Clifford torus .
In this paper, we generalize the results due to Chern, do Carmo and Kobayashi [1] to complete Riemannian manifolds.
Partially supported by the SNF, Ges. Nr. 21-27687. 89
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