In this paper we prove that minimal 3-spheres of CR type with constant sectional curvature c in the complex projective space CP" are all equivariant and therefore the immersion is rigid. The curvature c of the sphere should be c = \/{m 2 -1) for some integer m > 2, and the full dimension is n = 2m 2 -3. An explicit analytic expression for such an immersion is given.2000 Mathematics subject classification: primary 53C42; secondary 53C55. Keywords and phrases: minimal, constant curvature, CR-submanifold, complex projective space.
PreliminaryIn In this paper, we assume that N is the complex projective space CP" with constant holomorphic sectional curvature 4.The minimal surface theory in CP" has made a great progress over the past thirty years. For constant curved minimal 2-spheres in CP", the immersion CP" by using arithmetical procedure [2].Up to now merely a few examples have been known for higher dimensional minimal submanifolds in CP". There are some examples of holomorphic submanifolds and Lagrangian minimal submanifolds [3,4,6]. In [5] we studied equivariant minimal 3-spheres with constant (sectional) curvature c immersed in CP". Here the terminology Project supported by the NSFC (10261006), the NSFJP (0211005) and the FANEDD (200217).