# SEMI-INVARIANT SUBMANIFOLDS OF CODIMENSION 3 OF A COMPLEX PROJECTIVE SPACE IN TERMS OF THE JACOBI OPERATOR

• HER, JONG-IM (Department of Mathematics, Chosun University) ;
• KI, U-HANG (Department of Mathematics, Kyungpook National University) ;
• LEE, SEONG-BAEK (Department of Mathematics, Chosun University)
• Published : 2005.02.01

#### Abstract

In this paper, we characterize some semi-invariant sub-manifolds of codimension 3 with almost contact metric structure ($\phi$, $\xi$, g) in a complex projective space $CP^{n+1}$ in terms of the structure tensor $\phi$, the Ricci tensor S and the Jacobi operator $R_\xi$ with respect to the structure vector $\xi$.

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