Article

# Relating the curvature tensor and the complex Jacobi operator of an almost Hermitian manifold

12/2006;
Source: arXiv

ABSTRACT Let J be a unitary almost complex structure on a Riemannian manifold (M,g). If x is a unit tangent vector, let P be the associated complex line spanned by x and by Jx. We show that if (M,g) is Hermitian or if (M,g) is nearly Kaehler, then either the complex Jacobi operator (JC(P)y=R(y,x)x+R(y,Jx)Jx) or the complex curvature operator (RC(P)y=R(x,Jx)y) completely determine the full curvature operator; this generalizes a well known result in the real setting to the complex setting. We also show this result fails for general almost Hermitian manifold.

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### Keywords

associated complex line spanned

complex curvature operator

complex Jacobi operator

full curvature operator

Jx

Riemannian manifold

unitary