Abstract
We continue here the study initiated in [9] on the harmonicity of certain geometric objects on the total space TM of the tangent bundle of a Riemannian space form (M(c), g). Precisely, in this paper we find all the general natural metrics on TM, with respect to which the canonical almost complex structure J on TM is harmonic. We also study the harmonicity of this tensor field with respect to the natural diagonal metrics. In particular, we obtain that J is harmonic with respect to the Sasaki metric on TM if and only if the base manifold is flat.
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Dedicated to the memory of Professor Mircea Craioveanu.
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Bejan, CL., Druţă-Romaniuc, SL. Harmonic Almost Complex Structures with Respect to General Natural Metrics. Mediterr. J. Math. 11, 123–136 (2014). https://doi.org/10.1007/s00009-013-0302-0
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DOI: https://doi.org/10.1007/s00009-013-0302-0