| Title: | Isotropic almost complex structures and harmonic unit vector fields (English) | 
| Author: | Baghban, Amir | 
| Author: | Abedi, Esmaeil | 
| Language: | English | 
| Journal: | Archivum Mathematicum | 
| ISSN: | 0044-8753 (print) | 
| ISSN: | 1212-5059 (online) | 
| Volume: | 54 | 
| Issue: | 1 | 
| Year: | 2018 | 
| Pages: | 15-32 | 
| Summary lang: | English | 
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| Category: | math | 
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| Summary: | Isotropic almost complex structures $J_{\delta , \sigma }$ define a class of Riemannian metrics $g_{\delta , \sigma }$ on tangent bundles of Riemannian manifolds which are a generalization of the Sasaki metric. In this paper, some results will be obtained on the integrability of these almost complex structures and the notion of a harmonic unit vector field will be introduced with respect to the metrics $g_{\delta , 0}$. Furthermore, the necessary and sufficient conditions for a unit vector field to be a harmonic unit vector field will be obtained. (English) | 
| Keyword: | complex structures | 
| Keyword: | energy functional | 
| Keyword: | isotropic almost complex structure | 
| Keyword: | unit tangent bundle | 
| Keyword: | variational problem | 
| Keyword: | tension field | 
| MSC: | 53C15 | 
| MSC: | 53C43 | 
| idZBL: | Zbl 06861555 | 
| idMR: | MR3783289 | 
| DOI: | 10.5817/AM2018-1-15 | 
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| Date available: | 2018-03-12T13:43:07Z | 
| Last updated: | 2020-01-05 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/147107 | 
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