| Title: | On skew 2-projectable almost complex structures on $TM$ (English) | 
| Author: | Dekrét, Anton | 
| Language: | English | 
| Journal: | Archivum Mathematicum | 
| ISSN: | 0044-8753 (print) | 
| ISSN: | 1212-5059 (online) | 
| Volume: | 34 | 
| Issue: | 2 | 
| Year: | 1998 | 
| Pages: | 285-293 | 
| Summary lang: | English | 
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| Category: | math | 
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| Summary: | We deal with a $(1, 1)$-tensor field $\alpha $ on the tangent bundle $TM$ preserving vertical vectors and such that $J\alpha =-\alpha J$ is a $(1, 1)$-tensor field on $M$, where $J$ is the canonical almost tangent structure on $TM$. A connection $\Gamma _{\alpha }$ on $TM$ is constructed by $\alpha $. It is shown that if $\alpha $ is a $VB$-almost complex structure on $TM$ without torsion then $\Gamma _{\alpha }$ is a unique linear symmetric connection such that $\alpha (\Gamma _{\alpha })=\Gamma _{\alpha }$ and $\nabla _{\Gamma _{\alpha }} (J\alpha ) =0$. (English) | 
| Keyword: | tangent bundle | 
| Keyword: | skew 2-projectable | 
| Keyword: | $(1, 1)$-vector fields | 
| Keyword: | almost complex structure | 
| Keyword: | connection | 
| MSC: | 53C05 | 
| MSC: | 53C15 | 
| MSC: | 58A20 | 
| idZBL: | Zbl 0910.53020 | 
| idMR: | MR1645324 | 
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| Date available: | 2009-02-17T10:12:04Z | 
| Last updated: | 2012-05-10 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/107653 | 
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