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arXiv · 1006.5684

Investigation of all Ricci semi-symmetric and all conformally semi-symmetric spacetimes

Jan E. Åman
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Abstract

We find all Ricci semi-symmetric as well as all conformally semi-symmetric spacetimes. Neither of these properties implies the other. We verify that only conformally flat spacetimes can be Ricci semi-symmetric without being conformally semi-symmetric and show that only vacuum spacetimes and spacetimes with just a $Λ$-term can be Ricci semi-symmetric without being conformally semi-symmetric.

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Jan E. Åman. 2010-09-03. Investigation of all Ricci semi-symmetric and all conformally semi-symmetric spacetimes. https://doi.org/10.1088/1742-6596%2F314%2F1%2F012020

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