Distinguished connections on $(J^{2}=\pm 1)$-metric manifolds

Fernando Etayo; Rafael Santamaría

doi:10.5817/am2016-3-159

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arXiv · 1601.05231

Distinguished connections on $(J^{2}=\pm 1)$-metric manifolds

Fernando Etayo·Rafael Santamaría

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Abstract

We study several linear connections (the first canonical, the Chern, the well adapted, the Levi Civita, the Kobayashi-Nomizu, the Yano, the Bismut and those with totally skew-symmetric torsion) which can be defined on the four geometric types of $(J^2=\pm1)$-metric manifolds. We characterize when such a connection is adapted to the structure, and obtain a lot of results about coincidence among connections. We prove that the first canonical and the well adapted connections define a one-parameter family of adapted connections, named canonical connections, thus extending to almost Norden and almost product Riemannian manifolds the families introduced in almost Hermitian and almost para-Hermitian manifolds. We also prove that every connection studied in this paper is a canonical connection, when it exists and it is an adapted connection.

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Fernando Etayo, Rafael Santamaría. 2016-01-20. Distinguished connections on $(J^{2}=\pm 1)$-metric manifolds. https://doi.org/10.5817/am2016-3-159

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