Proceedings of the International Geometry Center

ISSN-print: 2072-9812
ISSN-online: 2409-8906
ISO: 26324:2012
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A (CHR)3-flat trans-Sasakian manifold

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Koji Matsumoto
http://orcid.org/0000-0003-3312-8564

Abstract

In [4] M. Prvanovic considered several curvaturelike tensors


defined for Hermitian manifolds. Developing her ideas in [3], we defined in an almost contact Riemannian manifold another new curvaturelike tensor field, which is called a contact holomorphic Riemannian curvature tensor or briefly (CHR)3-curvature tensor. Then, we mainly researched (CHR)3-curvature tensor in a Sasakian manifold. Also we proved, that a conformally (CHR)3-flat Sasakian manifold does not exist. In the present paper, we consider this tensor field in a trans-Sasakian manifold. We calculate the (CHR)3-curvature tensor in a trans-Sasakian manifold. Also, the (CHR)3-Ricci tensor ρ3  and the (CHR)3-scalar curvature τ3  in a trans-Sasakian manifold have been obtained. Moreover, we define the notion of the (CHR)3-flatness in an almost contact Riemannian manifold. Then, we consider this notion in a trans-Sasakian manifold and determine the curvature tensor, the Ricci tensor and the scalar curvature. We proved that a (CHR)3-flat trans-Sasakian manifold is a generalized   ɳ-Einstein manifold. Finally, we obtain the expression of the curvature tensor with respect to the Riemannian metric g of a trans-Sasakian manifold, if the latter is (CHR)3-flat.

Keywords:
(CHR)3-curvature tensor; trans-Sasakian manifold; (CHR)3-flat almost contact Riemannian manifold; (generalized) ɳ-Einstein manifold

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How to Cite
Matsumoto, K. (2019). A (CHR)3-flat trans-Sasakian manifold. Proceedings of the International Geometry Center, 12(2), 11–25. https://doi.org/10.15673/tmgc.v12i2.1438
Section
Papers
Author Biography

Koji Matsumoto, Yamagata University

Professor, Emeritus

References

Література *
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