On seven dimensional 3-Sasakian manifolds

Year 2016, , 127 - 136, 01.02.2016

Nilüfer Özdemir

https://doi.org/10.1501/Commua1_0000000748

Abstract

3-Sasakian manifolds in dimension seven have cocalibrated andnearly parallel G-structures. In this work, cocalibrated G-structure is deformed by one of the characteristic vector fields of the 3-Sasakian structure anda new G2structure is obtained whose metric has negative scalar curvature. Inaddition, the new G2structure has a nonzero Killing vector field. Then, by using this deformation, new covariant derivative on the spinor bundle is obtained and the new Dirac operator is written in terms of the Dirac operator before deformation

Keywords

3-Sasakian manifold, Riemannian manifold with structure group G2

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• Current address : Department of Mathematics, Anadolu University, 26470 Eski¸sehir, Turkey E-mail address : [e-mail]