Abstract
We determine a new class of paracontact paracomplex Riemannian manifolds derived from certain cone construction, called para-Sasaki-like Riemannian manifolds, and give explicit examples. We define a hyperbolic extension of a paraholomorphic paracomplex Riemannian manifold, which is a local product of two Riemannian spaces of equal dimension, and show that it is a para-Sasaki-like Riemannian manifold. If the original paraholomorphic paracomplex Riemannian manifold is a complete Einstein space of negative scalar curvature, then its hyperbolic extension is a complete Einstein para-Sasaki-like Riemannian manifold of negative scalar curvature. Thus, we present new examples of complete Einstein Riemannian manifolds of negative scalar curvature.
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Acknowledgements
The research of S.I. is partially supported by Contract DH/12/3/12.12.2017, Contract 80-10-161/05.04.2021 with the Sofia University “St. Kliment Ohridski” and the National Science Fund of Bulgaria, National Scientific Program “VIHREN”, Project no. KP-06-DV-7. The research of H. M. is partially supported by the National Scientific Program “Young Researchers and Post-Doctorants” and the project MU21-FMI-008 of the Scientific Research Fund, University of Plovdiv “Paisii Hilendarski”. The research of M. M. is partially supported by projects MU21-FMI-008 and FP21-FMI-002 of the Scientific Research Fund, University of Plovdiv “Paisii Hilendarski”.
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Ivanov, S., Manev, H. & Manev, M. Para-Sasaki-like Riemannian manifolds and new Einstein metrics. RACSAM 115, 112 (2021). https://doi.org/10.1007/s13398-021-01053-z
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DOI: https://doi.org/10.1007/s13398-021-01053-z
Keywords
- Almost paracontact Riemannian manifolds
- Holomorphic paracomplex manifold
- Para-Sasaki-like manifolds
- Einstein manifolds