Abstract
We give a short Lie-derivative theoretic proof of the following recent result of Barros et al. “A compact non-trivial almost Ricci soliton with constant scalar curvature is gradient, and isometric to a Euclidean sphere”. Next, we obtain the result: a complete almost Ricci soliton whose metric \(g\) is \(K\)-contact and flow vector field \(X\) is contact, becomes a Ricci soliton with constant scalar curvature. In particular, for \(X\) strict, \(g\) becomes compact Sasakian Einstein.
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Acknowledgments
The author thanks the referees for numerous constructive suggestions. This work has been supported by University Research Scholarship of the University of New Haven.
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Communicated by A. Cap.
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Sharma, R. Almost Ricci solitons and \(K\)-contact geometry. Monatsh Math 175, 621–628 (2014). https://doi.org/10.1007/s00605-014-0657-8
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DOI: https://doi.org/10.1007/s00605-014-0657-8
Keywords
- Almost Ricci soliton
- Conformal vector field
- Constant scalar curvature
- \(K\)-Contact metric
- Einstein Sasakian metric