Abstract
In this paper, we study invariant Einstein metrics on certain compact homogeneous spaces with three isotropy summands. We show that, if G/K is a compact isotropy irreducible space with G and K simple, then except for some very special cases, the coset space G × G=Δ(K) carries at least two invariant Einstein metrics. Furthermore, in the case that G1;G2 and K are simple Lie groups, with K ⊂ G1;K ⊂ G2, and G1 ≠ G2, such that G1/K and G2/K are compact isotropy irreducible spaces, we give a complete classification of invariant Einstein metrics on the coset space G1 × G2=Δ(K).
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Acknowledgements
This work was supported by National Natural Science Foundation of China (Grant Nos. 11401425, 11626134, 11701300, 11671212 and 51535008) and K. C. Wong Magna Fund in Ningbo University.
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Yan, Z., Chen, H. & Deng, S. Classification of invariant Einstein metrics on certain compact homogeneous spaces. Sci. China Math. 63, 755–776 (2020). https://doi.org/10.1007/s11425-018-9357-1
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DOI: https://doi.org/10.1007/s11425-018-9357-1