Abstract
The first author defended her doctoral thesis “Espacios homogéneos reductivos y álgebras no asociativas” in 2001, supervised by P. Benito and A. Elduque. This thesis contained the classification of the Lie-Yamaguti algebras with standard envelo** algebra \(\mathfrak {g}_2\) over fields of characteristic zero, which in particular gives the classification of the homogeneous reductive spaces of the compact Lie group \(G_2\). In this work we revisit this classification from a more geometrical approach. We provide too geometric models of the corresponding homogeneous spaces and make explicit some relations among them.
Partially supported by Junta de Andalucía projects FQM-336, UMA18-FEDERJA-119 and P20_01391, and by the Spanish MICINN projects PID2019-104236GB-I00/AEI/10.13039/501100011033 and PID2020-118452GB-I00, all of them with FEDER funds.
Partially supported by Spanish MICINN project PID2020-118452GB-I00 and Andalusian and ERDF projects FQM-494 and P20\(_{-}\)01391.
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Notes
- 1.
Note that l and r correspond to − and \(+\), respectively, in the literature.
- 2.
Be careful with the typo in that formula in [39, Proposition 2.4].
- 3.
Note that, if \(J^2=-\textrm{id}\), then \(J\in \textrm{SO}(W)\) if and only if \(J\in \mathfrak {so}(W)\).
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Draper, C., Palomo, F.J. (2023). Reductive Homogeneous Spaces of the Compact Lie Group \(G_2\). In: Albuquerque, H., Brox, J., Martínez, C., Saraiva, P. (eds) Non-Associative Algebras and Related Topics. NAART 2020. Springer Proceedings in Mathematics & Statistics, vol 427. Springer, Cham. https://doi.org/10.1007/978-3-031-32707-0_3
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