Abstract
The existence or nonexistence of a complex structure on \(\mathrm{S}^6\) was a long standing unsolved problem. There is a well-known orbit \(O(\varLambda )\) in \(G_2\) which is diffeomorphic to \(\mathrm{S}^6\) and used by Gábor Etesi in an effort to find a complex structure. Etesi suggested to give a complex structure in \(\mathrm{S}^6\) through this orbit. In Daniel Guan’s earlier paper, he proved that the orbit can not be a complex submanifold. Since there was not a clear description of the map from \(O(\varLambda )\) to \(\mathrm{S}^6\) in that paper, we give another clearer, simpler and explicit proof of that result in this paper.
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The funding was provided by National Nature Science Foundation of China (Grant Nos. 11901157, 11971353, 12171140), China Postdoctoral Science Foundation (Grant No. 2020M680096).
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This research was supported by National Nature Science Foundation of China (Grant No.12171140), and partially supported by National Nature Science Foundation of China (Grant No.11901157, 11971353), and China Postdoctoral Science Foundation (2020M680096)
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Guan, D., Wang, Z. A Note On the Nonexistence of a Complex Threefold as a Conjugate Orbit of \(G_2\). Results Math 77, 139 (2022). https://doi.org/10.1007/s00025-022-01678-5
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DOI: https://doi.org/10.1007/s00025-022-01678-5
Keywords
- Complex structure
- six dimensional sphere
- cohomology
- invariant structure
- complex torus bundles
- hermitian manifolds