Abstract
This paper considers invariant almost Hermitian structures on a flag manifold G / P = U / K where G is a complex semi-simple Lie group, P is a parabolic subgroup of G, U is a compact real form of G and K = U ∩ P is the centralizer of a torus. The main result shows that there are nearly-Kähler structures in G / P which are not Kähler if and only if G / P has height two. This proves for the flag manifolds a conjecture by Wolf and Gray.
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Martin, L.A.B.S., Silva, R.d.C.d.J. Invariant nearly-Kähler structures. Geom Dedicata 121, 143–154 (2006). https://doi.org/10.1007/s10711-006-9095-7
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DOI: https://doi.org/10.1007/s10711-006-9095-7