I have been told that the following is an open problem in mathematics, but I am pretty sure that experts in the topic surely know the answer.
Is the manifold
$$M=\frac{E_{7(7)}}{SU(7)}\times \mathbb{R}^{+}$$
a (pseudo)Kähler-Hodge manifold? Just to be clear, by this I mean if $M$ can be equipped with a (pseudo)Kähler structure, namely a complex structure $J$, a symplectic structure $\omega$ and a compatible metric $g$ (of indefinite signature) such that $\omega$ is integral, that is, $[\omega] \in H^{2}(M,\mathbb{Z})$, together with a hermitian line-bundle $\mathcal{L}\to M$ such that its first Chern class is
$c_{1}(\mathcal{L}) = [\omega]$
$E_{7(7)}$ refers to the split real form of $E_{7}$.
Thanks.
Edit: I have been required to provide the reference that states this as an open problem. Here it is:
http://arxiv.org/abs/0804.1362
(see section 3.3) That reference also explains the relevance of this problem in describing the moduli space of M-theory flux compactifications on seven-dimensional manifolds.