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On the PSL(2,19)-invariant cubic sevenfold

It has been proved by Adler that there exists a unique cubic hypersurface X in P^8 which is invariant under the action of the simple group PSL(2,19). In the present note we study the intermediate Jacobian of X and in particular we prove that the subjacent 85-dimensional torus is an Abelian variety. The symmetry group G=PSL(2,19) defines uniquely a G-invariant abelian 9-fold A(X), which we study in detail and describe its period lattice.