M theory compactification, fluxes and AdS(4)

We analyze supersymmetric solutions of M-theory based an a seven-dimensional internal space with SU(3) structure and a four-dimensional maximally symmetric space. The most general supersymmetry conditions are derived and we show that a nonvanishing cosmological constant requires the norms of the two internal spinors to differ. We find explicit local solutions with singlet flux and the space being a warped product of a circle, a nearly Kaehler manifold and AdS{sub 4}. The embedding of solutions into heterotic M-theory is also discussed.