Generalized Compactification and Assisted Dynamics of Multi--Scalar Field Cosmologies

Cosmological models arising from a generalized compactification of Einstein gravity are derived. It is shown that a redefinition of the moduli fields reduces the system to a set of massless fields and a single field with a single exponential potential, independent of the background spacetime. This solution is the unique late–time attractor for an arbitrary spacetime dimensionality. We find that if the number of dimensions is greater than or equal to seven, the scalar fields dominate a relativistic fluid and therefore constitute a potential `moduli’ problem.