INHOMOGENEOUS COSMOLOGICAL MODELS IN D=6, N=2 KALUZA-KLEIN SUPERGRAVITY

We obtain a cosmological solution in an (RXRXS2)-X-1-X-3 spacetime for an inhomogeneous distribution of matter obeying an equation of state, p = -rho not equal p(1) , where p and p(1) are the isotropic pressure s-in the 3-space and extra space, respectively. Our model admits expon ential expansion of the three-dimensional (3D) space, while the extra space is amenable to dimensional reduction. Interestingly, aside from the well known singularity at the big bang:our inhomogeneous solutions are spatially regular everywhere, including the center of symmetry r = 0. Moreover, our model seems to suggest an alternative mechanism poi nting to a smooth transition from a primorial multidimensional, inhomo geneous phase-to a 4D homogeneous one.