The Implications of N =2 Supergravity Cosmology On the Topology of the Calabi-Yau Manifold

Abstract

When N= D=11 supergravity is compactified on CY threefold to N=2 D=5 supergravity the action of the last is given in terms of the geometery of the CY manifold space, namely, in terms of the hypermultiplets. There are $z^i(i=1,...,h^{2,1})$ complex structure moduli in the moduli space of the CY manifold which is a special K\"ahler manifold with a metric $G_{i\bar{j}}$. We solve the field equations of the complex structure moduli with the solution of the Einstein field equations to the moduli velocity norm $G_{i\bar{j}} z^i z^{\bar{j}}$ in case of a 3- brane filled with radiation, dust and energy embedded in the bulk of D=5 supergravity. We get the time dependence of the moduli and the metric. Then we can further deduce the geometry of the moduli space by getting the K\"ahler potential which directly relates to the volume of the CY manifold.