KALUZA-KLEIN THEORY AND MACHIAN COSMOLOGY

We interpret the 15 equations of Kaluza-Klein gravity as 10 Einstein e quations, 1 wave equation and 4 equations of motion. An exact cosmolog ical solution of the apparently empty 5D field equations describes a 4 D fluid with an effective density and pressure induced by the curvatur e associated with the fifth dimension. The rest mass of a particle in the fluid depends on the global solution and changes slowly with time. This approach to Kaluza-Klein theory in general results in Machian co smologies.