A note on the role of zero-point energy in evolutionary cosmology

Following a suggestion originally due to McCrea, a physical vacuum is regarded as the ground state of a certain quantized field obeying Bose statistics. Under certain assumptions regarding the physical nature of the zero-point energy (assumed to be essentially positive) associated with the Bose field, the latter is found to result in an effectively negative kinematic pressure p having the functional dependence of the form p varies as G-4, where G is the curvature of space. This leads naturally to an oscillating isotropic model of the universe without singularity, of the type treated in detail by Pachner. In effect, the purely mathematical artifice of assuming negative pressure is given a physical basis in terms of the zero-point energy considerations