PHASE TRANSITIONS IN HIGHER DIMENSIONAL COSMOLOGY

We have considered five-dimensional massive scalar field coupled to gravity and evaluated the one-loop effective potential in higher dimensions. It is demonstrated that nonminimally coupled phi(4) theory can be regularized in five dimensions. Temperature dependent one-loop correction and critical temperature beta(c) are computed. The phase transitions in the early universe depend on the space-time curvature R and scalar gravitational coupling xi. A brief discussion of symmetry restoration is also presented and the nature of phase transitions in the early universe is found to be of second order.