Narrow Results

The present work focuses on the scalar and electromagnetic fields in a spatially closed FRW Universe with incoherent dust. First, as the complex scalar field is under consideration, we derive the general solutions of the Gordon equation, in terms of the positive-frequency-like parity modes, and the corresponding propagator. Secondly, we turn to the source-free Maxwell equations in order to find a (1 + 4)-parametric class of closed form solutions representing a non-propagating fundamental electric field and a burst of electromagnetic radiation.

In the spacetime described by a metric with g₄₄ = -cosh²(αz), we are pointing out some unusual (pathological) features as for example a genuine temporal imprisonment of null geodesics. For the massless bosons evolving in such an Universe, we solve the Gordon equation and derive the characteristic function and the main thermodynamic quantities.