  Recent AC susceptibility and polar Kerr effect measurements in the
skutterudite superconductor PrOs4Sb12 (POS) uncovered the nature of the
superconducting double transition from a high temperature, high field, time
reversal symmetric phase (or the A phase) to a low temperature, low field, time
reversal symmetry broken phase (or the B phase). Starting from a microscopic
model, we derive a Ginzburg-Landau expansion relevant to POS that describes
this entrance into the time reversal symmetry broken phase along the
temperature axis. We also provide a study of the low energy inelastic (Raman)
response in both the A and B phases of POS, and seek additional signatures
which could help reveal the exact form of the gap functions previously proposed
in these phases. By appropriately manipulating the incoming and scattered light
geometries, along with additional subtraction procedures and suitable
assumptions, we show that one can access the various irreducible
representations contained in the point group describing POS. We demonstrate how
to use this technique on example order parameters proposed in POS. Depending on
whether there exist nodes along the c-axis, we find additional low energy
spectral weight within the superconducting gap in the Eg geometry, a feature
that could pin point the location of nodes on the Fermi surface.
