  The nature of cosmic time is illuminated using Hamilton-Jacobi theory for
general relativity. For problems of interest to cosmology, one may solve for
the phase of the wavefunctional by using a line integral in superspace. Each
contour of integration corresponds to a particular choice of time hypersurface,
and each yields the same answer. In this way, one can construct a covariant
formalism where all time hypersurfaces are treated on an equal footing. Using
the method of characteristics, explicit solutions for an inflationary epoch
with several scalar fields are given. The theoretical predictions of double
inflation are compared with recent galaxy data and large angle microwave
background anisotropies.
