  When the scale factor of expansion of the universe is written as $ a(t)\equiv
Ae^{\alpha(t)}$, with $A$ as some real constant and $\alpha(t)$ a real
function, the gravitational action $I_G$ appears in the same form as the matter
action $I_M$ for a homogeneous and isotropic scalar field with a specific scale
factor-dependent potential. We observe that by making analytic continuation of
the Lagrangian function in this $I_G$ to the complex plane of $\alpha$, one can
obtain terms corresponding to both parts of a total action that describes a
viable cosmological model. The solution gives a bouncing and coasting universe,
which first contracts and then expands linearly, with a smooth bounce in
between them. Such a bounce, called a Tolman wormhole, is due to a Casimir-like
negative energy that appears naturally in the solution. In a novel approach to
quantum cosmology, we perform canonical quantization of the above model using
the operator method and show that it can circumvent the operator ordering
ambiguity in the conventional formalism. It leads to a quantum wave equation
for the universe, solving which we get the interesting result that the universe
is in a ground state with nonzero energy. This solution is different from the
Wheeler-DeWitt wave function and possesses exact quantum-classical
correspondence during all epochs.
