  We started the evolution of a flat universe from a nonsingular state called
prematter which is governed by an inflationary equation of state
$P=(\gamma_{p}-1)\rho$ where $\gamma_{p}$ represents the initial vacuum
dominance of the universe. The evolution of the universe-except in the
prematter era-is affected neither by the initial vacuum dominance nor the
initial expansion rate of the universe. On the other hand, present properties
of the universe such as Hubble constant, age and density are sensitive to the
temperature at the decoupling $(T_{m})$. Over a range between $3\cdot10^{4}$
and $5\cdot10^{4}$ K for $(T_{m})$, our model predicts a value between 50 and
80 $Km\cdot sec^{-1}\cdot Mpc^{-1}$ for the present value of the Hubble
constant $(H_{0})$. Assuming that the thermal history of the universe is
independent from its geometry, the above range could be considered as
transition range for the decoupling temperature $(T_{m})$.
