DECAYING VACUUM ENERGY AND DEFLATIONARY COSMOLOGY IN OPEN AND CLOSED UNIVERSES

We consider a nonsingular deflationary cosmological model with a decay ing vacuum energy density in universes of arbitrary spatial curvature. Irrespective of the value of k, the models are characterized by an ar bitrary time scale H-I(-1) which determines the initial temperature of the universe and the largest value of the vacuum energy density, the slow decay of which generates all the presently observed matter energy of the Universe. If H-I(-1) is of the order of the Planck time, the m odels begin with the Planck temperature and the present day value of t he cosmological constant satisfies Lambda(I)/Lambda(0) similar or equa l to 10(118) as theoretically suggested. It is also shown that all mod els allow a density parameter Omega(0) < 2/3 and that the age of the U niverse is large enough to agree with observations even with the high value of H-0 suggested by recent measurements.