  The cosmological constant problem is explained by a theory based on the
discrete space-time hypothesis. The calculated cosmological constant value is
of the order of 10^-52[m]^-2 or equivalent to about 0.7 of the critical mass
density. It is in excellent agreement with Type Ia SN observational data and
recent results of BOOMERANG and MAXIMA. Our theory also implies that the
quantization of the space-time metric is not necessary since it is not a
fundamental field. The divergence problem of quantum gravity is then of no
interest. Cosmic inflation is given out as a consequence of the theory and the
universe is found to be alternatively dominated by the cosmological constant
and the mass density at different cosmic time period. Our calculation also
shows that the mass energy density is of similar order of magnitude as the
vacuum energy density in the present universe but it is just a coincidence.
This result supports the anthropic principle.
