  In this approach to discrete quantum gravity the basic structural element is
a covariant causal set ($c$-causet). The geometry of a $c$-causet is described
by a shell-sequence that determines the discrete gravity of a universe. In this
growth model, universes evolve in discrete time by adding new vertices to their
generating $c$-causet. We first describe an inflationary period that is common
to all universes. After this very brief cycle, the model enters a multiverse
period in which the system diverges in various ways forming paths of
$c$-causets. At the beginning of the multiverse period, the structure of a
four-dimensional discrete manifold emerges and quantum mechanics enters the
picture. A natural Hilbert space is defined and a discrete, free Dirac operator
is introduced. We determine the eigenvalues and eigenvectors of this operator.
Finally, we propose values for coupling constants that determine multiverse
probabilities. These probabilities predict the dominance of pulsating
universes.
