Multiple Production of Bianchi Type-I Universes

The procedure similar to an ordinary quantum field theory in curved spacetime is applied to study the Bianchi type-I universes with a radiation field source. The Wheeler-De Witt equation satisfied by the cosmological wave function is found. After the wave function was regarded as a universe field in
the minisuperspace, not only the difficulty in a probabilistic interpretation in the quantum cosmology can be circumvented, but also the conclusion of the multiple production of universes is obtained, and the average number of various universes created from 'nothing' is estimated.