CAN SEMICLASSICAL WORMHOLES SOLVE THE COSMOLOGICAL HORIZON PROBLEM

Measurements of the cosmic microwave background (CMB) radiation provid e the strongest evidence for the isotropy of the observable universe o n the largest scales. However, the CMB is received from regions which were not in casual contact at the time of last scattering. This is the horizon problem and the generally accepted solution is to invoke an i nflationary period in the early universe. We consider the possibility that the universe did not necessarily inflate, but was filled with a n etwork of evolving wormholes connecting otherwise causally disjoint re gions. These worm-holes emerged naturally from the Planck epoch and ne ed only have stayed open for a very brief time (deltat < 10(-34) sec) in order to have thermalized the early universe.