Effective Couplings of Grand Unified Theories in Curved Space-Time

Abstract
The curved—space-time generalizations of SU(5) grand unified theories are considered. The high-curvature limit of the effective gravitational and cosmological constants, as well as other coupling constants not present in flat space-time, is studied using renormalization-group methods. These effective coupling constants appear in the gravitational field equations and may have important cosmological implications.