Inflation with Conformally Coupled Scalar Field

In a Robertson-Walker geometry conformally coupled to a scalar field with inflation potential V() = M⁴- (1/4)λ⁴, we investigate the classical evolution of a universe. The exact solutions in the model have been found. It is shown that in the region where the value of the p field is 0 <  < _max, (_max is the solution of V() = 0), there is inflation. This model can lead to successful inflation with λ ~ 10^-9, rather than 10^-13as previously reported.