Coleman-Weinberg SO(10) GUT Theories as Inflationary Models

The flat-space limit of the one-loop effective potential for SO(10) GUT theories in spatially flat Friedmann-Robertson-Walker cosmologies is applied to study the dynamics of the early universe. The numerical integration of the corresponding field equations shows that, for such grand unified theories, a sufficiently long inflationary stage is achieved for suitable choices of the initial conditions. However, a severe fine tuning of these initial conditions is necessary to obtain a large e-fold number. In the direction with residual symmetry SU(4)PS ⊗ SU(2)L ⊗ SU(2)R, one eventually finds parametric resonance for suitable choices of the free parameters of the classical potential. This phenomenon leads in turn to the end of inflation. 02.60.Cb, 03.70.+k, 11.15.Ex, 98.80.Cq Typeset using REVTEX Electronic address: [email protected] Electronic address: [email protected] Electronic address: [email protected]