A predictive inflationary scenario without the gauge singlet

Abstract

We propose a new realization of the chaotic inflationary scenario in which the scalar field responsible for inflation also spontaneously breaks the underlying gauge symmetry at a superheavy scale ∼ 10 15–10 17 GeV. A possible framework is provided by the superstrings inspired gauge models, in which case several predictions are essentially model independent. The spectral index for the scalar perturbations n⋍0.92−0.88, while the ratio of the tensor to the scalar quadrupole anisotropy is (ΔT/T) 2 T (ΔT/T) 2 S ≈ 0.4−0.7 . On smaller angular scales, σT/ T(1°) ≈ (9−16) × 10 −6 and σT/ T(2.1°) ≈ (6−10) × 10 −6. Implications for magnetic monopoles and cosmic strings as well as the gauge hierarchy problem are pointed out.