Non-Gaussianity in single field models without slow-roll conditions

作者：Noller Johannes^*; Magueijo Joao

来源：Physical Review D - Particles, Fields, Gravitation and Cosmology, 2011, 83(10): 103511.

DOI：10.1103/PhysRevD.83.103511

We investigate non-Gaussianity in general single field models without assuming slow-roll conditions or the exact scale invariance of the scalar power spectrum. The models considered include general single field inflation (e. g. Dirac-Born-Infeld and canonical inflation) as well as bimetric models. We compute the full non-Gaussian amplitude A, its size f(NL), its shape, and the running with scale n(NG). In doing so we show that observational constraints allow significant violations of slow-roll conditions and we derive explicit bounds on slow-roll parameters for fast-roll single field scenarios. A variety of new observational signatures is found for models respecting these bounds. We also explicitly construct concrete model implementations giving rise to this new phenomenology.

• 出版日期2011-5-6