Systematics of constant roll inflation

作者：Anguelova Lilia^*; Suranyi Peter; Wijewardhana L C R

来源：Journal of Cosmology and Astroparticle Physics, 2018, 2018(2): 004.

DOI：10.1088/1475-7516/2018/02/004

• inflation
• cosmological perturbation theory
• physics of the early universe

We study constant roll inflation systematically. This is a regime, in which the slow roll approximation can be violated. It has long been thought that this approximation is necessary for agreement with observations. However, recently it was understood that there can be inflationary models with a constant, and not necessarily small, rate of roll that are both stable and compatible with the observational constraint n(s) approximate to 1. We investigate systematically the condition for such a constant-roll regime. In the process, we find a whole new class of inflationary models, in addition to the known solutions. We show that the new models are stable under scalar perturbations. Finally, we find a part of their parameter space, in which they produce a nearly scale-invariant scalar power spectrum, as needed for observational viability.

• 出版日期2018-2