Axion inflation with cross-correlated axion isocurvature perturbations

作者:Kadota Kenji; Kobayashi Tatsuo; Otsuka Hajime
来源:Journal of Cosmology and Astroparticle Physics, 2016, 2016(1): 044.
DOI:10.1088/1475-7516/2016/01/044

摘要

We study the inflation scenarios, in the framework of superstring theory, where the inflaton is an axion producing the adiabatic curvature perturbations while there exists another light, axion producing the isocurvature perturbations. We discuss how the non-trivial couplings among string axions can generically arise, and calculate the consequent cross-correlations between the adiabatic and isocurvature modes through concrete examples. Based on the Planck analysis on the generally correlated isocurvature perturbations, we show that there is a preference for the existence of the correlated isocurvature modes for the axion monodromy inflation while the natural inflation disfavors such isocurvature modes.

  • 出版日期2016-1