Scale-dependent CMB asymmetry from primordial configuration

Abstract

We demonstrate that a topological defect can explain the hemispherical power asymmetry of the CMB. The first point is that a defect configuration, which already exists prior to inflation, can source asymmetry of the CMB. The second point is that modulation mechanisms, such as the curvaton and other modulation mechanisms, can explain scale-dependence of the asymmetry. Using a simple analysis of the $\delta N$ formalism, we show models in which scale-dependent hemispherical power asymmetry is explained by primordial configuration of a defect.