Scale-dependent CMB asymmetry from primordial configuration

Understand

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.