Small non-Gaussianity and dipole asymmetry in the CMB

Understand

In this paper we provide a prescription for obtaining a small non-Gaussianity and the observed dipole asymmetry in the cosmic microwave background radiation.

• The observations inevitably lead to multi-field inflationary dynamics, where each field can create positive or negative large non-Gaussianity, resulting a fine cancellation but with an observable imprint on the hemispherical asymmetry.
• We discuss this possibility within a simple slow-roll scenario and find that it is hard to explain the observed dipole asymmetry.
• We briefly discuss some speculative scenarios where one can explain dipole asymmetry.