Nambu-Goldstone Affleck-Dine Baryogenesis

Understand

The Affleck-Dine mechanism creates the baryon asymmetry of the universe from an angular motion of a complex scalar field.

• The mechanism is efficient and allows for a low reheating temperature of the universe if the scalar field has a flat potential along its radial direction.
• We consider a possibility where the scalar field is a pseudo-Nambu-Goldstone boson arising from spontaneous breaking of an approximate global symmetry, so that the flatness of the potential is naturally understood.
• We construct a concrete realization of the idea based on chiral symmetry breaking in an SU(N) gauge theory.