Spontaneous Baryogenesis without Baryon Isocurvature

Understand

We propose a new class of spontaneous baryogenesis models that does not produce baryon isocurvature perturbations.

• The baryon chemical potential in these models is independent of the field value of the baryon-generating scalar, hence the scalar field fluctuations are blocked from propagating into the baryon isocurvature.
• We demonstrate this mechanism in simple examples where spontaneous baryogenesis is driven by a non-canonical scalar field.
• The suppression of the baryon isocurvature allows spontaneous baryogenesis to be compatible even with high-scale inflation.