Baryogenesis and Gravitational Waves from Runaway Bubble Collisions

Understand

We propose a novel mechanism for production of baryonic asymmetry in the early Universe.

• The mechanism takes advantage of the strong first order phase transition that produces runaway bubbles in the hidden sector that propagate almost without friction with ultra-relativistic velocities.
• Collisions of such bubbles can non-thermally produce heavy particles that further decay out-of-equilibrium into the SM and produce the observed baryonic asymmetry.
• This process can proceed at the very low temperatures, providing a new mechanism of post-sphaleron baryogenesis.