Probing new physics with multi-vacua quantum tunnelings beyond standard model through gravitational waves

Understand

We report on a novel phenomenon of particle cosmology, which features specific cosmological phase transitions via quantum tunnelings through multiple vacua.

• The latter is inspired by the axiverse ideas and enables us to probe the associated new physics models through a potential observation of specific patterns in the stochastic gravitational waves background.
• Multiple vacua may induce the nucleation of co-existing bubbles over the phase transition epoch, hence enhancing the overall process of bubbles' nucleation.
• Our detailed analysis of semi-analytical and numerical solutions to the bounce equations of the path integral in three vacua case has enabled us to determine the existence of three instanton solutions.