Metastability of the False Vacuum in a Higgs-Seesaw Model of Dark Energy

Understand

In a recently proposed Higgs-Seesaw model the observed scale of dark energy results from a metastable false vacuum energy associated with mixing of the standard model Higgs particle and a scalar associated with new physics at the GUT or Planck scale.

• Here we address the issue of how to ensure metastability of this state over cosmological time.
• We consider new tree-level operators, the presence of a thermal bath of hidden sector particles, and quantum corrections to the effective potential.
• We find that in the thermal scenario many additional light degrees of freedom are typically required unless coupling constants are somewhat fine-tuned.