Quintessence Saves Higgs Instability

TL;DR

This paper investigates a quintessence-Higgs coupling model, deriving bounds on the coupling parameter that ensure vacuum stability during inflation, and discusses its testability and implications for the Swampland Conjecture.

Contribution

It introduces a coupled quintessence-Higgs model, calculates bounds on the coupling parameter for vacuum stability, and links these bounds to observational prospects and theoretical conjectures.

Findings

Lower bound on coupling parameter $\xi > 0.35$ for stability.

Upper bound on $\xi$ from dark energy observations $\xi \\lesssim 0.6$.

Parameter space can be tested in near future.

Abstract

We study a model where quintessence potential $e^{-\xi\phi}$ coupled to Higgs potential. We calculate the evolution of the quintessence, and track the running of the effective Higgs self-coupling. We find it slightly larger than that of the standard model in the past. Requiring the electroweak vacuum to be absolutely stable in inflationary era, we find a lower bound $\xi> 0.35\pm 0.05$, where the uncertainty is mainly from the measurement of the top quark mass. This lower bound, together with the upper bound from the observation for dark energy $\xi\lesssim0.6$, narrows down the parameter space and makes it possible to test this model in the near future. Interestingly, the bound on $\xi$, if actually shown to be the case by observation, supports the recently proposed Swampland Conjecture.