Z(3) Metastable Bubbles and Chiral Dynamics Across a Dark-QCD Deconfinement Transition
Jingxu Wu, Chenjia Li, Jie Shi
TL;DR
The paper develops a self-consistent dark-QCD chiral-transition framework that preserves a $Z(3)$ center structure in the Polyakov-loop sector and couples it to a chiral order parameter $σ$, enabling a closed chain from vacuum landscape to metastability, domain-wall physics, and bubble nucleation. It characterizes the homogeneous vacuum structure and identifies a metastability window bounded by a spinodal line, then constructs $Z(3)$ domain walls with chiral backreaction to extract wall thickness and surface tension. The dynamics of metastable decay are connected to thermal nucleation through the thin-wall relations $R_c(T)=2Σ(T)/ΔV(T)$ and $S_3(T)/T = (16π/3) Σ(T)^3 /(T ΔV(T)^2)$, using outputs derived from the same effective potential $V_{eff}(σ,ℓ;T)$ to ensure consistency. This framework provides a reproducible, modular pipeline for extensions to full multi-field bounce calculations and potential dark-sector cosmological applications.
Abstract
We present a self-contained theoretical analysis of a dark-QCD chiral transition in which the Polyakov-loop sector retains an explicit $Z(3)$ structure and couples consistently to the chiral order parameter.Working within a coupled chiral--Polyakov effective theory, we map the homogeneous vacuum landscape and identify a metastability window bounded by spinodal loss of stability.We then construct $Z(3)$ domain-wall solutions including chiral backreaction, extracting temperature-dependent wall profiles and surface tension.Finally, we connect homogeneous metastability and wall microphysics to thermal bubble nucleation by evaluating the critical radius $R_c(T)$ and the nucleation exponent $S_3(T)/T$ in the thin-wall regime, providing a compact set of reproducible diagnostics for the decay of the metastable phase.Our results establish a coherent pipeline from vacuum structure to nonperturbative interfaces and nucleation barriers, suitable for systematic extensions to full multi-field bounce calculations and dark-sector cosmological applications.
