How gluon confinement hides inside BRST symmetry in Yang-Mills theory

The paper constructs a cohomologically trivial quartet of fields in SU(3) Yang-Mills theory in Landau gauge — meaning no physical degrees of freedom are added in the standard vacuum. Choosing a Cartan-oriented background compatible with the equations of motion, the extended theory generates a mass matrix that reproduces the complex-pole propagator structure associated with confined gluons in earlier replica models, but without explicit symmetry breaking. A key result is that despite the complex poles in elementary propagators, a particular composite bilinear retains a Källén–Lehmann spectral representation with a real positive threshold, providing a BRST-consistent framework for renormalizability and confinement-related observables.