2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/18695We study the stability of the glassy equilibrium state of a directed polymer in random media against weak perturbations including the intriguing problem of temperature-chaos. The statistical correlation of two real replica systems under perturbations, such as small difference of temperature, is studied using the mapping to a quantum problem of interacting bosons. Explicit replica symmetry breaking takes place being induced by the infinitesimally weak perturbations in the $n \to 0$ limit followed by the thermodynamic limit which leads to complete decorrelation of the two real replicas. The overlap lengths anticipated by phenomenological scaling arguments are retrieved as a correlation length associated with this explicit replica symmetry breaking.5 pagesDisordered Systems and Neural NetworksStatistical MechanicsFragility of the glassy state of a directed polymer in random media: a replica approachtext