2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/16083We have mapped the physics of polymer melts onto a time-dependent Landau-Ginzburg $|ψ|^4$ field theory using techniques of functional integration. Time in the theory is simply a label for the location of a given monomer along the extent of a flexible chain. With this model, one can show that the limit of infinitesimal concentration of a polymer melt corresponds to a {\em dynamic} critical phenomenon. The transition to the entangled state is also shown to be a critical point. For larger concentrations, when the role of fluctuations is reduced, a mean field approximation is justifiably employed to show the existence of tube-like structures reminiscent of Edwards' model.10 pages, 1 eps figure includedSoft Condensed Mattertext