The Nuclear-Matter Response in the Quark String-flip Model

Abstract

Nuclear matter is modeled directly in terms of its constituent quarks. A many-body string-flip potential is used that confines quarks within hadrons, enables the hadrons to separate without generating van der Waals forces, and is symmetric in all quark coordinates. We present variational Monte Carlo results for the ground-state properties of large, three-dimensional systems. A phase transition from nuclear to quark matter is observed which is characterized by a dramatic rearrangement of strings. We report on exact calculations of the dynamic response of many-quark systems in one spatial dimension. At low density and small momentum transfers the response is substantially larger than that of a free Fermi gas of quarks; this suggests that there is a coherent response from all the quarks inside the hadron. This coherence, however, is incomplete, as the response is suppressed relative to that of a free Fermi gas of nucleons due to the internal quark substructure of the hadron.