Abstract
Based on a microscopic theory developed recently, a dynamical model of density fluctuations in simple fluids and glasses is proposed and analyzed analytically and numerically. The model exhibits a liquid-glass transition, where the glassy phase is characterized by a zero-frequency pole of the longitudinal and transverse viscosities indicating the systems' stability against stress. This also implies an elastic peak in the density-fluctuation spectrum. Approaching the glass transition the slowing down of density fluctuations is controlled by the increasing longitudinal viscosity, which in turn is coupled via a nonlinear feedback mechanism to the slowly decaying density fluctuations. This causes a divergence of the structural relaxation time at a certain critical coupling constant . At the glass transition density fluctuations decay with a long-time power law with and approaching the transition the viscosity diverges proportional to and , where and , below and above the transition, respectively. The long-time tail "paradox" in dense fluids is briefly discussed.
- Received 5 December 1983
DOI:https://doi.org/10.1103/PhysRevA.29.2765
©1984 American Physical Society