Percolation Model for Slow Dynamics in Glass-Forming Materials

We identify a link between the glass transition and percolation of regions of mobility in configuration space. We find that many hallmarks of glassy dynamics, for example, stretched-exponential response functions and a diverging structural relaxation time, are consequences of the critical properties of mean-field percolation. Specific predictions of the percolation model include the range of possible stretching exponents 1/3 <=beta <= 1 and the functional dependence of the structural relaxation time tau(alpha) and exponent beta on temperature, density, and wave number.