The length scale dependence of viscosity approaching the glass transition in glycerol

Abstract
We measure the viscosity of glycerol by using photon correlation spectroscopy to observe the Brownian motion of small (∼100 nm) polystyrene spheres. By comparing the viscosity measured with different size spheres, we can measure the length scale dependence of the viscosity as the liquid is cooled towards the glass. In contrast to published reports, we observe no spatial dispersion in the viscosity.