2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/135727We use a confocal microscope to examine the motion of individual particles in a dense colloidal suspension. Close to the glass transition, particle motion is strongly spatially correlated. The correlations decay exponentially with particle separation, yielding a dynamic length scale of O(2-3 sigma) (in terms of particle diameter sigma). This length scale grows modestly as the glass transition is approached. Further, the correlated motion exhibits a strong spatial dependence on the pair correlation function g(r). Motion within glassy samples is weakly correlated, but with a larger spatial scale for this correlation.Submitted to J Phys: Cond Mat; for Workshop on Nonequilibrium Phenomena in Glasses (Pisa, September 2006)Disordered Systems and Neural NetworksSoft Condensed Mattertext