Growing spatial correlations of particle displacements in a simulated   liquid on cooling toward the glass transition
  We define a correlation function that quantifies the spatial correlation of single-particle displacements in liquids and amorphous materials. We show for an equilibrium liquid that this function is related to fluctuations in a bulk dynamical variable. We evaluate this function using computer simulations of an equilibrium glass-forming liquid, and show that long range spatial correlations of displacements emerge and grow on cooling toward the mode coupling critical temperature. 
Claudio Donati, Sharon C. Glotzer and Peter H. Poole