Excitations Are Localized and Relaxation Is Hierarchical in Glass-Forming Liquids

  title={Excitations Are Localized and Relaxation Is Hierarchical in Glass-Forming Liquids},
  author={Aaron S. Keys and Lester O. Hedges and Juan P. Garrahan and Sharon C. Glotzer and David W. Chandler},
  journal={Physical Review X},
Supercooled glass-forming liquids are known to have complex and sluggish macroscopic dynamics. But, what are the atomic motions underlying such dynamics? Researchers from the US and Britain use state-of-the-art molecular-dynamics simulations to ``visualize,'' identify, and characterize the atomic motions. 

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