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Configuration-tree Theoretical Calculation of the Mean-Squared Displacement of Particles in Glass Formers

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 نشر من قبل Chi-Hang Lam
 تاريخ النشر 2018
  مجال البحث فيزياء
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We report an analytical evaluation of the mean-squared displacement (MSD) of the particles in glasses based on their coarse grained trajectories. The calculation is conducted by means of a local random configuration-tree theory that was recently proposed by one of us [C.-H. Lam, J. Stat. Mech. textbf{2018}, 023301 (2018)]. Results are compared with the numerical simulations of a lattice glass model, and good quantitative agreement has been obtained over a wide range of temperatures in the entire region of time with virtually no free parameters. To the best of our knowledge, the calculation is the first in its kind.

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