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Does a growing static length scale control the glass transition?

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 نشر من قبل Matthieu Wyart
 تاريخ النشر 2017
  مجال البحث فيزياء
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Several theories of the glass transition propose that the structural relaxation time {tau}{alpha} is controlled by a growing static length scale {xi} that is determined by the free energy landscape but not by the local dynamical rules governing its exploration. We argue, based on recent simulations using particle-radius-swap dynamics, that only a modest factor in the increase in {tau}{alpha} on approach to the glass transition may stem from the growth of a static length, with a vastly larger contribution attributable instead to a slowdown of local dynamics. This reinforces arguments that we base on the observed strong coupling of particle diffusion and density fluctuations in real glasses



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