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arXiv · 0903.0148

Geometric interpretation of pre-vitrification in hard sphere liquids

Carolina Brito·Matthieu Wyart
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Abstract

We derive a microscopic criterion for the stability of hard sphere configurations, and we show empirically that this criterion is marginally satisfied in the glass. This observation supports a geometric interpretation for the initial rapid rise of viscosity with packing fraction, or pre-vitrification. It also implies that barely stable soft modes characterize the glass structure, whose spatial extension is estimated. We show that both the short-term dynamics and activation processes occur mostly along those soft modes, and we study some implications of these observations. This article synthesizes new and previous results [C. Brito and M. Wyart, Euro. Phys. Letters, {\bf 76}, 149-155, (2006) and C. Brito and M. Wyart, J. Stat. Mech., L08003 (2007) ] in a unified view.

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Carolina Brito, Matthieu Wyart. 2009-06-04. Geometric interpretation of pre-vitrification in hard sphere liquids. https://doi.org/10.1063/1.3157261

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