On mean-field theories of dynamics in supercooled liquids

Marco Baity-Jesi; David R. Reichman

doi:10.1063/1.5115042

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arXiv · 1906.05818

On mean-field theories of dynamics in supercooled liquids

Marco Baity-Jesi·David R. Reichman

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Abstract

We develop a hybrid numerical approach to extract the exact memory function K(t) of a tagged particle in three-dimensional glass-forming liquids. We compare the behavior of the exact memory kernel to two mean-field approaches, namely the standard mode-coupling theory and a recently proposed ansatz for the memory function that forms the basis of a new derivation of the exact form of K(t) for a fluid with short-ranged interactions in infinite dimensions. Each of the mean-field functions qualitatively and quantitatively share traits with the exact K(t), although several important quantitative differences are manifest.

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Marco Baity-Jesi, David R. Reichman. 2019-06-13. On mean-field theories of dynamics in supercooled liquids. https://doi.org/10.1063/1.5115042

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