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arXiv · 2311.14460

Solid-that-flows picture of glass-forming liquids

Jeppe C. Dyre
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Abstract

This perspective article reviews arguments that glass-forming liquids are different from those of standard liquid-state theory, which typically have a viscosity in the mPa$\cdot$s range and relaxation times of order picoseconds. These numbers grow dramatically and become $10^{12}-10^{15}$ times larger for liquids cooled toward the glass transition. This translates into a qualitative difference, and below the ``solidity length'' which is of order one micron at the glass transition, a glass-forming liquid behaves much like a solid. Recent numerical evidence for the solidity of ultraviscous liquids is reviewed, and experimental consequences are discussed in relation to dynamic heterogeneity, frequency-dependent linear-response functions, and the temperature dependence of the average relaxation time.

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Jeppe C. Dyre. 2023-11-24. Solid-that-flows picture of glass-forming liquids. https://doi.org/10.1021/acs.jpclett.3c03308

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