Shaken, not stirred: why gravel packs better than bricks

Anita Mehta; J. M. Luck

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arXiv · cond-mat/0311500

Shaken, not stirred: why gravel packs better than bricks

Anita Mehta·J. M. Luck

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Abstract

We explore the effect of shape -- jagged vs. regular -- in the jamming limit of very gently shaken packings. Our measure of shape $\eps$ is the void space occupied by a disordered grain; we show that depending on its number-theoretic nature, two generic behaviours are obtained. Thus, regularly shaped grains (rational $\eps$) have ground states of perfect packing, which are irretrievably lost under zero-temperature shaking; the reverse is the case for jagged grains (irrational $\eps$), where the ground state is only optimally packed, but entirely retrievable. At low temperatures, we find intermittency at the surface, which has recently been seen experimentally.

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Anita Mehta, J. M. Luck. 2003-11-21. Shaken, not stirred: why gravel packs better than bricks. https://arxiv.org/abs/cond-mat/0311500

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