# Entropy maximization in the force network ensemble for granular solids.

@article{Tighe2008EntropyMI, title={Entropy maximization in the force network ensemble for granular solids.}, author={Brian P. Tighe and Adrianne R T van Eerd and Thijs J. H. Vlugt}, journal={Physical review letters}, year={2008}, volume={100 23}, pages={ 238001 } }

A long-standing issue in the area of granular media is the tail of the force distribution, in particular, whether this is exponential, Gaussian, or even some other form. Here we resolve the issue for the case of the force network ensemble in two dimensions. We demonstrate that conservation of the total area of a reciprocal tiling, a direct consequence of local force balance, is crucial for predicting the local stress distribution. Maximizing entropy while conserving the tiling area and total…

## 66 Citations

The force network ensemble for granular packings

- Physics
- 2010

For packings of hard but not perfectly rigid particles, the length scales that govern the packing geometry and the contact forces are well separated. This separation of length scales is explored in…

Force balance in canonical ensembles of static granular packings

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We investigate the role of local force balance in the transition from a microcanonical ensemble of static granular packings, characterized by an invariant stress, to a canonical ensemble. Packings in…

Stress fluctuations in granular force networks

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- 2011

The heterogeneous force networks in static granular media are distinguished from other network structures in that they must satisfy constraints of mechanical equilibrium on every vertex/grain. Here…

Force network ensemble for the triangular lattice: a tale of tiles.

- PhysicsChaos
- 2009

Large local stresses obey Gaussian statistics, in sharp contrast to the common belief that exponential force statistics are characteristic for granular materials, and is robust to changes in contact network including disordered networks and finite friction coefficient.

Contact forces distribution for a granular material from a Monte Carlo study on a single grain

- Physics
- 2017

The force network ensemble is one of the most promising statistical descriptions of granular media, with an entropy accounting for all force configurations at mechanical equilibrium consistent with…

Cavity method for force transmission in jammed disordered packings of hard particles.

- PhysicsSoft matter
- 2014

A mean-field theory is developed for jammed disordered packings based on the consideration of the contact network as a random graph where the force transmission becomes a constraint satisfaction problem, and a new signature of jamming is found in the small force behavior.

A master equation for the probability distribution functions of forces in soft particle packings.

- PhysicsSoft matter
- 2015

By numerically determining the transition rates for all changes of contacts and gaps, this work forms a Master equation for the PDFs of forces, where the insight one gets from the Transition rates is striking: the mean change of forces reflects non-affine system responses, while their fluctuations obey uncorrelated Gaussian statistics.

Dynamics of correlated forces in lattice model of granular solids near jamming.

- PhysicsSoft matter
- 2014

The model appears to approach point J at a finite temperature, at which various timescales diverge without an obvious corresponding divergence in the correlation length of some static order parameter, suggesting that this lattice model exhibits a hallmark of a dynamical glass transition.

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