Citation

Hagh VF, Corwin EI, Stephenson K, Thorpe MF. Soft Matter 2019; 15(15): 3076-3084.

Affiliation

Department of Physics, Arizona State University, Tempe, AZ 85287-1504, USA. varda.faghirhagh@asu.edu and Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Rd, Oxford OX1 3NP, England, UK.

Copyright

(Copyright © 2019, Royal Society of Chemistry)

DOI

10.1039/c8sm01768a

PMID

30919849

Abstract

Jamming occurs when objects like grains are packed tightly together (e.g. grain silos). It is highly cooperative and can lead to phenomena like earthquakes, traffic jams, etc. In this paper we point out the paramount importance of the underlying contact network for jammed systems; the network must have one contact in excess of isostaticity and a finite bulk modulus. Isostatic means that the number of degrees of freedom is exactly balanced by the number of constraints. This defines a large class of networks that can be constructed without the necessity of packing particles together compressively (either in the lab or computationally). One such construction, which we explore here, involves setting up the Delaunay triangulation of a Poisson disk sampling and then removing edges to maximize the bulk modulus until the isostatic plus one edge is reached. This construction works in any dimensions and here we give results in 2D where we also show how such networks can be transformed into disk packs.

Language: en