Jamming criticality revealed by removing localized buckling excitations

Area of Science:

• Physics
• Statistical Mechanics
• Materials Science

Background:

• Recent theories provide exact, first-principles descriptions of jamming criticality in infinite dimensions.
• Universal scaling relations predict power-law exponents for interparticle gaps and weak forces near the jamming transition.
• The exponent for weak force distribution has been debated, unlike the constant scaling of interparticle gaps.

Purpose of the Study:

• To resolve the ambiguity surrounding the exponent of weak force distribution in frictionless sphere packings.
• To numerically investigate the critical exponents characterizing jamming criticality.
• To test the dimensional robustness of mean-field marginality predictions.

Main Methods:

• Construction of isostatic jammed packings with high numerical accuracy.
• Introduction of a criterion to distinguish particles causing localized buckling excitations ('bucklers').
• Analysis of interparticle gap and weak force distributions near the jamming transition.

Main Results:

• Numerical simulations confirm nontrivial power-law exponents for weak force distributions.
• A clear distinction was made between 'bucklers' and other particles influencing force distributions.
• The exponent for weak forces was found to be dimensionally robust, consistent with mean-field theory.

Conclusions:

• The study resolves the debate on the weak force exponent in jammed packings.
• Numerical findings support the universal scaling relations predicted by mean-field theory for jamming criticality.
• The dimensional robustness of mean-field marginality and its associated criticality is demonstrated.