Close to Jamming

  • Glassy behavior starts at \( \phi \approx 0.55 – 0.59 \)

  • Jamming is at \( \phi \approx 0.64 \)

  • What happens if we go really close to jamming?

    • Permanent Caging

    • Floaters

Floaters

Step Distributions

Close to Jamming:

Glassy:

\( \Delta \phi = \phi_J - \phi = -10^{-4} \)

\( \phi = 0.59 \), \( \Delta \phi = -0.05 \)

Floaters

Close to Jamming:

Glassy:

Step Distributions

Close to Jamming:

Glassy:

Peak at \( 10^{-2} \) : Tight Cages

Peak at \( 10^{-1} \) : Caged Floaters

Peak at \( 10^{-1} \) : Caged Particles

Peak at \( 10^{0} \) : Rearrangements

Step Distributions Close to Jamming

Solid: Backbone

Dashed: Floaters

Thin Dotted: Both

Rearrangements

Hypothesis: Micro-rearrangements and rearrangements occur at different values of \( \Delta \phi\), with \( \Delta \phi \) dependent on system size.

Micro-Rearrangements

Back to Glassy Behavior

System Size Dependence of \( \alpha_2 \)

System Size Dependence of \( \alpha_2 \)

Does \(\phi^\star \) increase with \(N\)?