Theory 20/Colloid Science
Sedimentation Structure Is a Ratio
The claim
The structure formed by settling colloids is set by the ratio of Péclet number to volume fraction rather than by either alone.
01The mechanism
Péclet sets how strongly gravity biases the walk while fraction sets crowding; together they determine whether the deposit is ordered, gel-like or compacting.
02Predictions
- P1Structure should map onto the ratio.
- P2Either parameter alone should mispredict.
03Refutation
Structure tracking Péclet alone would remove the fraction term.