Refusal — where it appears
Two numbers out of the points
A seed head's divergence angle can be recovered from its spiral counts only to within an interval, because a range of angles gives the same counts. On a stem the counts come with lengths attached, two measurements pin two unknowns, and the lattice comes back to the last digit it was built with.
Which minimum was chosen
The rule takes an argmin, so there are two completely different things noise can do to it: move the answer, or move the question. One of them can change what is chosen and the other cannot, ever — and the difference is exactly zero against one or two placements in a thousand, at amplitudes where every other measurement says the two are identical.
Named alongside it
The objects these essays reach for when they reach for this one.
Divergence angleIdentifiabilityBasinBranch selectionCylinderEnsembleEquilibriumFibonacciInverse problemLocal minimumMeasurementMetastability