Phyllotaxis
the spirals are counted, not admired
Concept

Untested claim — where it appears

2 essays name this object, across one field. What follows is each of them, and the objects they name alongside it.
00.50011.50-0.25000.2500.5000.750falloff exponent, log₁₀scatter, log₁₀ degrees00.50011.50-0.25000.2500.5000.750falloff exponent, log₁₀scatter, log₁₀ degreesno latticethe same lattice, whatever pevery runsome runsno runneighbourhood 12/√h · 4 runs per exponenta lattice from p ≈ 1.25 upward

The exponent that barely matters

A code comment on this site claimed since its foundation phase that the repulsion's falloff exponent hardly changes the answer. It could not be tested, because the function that would have taken it never passed one down. Tested at last, it is true on a disc — by three and a half degrees across a sixteenfold range — and on a stem it decides whether there is a pattern at all.

emergence · falloff exponent 00.2500.5000.7501012345distance from the candidate, in local spacingsweight the interaction is multiplied byhalf weightweight = f(d / 3√h)window runs to 4 widths

A neighbourhood is a hypothesis

Every simulation of this kind stops summing somewhere. The previous phase found that where it stops decides what pattern comes out — so the stopping place is not a detail of the program but a claim about how far a primordium's influence reaches, and it should be written down as one.

emergence · interaction range

Named alongside it

The objects these essays reach for when they reach for this one.

MeristemThe placement ruleRepulsionRiseArtefactBranchCut offCylinderDiscretisationDivergence angleEnsembleThe range of the interaction

All concepts