Phyllotaxis
the spirals are counted, not admired
Concept

Resolution — where it appears

The smallest step an instrument can represent, which sets a floor on every quantity computed from it and can manufacture structure below that floor.

Named by 2 essays across 2 fields — each of them below, with the objects they name alongside it.

00.2000.4000.600-3-2.50-2-1.50-1-0.700offset from the rational, log₁₀ of degreesμ₂300 points600 points1200 points5/13 of a turn · 12 offsets · vertical rules are the half-widthsgenerated from a stated rule, not drawn to look right

A dip belongs to the head

At an exact rational the disorder halves when the head doubles, and the dip around it narrows by a factor of four. So which angles look ordered is set by how many organs were counted, and a head of three hundred cannot tell 138.4615° from 138.48° while a head of twelve hundred tells it from 138.4625°.

tissue · second statistic 139.688°as grown220.313°its mirror060120180organs placed after the cutdivergencerise 0.032 · organs 2 and 3 back removed · counted 3/5generated from a stated rule, not drawn to look right

A period the grid invented

A wrecked stem was reported as settling into a repeating block of three angles — 219.84°, 220.31°, 220.78° — which is the smaller of its two spiral counts and would have confirmed a standing prediction. Those three numbers are three consecutive samples of the azimuth grid. There is no block; there is a constant the grid cannot write down, and the routine that found the block was working perfectly.

wrong · instrument ceiling

Named alongside it

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

ArtefactDivergence angleHonest limitsMeasurementSummary statisticAblationAnnulusAttractorBiasClaim testingDiscretisationDisorder

All concepts