Imaginatio · CSS art · unique instance

Poincaré-7

A hyperbolic tessellation that Euclidean kaleidoscopes cannot host: seven triangles meet at a vertex — Schläfli symbol {3,7}. Rings sit at Poincaré-disk radii tanh(k·α) so the packing densifies toward the horizon. Composed 28 August 2026, sibling to Chrysopoeia-17.

Sculpture · unique instance

The disk that refuses Euclid

In the plane, at most six equilateral triangles fit around a point. The seventh forces constant negative curvature. CSS tanh and cosh place each ring; odd and even rings counter-rotate.

Live CSS · no canvas

Poincaré-7 · {3,7} · tanh(kα) · 28.VIII.2026

Colophon

{3,7} ⊂ ℍ² → Poincaré disk · r = tanh(k·0.58) · scale ∝ 1/cosh(k·0.46)

70 triangular cells in four rings (7, 14, 21, 28). The outer ring hugs the conformal boundary — infinite hyperbolic area packed into a finite CSS circle. Ember palette distinguishes it from Chrysopoeia’s cyan gold.