Hanne Kekkonen
I'm a mathematician interested in visualising topological shapes and
using them to introduce otherwise difficult to grasp mathematical
concepts to the general public. I create shapes from several different
medium and I'm especially interested in (negative) curvature.
This 'hyperbolic football' was created using Phizz origami units,
surrounding a heptagon by seven hexagons resulting in tiling
{6;6;7}. The hyperbolic plane has constant negative curvature and
is too large to lie flat. You can approximate a hyperbolic surface
by surrounding a heptagon (internal angles 128.57°) by seven
hexagons (internal angles 120°). A vertex where two hexagons and
one heptagon meet then sums up to 368.57°, creating a 8.57° excess
compared to 360°, which would create a flat surface.