Almost immediately after getting off the plane at Heathrow, I got some breakfast and some change in the form of metal shapes of constant width. That’s right, all British coins are shapes of constant width. This isn’t remarkable because circles have constant width, and most coins are circles. But the UK has non-circular coins that also have constant width: the 20 and 50 pence pieces are both rounded heptagons, part of a family of shapes of constant width called Reuleaux polygons.
Read the full post at Roots of Unity.
Recent Comments