Holonomy Blocks
A large-scale interactive exhibit for the Museum of Mathematics (MoMath), New York, made with Henry Segerman. Three CNC-carved wooden surfaces — a sphere (positive curvature), a flat plane (zero curvature), and a pseudosphere (negative curvature) — each carry a metal rook that slides along rails carved into the surface. Moving the rook around a right-angled polygon and returning to the start, visitors discover that the rook has rotated: the angle of rotation is the holonomy, directly encoding the total curvature enclosed. The same rook design works on all three surfaces, making the comparison immediate.
