For most people, the word “polyhedron” conjures up an image of a cube, a tetrahedron, or something similar—a solid figure with flat faces. If the polyhedron is regular, each face has the same size and ...

The distinctive three-dimensional shape in Albrecht Dürer’s 1514 engraving Melencolia I has been the subject of innumerous analyses and still no one is sure what it is or what it means. On the ...

Consider what happens when a vertex of one tetrahedron pierces the face of a second tetrahedron to form a new, more complicated polyhedron. In the resulting geometric form, one triangular face has a ...