ELI5: Explain Like I'm 5

Cross-polytope

A cross-polytope is a special shape that looks like a bunch of squares or triangles glued together in a symmetrical way. Think of it like a bunch of popsicle sticks or toothpicks arranged in a star shape, with the points of the star sticking out.

In math, we call each of the sticks in the cross-polytope a "vertex", and the lines between the vertices "edges". By connecting the edges, we can create different shapes - for example, a 2D cross-polytope is a square, and a 3D cross-polytope is a 4-sided pyramid.

Cross-polytopes are special because each of their vertices is equidistant from all of its neighbors. This means that if you were standing at one vertex and looked out at all the others, they would all look the same distance away - like a bunch of dots on a circle. This property makes cross-polytopes useful in certain mathematical applications, like optimization problems and geometry proofs.
Related topics others have asked about: