Gear Cube involve either half turns or a full rotation. It has six stationary centers, each with a different color, that always stay opposite from another specific center. White is always opposite of yellow. Blue is always opposite of green. Red is always opposite of purple. Each center determines what color that side will be. The centers are exactly based on the original Rubik's Cube. They are connected by a three dimensional cross with screws and springs allowing for less tension. Many cube solvers use the same notation when completing a cube, whether they are working on the original Rubik's Cube, the
Cube a "measure polytope". There are analogues of the cube in lower dimensions too: a point in dimension 0, a segment in one dimension and a square in two dimensions. The quotient of the cube by the antipodal map yields a projective polyhedron, the hemicube. If the original cube has edge length 1, its dual polyhedron (an octahedron) has edge length formula_5. The cube is a special case in various classes of general polyhedra: The vertices of a cube can be grouped into two groups of four, each forming a regular tetrahedron; more generally this is referred to as a demicube.