Grand 600-cell

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Short description: Regular star 4-polytope with 600 faces
Grand 600-cell
Ortho solid 015-uniform polychoron 33p-t0.png
Orthogonal projection
Type Regular star 4-polytope
Cells 600 {3,3}
Faces 1200 {3}
Edges 720
Vertices 120
Vertex figure {3,5/2}
Schläfli symbol {3,3,5/2}
Coxeter-Dynkin diagram CDel node 1.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.pngCDel 5.pngCDel rat.pngCDel d2.pngCDel node.png
Symmetry group H4, [3,3,5]
Dual Great grand stellated 120-cell
Properties Regular

In geometry, the grand 600-cell or grand polytetrahedron is a regular star 4-polytope with Schläfli symbol {3, 3, 5/2}. It is one of 10 regular Schläfli-Hess polytopes. It is the only one with 600 cells.

It is one of four regular star 4-polytopes discovered by Ludwig Schläfli. It was named by John Horton Conway, extending the naming system by Arthur Cayley for the Kepler-Poinsot solids.

The grand 600-cell can be seen as the four-dimensional analogue of the great icosahedron (which in turn is analogous to the pentagram); both of these are the only regular n-dimensional star polytopes which are derived by performing stellational operations on the pentagonal polytope which has simplectic faces. It can be constructed analogously to the pentagram, its two-dimensional analogue, via the extension of said (n-1)-D simplex faces of the core nD polytope (tetrahedra for the grand 600-cell, equilateral triangles for the great icosahedron, and line segments for the pentagram) until the figure regains regular faces.

The Grand 600-cell is also dual to the great grand stellated 120-cell, mirroring the great icosahedron's duality with the great stellated dodecahedron (which in turn is also analogous to the pentagram); all of these are the final stellations of the n-dimensional "dodecahedral-type" pentagonal polytope.

Related polytopes

It has the same edge arrangement as the great stellated 120-cell, and grand stellated 120-cell, and same face arrangement as the great icosahedral 120-cell.

Orthographic projections by Coxeter planes
H3 A2 / B3 / D4 A3 / B2
Schläfli-Hess polychoron-wireframe-4.png Grand 600-cell-ortho-6gon.png Grand 600-cell-ortho-4gon.png

See also

  • List of regular polytopes
  • Convex regular 4-polytope
  • Kepler-Poinsot solids - regular star polyhedron
  • Star polygon - regular star polygons

References

External links