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Rectified 8-cell

Rectified 8-cell, Schlegel diagram, Centered on cuboctahedron
tetrahedral cells shown

In geometry, the rectified tesseract, or rectified 8-cell is a uniform polychoron (4-dimensional polytope) bounded by 24 cells: 8 cuboctahedra, and 16 tetrahedra.

It has two uniform constructions, as a rectified 8-cell t1{4,3,3} and a cantellated demitesseract, t0,2{31,1,1}, the second alternating with two types of tetrahedral cells.


Construction

The rectified tesseract may be constructed from the tesseract by truncating its vertices at the midpoints of its edges.

The Cartesian coordinates of the vertices of the rectified tesseract with edge length 2 is given by all permutations of:


Images


Projections

In the cuboctahedron-first parallel projection of the rectified tesseract into 3-dimensional space, the image has the following layout:

* The projection envelope is a cube.
* A cuboctahedron is inscribed in this cube, with its vertices lying at the midpoint of the cube's edges. The cuboctahedron is the image of two of the cuboctahedral cells.
* The remaining 6 cuboctahedral cells are projected to the square faces of the cube.
* The 8 tetrahedral volumes lying at the triangular faces of the central cuboctahedron are the images of the 16 tetrahedral cells, two cells to each image.


Alternative names

* Rit (Jonathan Bowers: for rectified tesseract)
* Ambotesseract (Neil Sloane & John Horton Conway)
* Rectified tesseract (Norman W. Johnson)
* Rectified 4-hypercube
* Rectified 8-cell
* Rectified octachoron
* Rectified 4-measure polytope
* Rectified 4-regular orthotope
* Runcic tesseract (Norman W. Johnson)
* Runcic 4-hypercube
* Runcic 8-cell
* Runcic octachoron
* Runcic 4-measure polytope
* Runcic 4-regular orthotope


See also

* Tesseract
* Uniform polychoron


Related uniform polytopes

Name tesseract rectified
tesseract
truncated
tesseract
cantellated
tesseract
runcinated
tesseract
bitruncated
tesseract
cantitruncated
tesseract
runcitruncated
tesseract
omnitruncated
tesseract
Coxeter-Dynkin
diagram
Schläfli
symbol
Schlegel
diagram
 
Name 16-cell rectified
16-cell
truncated
16-cell
cantellated
16-cell
runcinated
16-cell
bitruncated
16-cell
cantitruncated
16-cell
runcitruncated
16-cell
omnitruncated
16-cell
Coxeter-Dynkin
diagram
Schläfli
symbol
Schlegel
diagram

Images: Robert Webb's Great Stella software

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