Cosmochoron (EntityTopic, 12)

From Hi.gher. Space

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Each dodecahedron in its [[net]] lies on a ring of ten dodecahedra along a [[great circle]] of the [[glome]]. There are four dodecahedra on such a ring between any dodecahedron and its antipodal dodecahedron.
Each dodecahedron in its [[net]] lies on a ring of ten dodecahedra along a [[great circle]] of the [[glome]]. There are four dodecahedra on such a ring between any dodecahedron and its antipodal dodecahedron.
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== Geometry ==
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== Equations ==
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=== Equations ===
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*The [[hypervolume]]s of a cosmochoron with side length ''l'' are given by:
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*Variables:
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<blockquote>''l'' ⇒ length of the edges of the hecatonicosachoron</blockquote>
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*All points (''x'', ''y'', ''z'', ''w'') that lie on the [[surcell]] of a hecatonicosachoron will satisfy the following equation:
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<blockquote>''Unknown''</blockquote>
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*The [[hypervolume]]s of a hecatonicosachoron are given by:
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<blockquote>total edge length = 1200''l''<br>
<blockquote>total edge length = 1200''l''<br>
total surface area = 180''l''<sup>2</sup>sqrt(25+10sqrt(5))<br>
total surface area = 180''l''<sup>2</sup>sqrt(25+10sqrt(5))<br>
surcell volume = 300''l''<sup>3</sup>(tan(3π10<sup>-1</sup>))<sup>2</sup>(tan(sin<sup>-1</sup>(2sin(π5<sup>-1</sup>))<sup>-1</sup>))<br>
surcell volume = 300''l''<sup>3</sup>(tan(3π10<sup>-1</sup>))<sup>2</sup>(tan(sin<sup>-1</sup>(2sin(π5<sup>-1</sup>))<sup>-1</sup>))<br>
bulk = ''Unknown''</blockquote>
bulk = ''Unknown''</blockquote>
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*The [[realmic]] [[cross-section]]s (''n'') of a hecatonicosachoron are:
 
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<blockquote>''Unknown''</blockquote>
 
== Projection ==
== Projection ==

Revision as of 18:37, 12 March 2011

The cosmochoron, also known as the hecatonicosachoron and the 120-cell, is a 4D polytope bounded by 120 dodecahedra. It is the highest dimensional analog of the pentagon and the dodecahedron.

Each dodecahedron in its net lies on a ring of ten dodecahedra along a great circle of the glome. There are four dodecahedra on such a ring between any dodecahedron and its antipodal dodecahedron.

Equations

  • The hypervolumes of a cosmochoron with side length l are given by:
total edge length = 1200l
total surface area = 180l2sqrt(25+10sqrt(5))
surcell volume = 300l3(tan(3π10-1))2(tan(sin-1(2sin(π5-1))-1))
bulk = Unknown

Projection

ExPar: [#img] is obsolete, use [#embed] instead ExPar: [#img] is obsolete, use [#embed] instead

Here are two perspective projections of the hecatonicosachoron into 3D. The highlighted center cell is closest to the 4D viewpoint. It is surrounded by 12 dodecahedra in a second layer. The right-hand image also shows the third layer of 32 dodecahedra. After this is a fourth layer of 30 dodecahedra lying on the spherical "equator", followed by three more layers mirroring the three layers seen here (not seen here, because they lie on the 4D "back" of the shape).

Note that only the projection is rotating; the 4D shape itself is not.


Notable Tetrashapes
Regular: pyrochoronaerochorongeochoronxylochoronhydrochoroncosmochoron
Powertopes: triangular octagoltriatesquare octagoltriatehexagonal octagoltriateoctagonal octagoltriate
Circular: glomecubinderduocylinderspherindersphonecylindronediconeconinder
Torii: tigertorispherespheritorustorinderditorus