New Uniform Polychora

For general discussion of polyhedra, not necessarily Stella-specific.
Mecejide
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New Uniform Polychora

Post by Mecejide » Thu Oct 01, 2020 12:59 am

Recently, two new uniform polychora were discovered by someone on the Higher Space Forum named “_Geometer”. They both have 360 tetrahedra, 240 tetrahemihexahedra, and 120 triangular prisms of type 1, and 360 triangular prisms of type 2. They differ only in the orientation of the thahs, just like sadixhix and gadixhix. Their acronyms are sidditsphit and gidditsphit. They have the same symmetry as sispatit and gispatit.

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robertw
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Re: New Uniform Polychora

Post by robertw » Thu Oct 01, 2020 3:00 am

Wow, they found new ones?!

I found the discussion you referred to: http://hi.gher.space/forum/viewtopic.php?f=25&t=2486

I'll have to look into it more later.

Can someone send me the vertex figure as a .stel file, and I'll see if I can get it to work.

Thanks.

Mecejide
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Re: New Uniform Polychora

Post by Mecejide » Thu Oct 01, 2020 4:10 am

How do I send them to you?

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robertw
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Re: New Uniform Polychora

Post by robertw » Fri Oct 02, 2020 4:05 am

I received them, so looks like you found a way, or possibly someone else did?

I'm pleased to see they worked straight away, with Stella4D able to generate the polychoron from just the vertex figure.

Interesting that the vertex figures are facetings of the dodecahedron, and surprising that no one had found them before. I wonder how many others remain to be discovered.

I'll be sure to include them in the next release.

Do they have full names? Did Jonathan Bowers give them the sidditsphit and gidditsphit acronyms? And which one's 1850 and which one's 1851? (I'm guessing s is 1850 and g is 1851?). And do we know who _Geometer is so they can be credited for their discovery?

Mecejide
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Re: New Uniform Polychora

Post by Mecejide » Fri Oct 02, 2020 5:41 pm

_Geometer named them, and Bowers decided to keep the names. I’m not sure on the order, and g- might be #1850 because it was discovered first.

I have no idea who _Geometer is.

Since then, Bowers discovered two more uniforms. One was the blend of two sidditsphits (setut), and the other was the blend of two gidditsphits (getut). I’ll try to send you their .stel files, too.

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robertw
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Re: New Uniform Polychora

Post by robertw » Sun Oct 04, 2020 5:09 am

I would expect the small one to be first in order before the great one, but up to Bowers.

I tried blending the mirror images of the sidditsphit vertex figure together, but that didn't work, so maybe the two sidditsphits are blended another way.

Here's what the 3D cross-sections look like taken halfway through the polychora.

For sidditsphit:
Image

For gidditsphit:
Image

_Geometer
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Re: New Uniform Polychora

Post by _Geometer » Sun Oct 04, 2020 9:36 pm

I am _Geometer

ndl
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Re: New Uniform Polychora

Post by ndl » Mon Oct 05, 2020 3:10 am

Can someone post the .stel files on this forum? Just put them in .zip and they will post just fine. Thanks

Mecejide
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Re: New Uniform Polychora

Post by Mecejide » Thu Nov 05, 2020 10:26 pm

Update: 2 more uniforms (pecuexidfap and pecuexdap) were recently found. The attached file contains their verfs plus several scaliforms’ verfs.
Attachments
Pindap_Thing.zip
(32.04 KiB) Downloaded 45 times

ndl
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Re: New Uniform Polychora

Post by ndl » Fri Nov 06, 2020 5:22 pm

Mecejide wrote:
Thu Nov 05, 2020 10:26 pm
Update: 2 more uniforms (pecuexidfap and pecuexdap) were recently found. The attached file contains their verfs plus several scaliforms’ verfs.
Can you post 1850-1853 also? Thanks

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Jabe
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Re: New Uniform Polychora

Post by Jabe » Wed Nov 18, 2020 9:03 am

Here is a zip file containing the 6 new uniforms and several scaliforms and compounds. It also contains the some of the pseudouniforms generated by blending an odho verf with a sishi member. I was able to tell the odho blends weren't truly uniform by viewing cross sections vertex-on from different vertices which sometimes lead to different results at different vertices.
Attachments
Uniform and Scaliforms.zip
(49.95 KiB) Downloaded 34 times
Last edited by Jabe on Wed Nov 18, 2020 9:09 am, edited 1 time in total.
May the Fourth (dimension) be with you.

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Jabe
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Re: New Uniform Polychora

Post by Jabe » Wed Nov 18, 2020 9:08 am

Here are stella files generated by _Geometer of various finds in the pecuexdap regiment, thought you might like these. There's even one with a convex verf.
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Antiprisms.zip
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robertw
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Re: New Uniform Polychora

Post by robertw » Wed Nov 18, 2020 11:41 am

Jabe wrote:
Wed Nov 18, 2020 9:03 am
Here is a zip file containing the 6 new uniforms and several scaliforms and compounds.
Great, thanks. Do they have official numbers? I think it's 1850-Sidditsphit and 1851-Gidditsphit. What about the others?

Damn, looks like the two new ones I found ARE two of the blends you already found, setut and getut. I didn't find them by blending and wasn't expecting blending to increase the symmetry of the vertex figure to tetrahedral, so I thought I'd found something new. If only I'd tried this a few months ago!
I was able to tell the odho blends weren't truly uniform by viewing cross sections vertex-on from different vertices which sometimes lead to different results at different vertices.
Ha, I did try that briefly, but the results looked very similar and very complicated, so I couldn't really spot the difference.

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Jabe
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Re: New Uniform Polychora

Post by Jabe » Wed Nov 18, 2020 1:10 pm

1852 - Setut
1853 - Getut
1854 - Pecuexidfap
1855 - Pecuexdap
May the Fourth (dimension) be with you.

Mecejide
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Re: New Uniform Polychora

Post by Mecejide » Fri Jan 29, 2021 5:09 pm

243 more have just been discovered, bringing the count up to 2098. They are all in the disdi regiment.

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