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Only defined when digons are spherical lunes?

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According to the MathWorld article, hosohedra are constructed of spherical lunes and have only two vertices. The Wikipedia article omits this information in the introductory paragraph, relegating it to a later paragraph describing the instance of a hosohedron as a spherical tesselation. Are there other possiblities? If not, I suggest incorporating that information into the introduction to improve clarity. andersonpd 19:38, 3 August 2006 (UTC)[reply]

The Coxeter reference also only mentions hosohedrons only in the context of spherical and "unbounded nonorientable" surfaces (pp 12, 68). Apparently, this is the definition, and I can't find any citations of the "degenerate polyhedron" meaning. Page edited to reflect this. Thanks for the petulancy; it's always appreciated. Phildonnia


Multidimensional analogues?

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This text is given:

The 4-dimensional analogue is called a hosochoron (plural: hosochora). For example, {3,3,2} is a tetrahedral hosochoron.

Any references for this?! ALSO, I'd expect {3,3,2} would be a tetrahedral dichoron, parallel to a {3,2} triangular dihedron. Tom Ruen 21:01, 5 October 2006 (UTC)[reply]

Only reference I can find is:
  • [1] - H.S.M. Coxeter's term for a polytope with two vertices. Such are the duals to ditopes.
  • [2] A polytope with two [facets], the dual of a hosotope. (I substituted facet for face in reference)
So I think {p,q,...,2} is a regular ditope (2 {p,q,...} facets), and {2,...,q,p}, the dual, is perhaps a regular hosohedron (2 vertices)?

Since no one else seems to be watching this page I 'corrected the hosotope section best I could, but I don't think the naming is clearly rational - {2,3,3} has a tetrahedral vertex figure at least. I didn't look back who added it - perhaps should just be removed. Tom Ruen 07:57, 29 November 2006 (UTC)[reply]

etymology

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The prefix “hoso-” was invented by H.S.M. Coxeter, and possibly derives from the English “hose”.

Any reason not to presume it's Greek ὅσο– 'as much'? —Tamfang (talk) 03:46, 27 July 2009 (UTC)[reply]

No knowledge from me! Tom Ruen (talk) 04:33, 27 July 2009 (UTC)[reply]

Relation to Special Cases?

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The redirection to here from the trihedron page seems to need some clarification, since this page (for hosohedron) does not include the term trihedron or a definition of the term trihedron. There is some information on MathWorld about the notion of a trihedron, but it is minimal. I hope that someone who knows about trihedra will add a page for them (or a section here...), because I wanted to know more about their groups of symmetries, which apparently are called "trihedral groups". Matt Insall 18:01, 8 July 2017 (UTC) — Preceding unsigned comment added by Espresso-hound (talkcontribs)

Coxeter?

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In the section Etymology it says "The term 'hosohedron' was coined by H.S.M. Coxeter...". But according to Coxeter's Regular Complex Polytopes (1974, ISBN:052120125X) p. 20: "The hosohedron {2,p} (in a slightly distorted form) was named by Vito Caravelli (1724-1800), and the dihedron {p,2} by Felix Klein (1849-1925)." Episcophagus (talk) 09:16, 10 August 2019 (UTC)[reply]

See Vito Caravelli, Archimedis theoremata (1751) p. 152: "Liber tertius: De Hosoedris." -Episcophagus (talk) 09:37, 10 August 2019 (UTC)[reply]
Quite right AFAICT, @Episcophagus: the Schwartzman lemma referenced for the etymology doesn’t even mention HSMC (although I guess he may have ‘popularized’ the term). Any reason we shouldn’t cite Coxeter as above to credit Caravelli? Otherwise, although it would be WP:OR to say his was the first usage, I think per WP:PRIMARY & WP:BLUE we could say merely that it appears in his 1751 work.—Odysseus1479 01:45, 14 June 2021 (UTC)[reply]
@Odysseus1479:. Of course it is Caravelli who should be credited for introducing the term 'hosohedron' - and even HSM Coxeter agrees on this. Episcophagus (talk) 16:07, 14 June 2021 (UTC)[reply]
@Episcophagus:  Done.—Odysseus1479 23:08, 3 July 2021 (UTC)[reply]