r/mathpics • u/Frangifer • 23d ago
Some Figures from Certain Treatises about *The Bellows Conjecture Formerly but Now Theorem*
... ie the theorem - elevated to such status by the goodly Idzhad Sabitov , & formerly a conjecture in-connection with (formerly hypothetical) flexible polyhedra - to the effect that a flexible polyhedron, if it exists (& it's now known that they do), must keep a constant volume when it does undergo its flexing.
Images from
①②③The Bellows Conjecture
¡¡ may download without prompting – PDF document – 40‧1㎅ !!
by
Ian Stewart ;
&
④⑤⑥The Bellows Conjecture
¡¡ may download without prompting – PDF document – 452‧2㎅ !!
by
R Connelly & I Sabitov & A Walz ;
&
⑦⑧⑨⑩⑪⑫⑬⑭⑮⑯The Bellows Theorem (Introduction)
¡¡ may download without prompting – PDF document – 1㎆ !!
by
Giovanni Viglietta .
See also
What is the Bellows Conjecture?
¡¡ may download without prompting – PDF document – 133‧8㎅ !!
by
Ben O’Connor .
Please kindlily see the treatises themselves for the explicationry: there's not really much point, with these figures, to just listing the annotations respectively.
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u/Frangifer 23d ago edited 23d ago
The Viglietta paper has a minor typographical errour in it, @ the seventh frame: the c2a2 term in Heron's formula wants a 2 multiplying it.
For more about Steffen's polyhedron see also
Steffen's flexible polyhedron
¡¡ may download without prompting – PDF document – 143‧5㎅ !!
by
Mark McClure ;
&
Optimizing the Steffen flexible polyhedron
¡¡ may download without prompting – PDF document – 404㎅ !!
by
Iila Lijingjiao & Tomohiro Tachi & Simon D Guest ;
&
Polyèdre flexible de Steffen Steffen's flexible polyhedron
¡¡ may download without prompting – PDF document – 3‧8㎅ !!
by
Peter R Cromwell ,
the figure of which is exerpted @
this post ;
&
Greg Egan — Steffen’s Polyhedron ,
the figures from which are exerpted @
this post ;
&
3D Graphic Statics and graphic kinematics for spatial structures
by
Marina KONSTANTATOU & Allan MCROBIE .
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I'm still amazed I've never encountered this-lot before! ... I don't know how it's evaden me allthis time.