Talk:Steffen's polyhedron

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Polyhedra

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Constant volume ?

Can/should we add "[hence] It satisfies the proven bellows conjecture which states that the volume of a flexible polyhedron is invariant under flexing." ? - Rod57 (talk) 10:59, 8 November 2017 (UTC)[reply]

When discovered

Can we say when it was discovered/published ? Optimizing the Steffen flexible polyhedron says 1978 but it would be nice to have a better (non-preprint) source.
Any source by Steffen himself ? - Rod57 (talk) 11:46, 8 November 2017 (UTC)[reply]

... The Above preprint refs "[9] Steffen, K. A symmetric flexible Connelly sphere with only nine vertices. Letter written to Institut des Hautes Études Scientifiques, 1978 (available online at [1] )" [handwritten but not signed or dated?] - Rod57 (talk) 11:57, 8 November 2017 (UTC)[reply]

Constant volume ?

When discovered

Further reading ? - Optimizing it