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Category Archives: Polyhedra
Mr Spock complexes (after Aitchison)
The recent passing of Leonard Nimoy prompts me to recall a lesserknown connection between the great man and the theory of (cusped) hyperbolic 3manifolds, observed by my friend and former mentor Iain Aitchison. In particular, I am moved to give a brief presentation … Continue reading
Cube complexes, Reidemeister 3, zonohedra and the missing 8th region
There is an old puzzle which starts by asking: what is the next number in the sequence 1,2,4,? We are supposed to recognize the start of the sequence and answer that the next number is surely 8, because the first … Continue reading
Zonohedra and the SylvesterGallai theorem
When I was in Melbourne recently, I spent some time browsing through a copy of “Twelve Geometric Essays” by Harold Coxeter in the (small) library at AMSI. One of these essays was entitled “The classification of zonohedra by means of … Continue reading
Posted in Polyhedra, Projective geometry
Tagged Coxeter, projective plane, SylvesterGallai theorem, zonohedra
4 Comments