Daniel Tubbenhauer's Cayley-Dickson Construction of the Octonions

 He's also planning to do a followup on The Freudenthal–Tits magic square.

See also John Baez's Octonions Review.

I was wondering idly whether it is possible to make sense of all this purely in terms of symmetries of graphs of functions, a la Halmos' treatment in the book Measure Theory See Lewis Carroll - Crocodile-Story.

The indistinct hand-written annotation on the limits is possibly connected with the hand-written double-tick marks at the foot of Page 13.

Toby doing Complex Numbers Bob Ross Style:

I saw this while I was on the streets in San Jose, Costa Rica, and it just seemed a bit weird at the time!

Subscribe to Tibees.

Octonions are the thing, apparently. Now even Amazon are selling them:


See also F4 (Symmetry Group) and Regular 4-polytope (24 cell):



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