Re: [math-fun] Puzzle: Skew planes in 4-space?

Hmm. EGA makes me think of Grothendieck. see: http://en.wikipedia.org/wiki/%C3%89l%C3%A9ments_de_g%C3%A9om%C3%A9trie_alg%C... On Tue, Mar 22, 2011 at 6:26 PM, Fred lunnon <fred.lunnon@gmail.com> wrote:

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The appropriate algebra is Cl(m-1,0,1), with vectors representing (reflections in) hyperplanes: it's time this had a name, and I propose calling it "EGA" in future.

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