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tgb comments on Harry Potter and the Methods of Rationality discussion thread, part 21, chapters 91 & 92 - Less Wrong Discussion

4 Post author: NancyLebovitz 04 July 2013 11:49AM

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Comment author: tgb 05 July 2013 09:02:25PM *  2 points [-]

I can't find the particular proofs of Noether theorems that your link refers to. Can you help me find them? I see no instances of the word "muggle" in Spivak's paper - in fact no index at all. Is there a different version of it? Please help, as I would greatly appreciate reading this!

Edit: I see now that the comment was referring to a book by Spivak, and that the linked PDF is only on 'elementary mechanics.'

Comment author: JohnSidles 05 July 2013 11:20:09PM *  2 points [-]

Edit 1: Kudos to "gjm" (see above) for pointing to Spivak's page on Amazon!

Edit 2: Spivak's Hogwarts proof implicitly uses a fundamental theorem in differential geometry that is called Cartan's Magic Formula ... this oblique magical reference is Spivak's joke ... as with many magical formulas, the origins of Cartan's formula are obscure.

Regrettably, tgb, even the redoubtable Google Books does not provide page-images for Spivak's Physics for Mathematicians: Mechanics I. The best advice I can give is to seek this book within a university library system.

Comment author: gjm 05 July 2013 11:40:40PM 1 point [-]

Amazon UK's "look inside" feature has it. I haven't checked Amazon US. Search for "Muggles"; first result (page 576) is the one.