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Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.

• CommentRowNumber1.
• CommentAuthorzskoda
• CommentTimeSep 2nd 2011

To add recent surge of activity (by Urs, me etc.) in $n$Lab on symplectic geometry, variational calculus and mechanics I created the entry Lagrange multiplier following mainly Loomis-Strenberg. For convenience, I uploaded the critical 4 pages from their book.

• CommentRowNumber2.
• CommentAuthorTodd_Trimble
• CommentTimeSep 2nd 2011

This was a perfect excuse to add my favorite proof of the spectral theorem for real symmetric $n \times n$ matrices. The usual proofs I’ve seen in textbooks involve the fundamental theorem of algebra, which is a slightly heavy gun for this application. The proof shows that the spectral theorem is a simple application of Lagrange multipliers (and gives more geometric insight; cf. principal curvatures and so forth).

• CommentRowNumber3.
• CommentAuthorzskoda
• CommentTimeSep 2nd 2011

Amazing :)

• CommentRowNumber4.
• CommentAuthorMike Shulman
• CommentTimeSep 3rd 2011

Wow! Nice, Todd.