DG, Part 6: All The Way With Gauss-Bonnet!

The Gauss-Bonnet Theorem is one of the most unexpected and (to my mind) beautiful results anywhere in mathematics.

( Curvatures )

A-a-and we're done.

Note: "Bonnet" rhymes with "way". Wordplay courtesy of Michael Spivak.

Silly Songs

Apropos of absolutely nothing (except that it's playing on Jukebox): I think the Moody Blues' "Nice to Be Here" is my favorite silly song. (It's in the same general class with, but superior to, Creedence's "Looking Out My Back Door".)