I spent at least 9 hours today thinking about squishing baloon-shaped surfaces into other shapes. This is what a PhD program in math is doing to me.[1]

Having learning as a full-time job is really, really delicious. But tonight when I stopped mathing and engaged the edublogosphere it felt like a relief to read about classrooms, populated by humans. (To my fellow humans: I love the differentiable manifolds but I love you more.) Thanks Jesse Johnson, Dan Goldner, and Kate No Wackness[2] for your continuing dedication to learning (your kids’, yours and ours).

Holy Crap, a Three-Legged Table Can Never Be Wobbly.

This is my favorite thing ever.

[1]The particular thought that was driving me crazy at least from 7pm to 10pm, not that you care, was: if $f:X \rightarrow Y$ is any surjective continuous function between topological spaces that maps open sets to open sets, then I can prove that the inverse image of a compact set is compact. I studied a converse if $X$ and $Y$ happen to be smooth manifolds and $f$ happens to be an injective immersion. But these are very very strong assumptions. How much can they be weakened?

[2]Kate, this is A’s name for you. (An homage to your no bullsh*t approach.)