## 23 February 2008

From A neighborhood of infinity: What is topology?, attempting to provide some intuition for the standard axioms that define a topology in terms of "observable sets" (which are just open sets, with different intuition attached to them!)

Also, on a totally unrelated note: John Baez has online notes from the course he gave in Fall '03, Winter '04, Spring '04. The winter notes are particularly interesting to me, because they combine combinatorics (which I know well) and a lot of category-theoretic notions that I'm not too familiar with.

unapologetic said...

That year's seminar really is great. And not only does it get some great combinatorics, it uses them to talk about quantum mechanics!

wing said...

I almost thought Joan Baez was giving math lectures!

Isabel Lugo said...

I believe John Baez (the mathematical physicist) and Joan Baez (the singer) are cousins.

unapologetic said...

Indeed they are. I still need to get him to sign a copy of Diamonds & Rust, and her to sign a copy of Gauge Fields, Knots & Gravity