John Baez's Stuff

From January 9th to 13th there will be a workshop on Higher Categories and Their Applications, organized by Eugenia Cheng, Peter May and myself. This is part of the Fields Institute program Geometric Applications of Homotopy Theory, organized by Rick Jardine, Gunnar Carlsson and Dan Christensen. You can see the official Fields Institute schedule of this workshop or my own more detailed, more up-to-date schedule.

Blair Smith surfed in to LA bringing presents for all the good boys and girls:

He brought me a typeset version of my Lectures on Classical Mechanics! Check it out! And if you spot typos or other mistakes, please let me know.

What's this?

Take a guess; then look at the September 6th Astronomy Picture of the Day.

This fall the Quantum Gravity Seminar is divided into two parts, on Quantization and Cohomology and Classical vs. Quantum Computation. Both these have blogs to go with them, where we can discuss things! Try it.

Watch Michael Trott's movie of a knotted torus morphing into a sphere - a soccer ball, just for fun. The math behind this involves a smooth homotopy between the identity map and the Weierstrass elliptic function, which is a branched double cover of the sphere by the torus. I explained in week229 how Charles Saunders Peirce used this to make an interesting map of the world.

What's on This Site

This Week's Finds in Mathematical Physics (my column) Fun Stuff (expository writings and other diversions) Nasty Stuff (human rights, economics and other scandals) The Quantum Gravity Seminar (lots of course notes) Serious Stuff (my actual research) Talks (transparencies of my talks, info on forthcoming talks) Diary (random thoughts) Also try my blog at: The n-Category Café

For common questions about physics, you can't beat this: Frequently Asked Questions in Physics I don't maintain this Physics FAQ - Don Koks does, so please send any comments about it to him, not me!

For more on relativity, check out Chris Hillman's stuff: Relativity on the World-Wide Web

If reading my stuff makes you want to ask questions, take a look at this.
If you want to search my website for a particular word or phrase, try this.

The universe is full of magical things, patiently waiting for our wits to grow sharper. - Eden Philpotts