John Baez's Stuff

What's New?

In week266 of This Week's Finds visit Io, the volcanic moon of Jupiter:

Then read about Pythagoras, the Pythagorean tuning system, the tetractys, and the categorical groups workshop in Barcelona.

You can see the slides for some talks I'm giving:

• Classifying Spaces for Topological 2-Groups, at the Categorical Groups workshop in Barcelona.

• Computation and the Periodic Table, at the conference on Algebraic Topological Methods in Computer Science in Paris.

Phoenix has safely parachuted to the surface of Mars:

This amazing shot was taken by HiRISE, a satellite orbiting Mars that's devoted to taking high-resolution photos. Phoenix didn't really land in a crater; it landed in front of it.

My students have been cranking out papers like mad. They're all in draft form, so if you have comments on them, please let me know:

• Alex Hoffnung, Chris Rogers and I have come out with a draft of our paper Categorified Symplectic Geometry and the Classical String.

• Alex Hoffnung and and I finished a draft of our paper Convenient Categories of Smooth Spaces.

• Mike Stay and I wrote a big review of how category theory serves as a unifying viewpoint in science: Physics, Topology, Logic and Computation: A Rosetta Stone, to appear in Bob Coecke's volume New Structures of Physics.

All the notes for my 2008 course on Hamiltonian mechanics are now available in LaTeX, courtesy of Alex Hoffnung. They still need a lot of polishing...

Check out the rings of Saturn's moon Rhea.

Here's a nice movie of an Einstein ring:

If you're a mathematician or physicist, please contribute an article to EUREKA Science Journal Watch. This is a wiki on science journals, but so far we only have info on math and physics journals. We're trying to make EUREKA into a catalyst for change. So, if there's a journal with especially good or bad policies and prices, tell the world about it here!

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)
• Seminar (tons of course notes)
• Serious Stuff (my actual research)
• Talks (transparencies of my talks, info on forthcoming talks)
• Diary (random thoughts)

• The n-Category Café

For common questions about physics, you can't beat this:

• Frequently Asked Questions in Physics

If reading my stuff makes you want to ask questions, take a look at this.

© 2006 John Baez
baez@math.removethis.ucr.andthis.edu

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