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At the Topos Institute this summer, a group of folks started talking about thermodynamics and category theory. It probably started because Spencer Breiner and my former student Joe Moeller, both ...

This week in our seminar on Cohomology and Computation we continued discussing the bar construction, and drew some pictures of a classic example ...

Christoph Wockel asks me to forward the following question to the n n-Café: What is a reference for a generalisation of the following canonical cocycle to higher dimensions? Thanks for any hints. My ...

The math-blogosphere is abuzz with interest in the new Math Overflow, a mathematics questions and answers site. Already we at the Café have been helped with the answer to a query on the Fourier ...

A while back Gina asked why computer scientists should be interested in categories. Maybe you categorical computer scientists out there have your own favorite answers to this? I’d be glad to hear them ...

Category Theory and Biology Posted by David Corfield Some of us at the Centre for Reasoning here in Kent are thinking about joining forces with a bioinformatics group. Over the years I’ve caught ...

Finally we get to see James Dolan in action, talking about Geometric Representation Theory! While I’ve been focusing on examples, now we’ll start to see the general principles at work in geometric ...

In the penultimate lecture of last fall’s Geometric Representation Theory seminar, James Dolan lays the last pieces of groundwork for the Fundamental Theorem of Hecke Operators.

I am thinking about cosimplicial objects in the category of generalized smooth algebras as models for the (∞, 1) (\infty,1)-quantities (see there for what I mean) dual to models for ∞ \infty-stacks.

If you missed the earlier parts of this series, you can see polished-up versions on my website: Part 1: integral octonions and the Coxeter group E 10. Also available here on the n -Category Café .

Let’s take a break from all this type theory and ∞ \infty-stuff and do some good old 2-dimensional category theory. Although as usual, I want to convince you that plain old 2-categories aren’t good ...