Gerard Westendorp has a real knack for geometry, and here is his answer. Here is Thurston’s procedure. First draw the lattice of Eisenstein integers in the complex plane: ...

Nov 2, 2024 You can now apply for the 2025 Summer Research Associate program at the Topos Institute! The deadline to apply is January 17, 2025.

Projects range from applied category theory to logic, programming languages, and science, technology, and society. Specific topics for 2025 include, but are not limited to: Computational category ...

And the course feels like it’s mostly converging with any other set theory course, just with the special feature that everything remains resolutely isomorphism-invariant. This week we constructed N ...

Are you interested in using category-theoretic methods to tackle problems in topics like quantum computation, machine learning, numerical analysis or graph theory? Then you might like the Adjoint ...

Thurston’s paper Shapes of polyhedra and triangulations of the sphere is really remarkable. I’m writing about it in my next column for the Notices of the American Mathematical Society. Here’s a draft ...

Sep 27, 2021 Introduction to the weakly globular double categories model of bicategories as part of the adjoint school for Applied Category Theory 2021.

A category theorist might imagine that a chapter with this title would be about constructing colimits, and they’d be half right.

W. P. Thurston, Shapes of polyhedra and triangulations of the sphere. Let me describe one of the key ideas as simply as I can. If you cut out the yellow shape here, you can fold it up along the red ...