• Kenny Courser, *Open Systems: A Double Categorical Perspective*, Ph.D. thesis, U. C. Riverside, 2020.

Awesome! Congratulations.

]]>• John Baez and Brendan Fong, A compositional framework for passive linear networks, *Theory and Applications of Categories* **33** (2018), 1158–1222.

The referee took a long time, but they caught some serious errors and also demanded a major restructuring of the paper. We rewrote it using Brendan’s ideas on decorated corelations, and it’s become a much deeper paper, but also shorter.

Brendan is coming by this Sunday—Thanksgiving weekend—and we’ll celebrate the end of a project that started in 2013.

]]>Forcing->Seducing sounds cooler… ;)

]]>• John Baez, Brandon Coya and Franciscus Rebro, Props in network theory.

We illustrate the usefulness of props by giving a new, shorter proof of the ‘black-boxing theorem’ proved here:

• John Baez and Brendan Fong, A compositional framework for passive linear networks. (Blog article here.)

]]>• Jonathan Lorand and Fabrizio Genovese, Hypergraph categories of cospans, The *n*-Category Café, 28 February 2018.

What’s especially interesting to me is that both Jonathan and Fabrizio know some mathematical physics, and they’re part of a group who will be working with me on some problems as part of the Applied Category Theory 2018 school! Brendan and Blake Pollard and I used symplectic geometry and decorated cospans to study the black-boxing of electrical circuits and Markov processes… maybe we should try to go further with that project!

]]>• John Baez and Brendan Fong, A compositional framework for

passive linear networks. (Blog article here.)

or my paper with Blake Pollard on reaction networks:

• John Baez and Blake Pollard, A compositional framework for reaction networks.

will find many of Darbo’s ideas eerily similar.

]]>Brendan was the first to join the project. I wanted him to work on electrical circuits, which are a nice familiar kind of network, a good starting point. But he went much deeper: he developed a general category-theoretic framework for studying networks. We then applied it to electrical circuits, and other things as well.

]]>Brendan was the first to join the project. I wanted him to work on electrical circuits, which are a nice familiar kind of network, a good starting point. But he went much deeper: he developed a general category-theoretic framework for studying networks. We then applied it to electrical circuits, and other things as well.

]]>