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Stream: deprecated: our papers

Topic: open systems and double categories

John Baez (Sep 16 2020 at 18:39):

A while ago I blogged about Kenny Courser's thesis:

• Open Systems: A Double Categorical Perspective (Part 1).

Now I've finally continued:

• Open Systems: A Double Categorical Perspective (Part 2).

This time I finally explain all the problems with decorated cospans! A lot of work relying on them is broken. Luckily Kenny's thesis explains how to fix all these problems.

John Baez (Jan 24 2021 at 01:12):

I just wrote a blog article continuing my explanation of Kenny Courser's thesis:

• Open Systems: A Double Categorical Perspective (Part 3).

Last time I explained the problems with Brendan Fong's original decorated cospans - or more precisely, the problems with many attempts to apply them. This time I explain the "new improved" decorated cospans that solve all these problems.