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I have written some notes on CoEnd Calculus by Fosco Loregian. They are available below.

Notes by Keith Wright on CoEnd Calculus

I have started to read CoEnd Calculus by Fosco Loregian. These are my notes on that, together with old notes which have been revised in light of what I learned from, or figured out while, reading that book. I have read only a small part of the book, and understood only a small part of that.

But since the book is still under construction, there may be an advantage to making these notes available. I have found a few local misprints that could be easily fixed before the text is printed, so I put this document on the web server, and intend to update it from time to time, but make no promises.

Versions 1 through 4 of these notes were written with reference to version 5 of the book. This fifth version has been updated to refer to version 6 of the book.

Here are the fifth revised (2021-Nov-05) notes by Keith Wright
in Portable Document Format (coend-20211105.pdf 400K)

CoEnd Calculus by Fosco Loregian

Here is the book itself (arXiv:1501.02503v6)

Notes by Keith Wright on some work of Eilenberg, Kelly, and Mac Lane

The second section of the above notes consists of extracts from old notes updated to apply to CoEnd Calculus. Since those notes are on decades-old papers by Eilenberg, Kelly, and Mac Lane, there was never any urgency to make them available, but since I have already posted extracts, I now put up a more complete version.

These are notes and commentary on the paper A Generalization of the Functorial Calculus by Samual Eilenberg and G. Max Kelly and some successor papers. (Actually, it is the first part of my notes. The parts on successor papers are in the table of contents, but not included here.)

I was reading some (relatively) recent papers that use Kelly-Mac Lane graphs and reference Kelly and Mac Lane. That paper was relatively easy to get as a PDF file. It references Eilenberg and Kelly, which was more difficult to locate. After a quest and a saga, and some expert help from WPI librarian Judy Fallon, I was able to get a copy from a microfilm in the basement of the library.

Because the paper may be difficult to obtain, I want to write these notes in such detail that if one only wants to understand the ideas, there will be no need to read the original paper. Of course, if you are interested in the history of the subject, there is no substitute for the original.

Here are the notes as of 2020-12-01 by Keith Wright
on the paper by Eilenberg and Kelly
in Portable Document Format (EKMir1.pdf 221K)
This is changed very little from the first version to be made available on the web server. Warning: it gets rough toward the the end; check the work; don't trust; just verify.

(checked 2021-Nov-05)