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by autopoiesis 2497 days ago
It sounds like you would be interested in the book / course '7 Sketches in Compositionality' by David Spivak and Brendan Fong, which studies precisely those ideas categorically, with a particular focus on systems that you might broadly call 'computational': http://math.mit.edu/~dspivak/teaching/sp18/

It has been discussed on Hacker News at least a couple of times previously -- fairly recently, even. You might be interested to look at these discussions:

https://news.ycombinator.com/item?id=20376325

https://news.ycombinator.com/item?id=19701767

Edit to add:

You might also be interested to learn that categorical approaches to linguistics typically take as their starting point monoidal categories, in which there are notions of 'parallel' as well as 'sequential' composition. It turns out that the usual categorical semantics for linguistics shares a lot with the categorical semantics for quantum mechanics: roughly, meanings are vectors, like quantum states. You can read more about doing (finite-dimensional) quantum mechanics entirely using string diagrams (the formal diagrammatic calculus of monoidal categories) in the work of Bob Coecke, who also played a large part in originating these approaches to linguistics.

For example, on the quantum side, an excellent book is 'Picturing Quantum Processes' [0]. And on the linguistics side, the paper linked in the article is a good start: https://arxiv.org/abs/1003.4394

[0] Not freely available, but some slides are at https://www.cs.ox.ac.uk/ss2014/programme/Bob.pdf

Edit, again:

There is also of course Bartosz Milewski's book / blog series 'Category Theory for Programmers', which introduces category theory from the perspective of Haskell and C++ programming: https://bartoszmilewski.com/2014/10/28/category-theory-for-p...

But the best introduction to category theory I have read is Leinster's book, 'Basic Category Theory': https://arxiv.org/abs/1612.09375

And as you might have guessed, I do agree with your statement!

1 comments

> It turns out that the usual categorical semantics for linguistics shares a lot with the categorical semantics for quantum mechanics

so?

One other thing that has a lot in common with those two is algebraic data types. Products and sums crop up in all these areas. Maybe it's enough to say that with category theory, we feel like we are revealing the "elementary particles" (or rules) of all of these systems.
Type theory has also been applied to both linguistics and quantum mechanics.

What does it mean that both category theory and type theory have been applied to both linguistics and quantum mechanics?

"categorical semantics for linguistics" gives 0 hits in Google btw.

"categorical semantics for quantum mechanics" gives 5 hits all of which reference the same paper by Bob Coecke titled “Strongly Compact Closed Semantics”, which uses the phrase only once.

I'm showing 1M and 200K Google results for those phrases, respectively.
Those exact phrases? In quotation marks?
No, those result numbers do not include quotation marks. With the quotes I show the same results as you.