If anyone is interested in Applied Category Theory, definitely check out the Topos Institute in Berkeley [1]. They do weekly seminars that they post on youtube and a really intriguing blog. I must say that David Spivak is a treasure to hear speak. 7 Sketches in Compositionality [2] was my introduction into Category Theory (written by Spivak and Brendan Fong, another member of Topos), and it really sold the idea of Category Theory as a field that's not just a mathematical meta-language but also a field that can stand on its own. I recommend it over Mac Lane's CWM if you're not a mathematician.<p>[1] <a href="https://topos.site/" rel="nofollow">https://topos.site/</a>
[2] <a href="https://arxiv.org/abs/1803.05316" rel="nofollow">https://arxiv.org/abs/1803.05316</a>
Anyone interested in category theory might be interested in the brand new book <i>The Joy of Abstraction: An Exploration of Math, Category Theory, and Life</i> by Eugenia Cheng.<p><a href="https://www.amazon.com/Joy-Abstraction-Exploration-Category-Theory/dp/1108477224" rel="nofollow">https://www.amazon.com/Joy-Abstraction-Exploration-Category-...</a><p>Then there's of course the classic introduction <i>Conceptual Mathematics</i> by Lawvere and Schanuel.<p><a href="https://www.amazon.com/Conceptual-Mathematics-First-Introduction-Categories/dp/052171916X" rel="nofollow">https://www.amazon.com/Conceptual-Mathematics-First-Introduc...</a>
"A goal of the ACT community is to bridge the gap between theorists using category-theoretic modeling tools and those who want to use the models to say something useful and true about the world"<p>This is key. Sure category theoretic abstractions are useful as a common language. Lot's of theorems are applicable in many domains.<p>The hard thing is understanding all this stuff and mapping it into your domain.
Has anyone actually seen a real world problem being solved via Category Theory? As in, "in the wild", instead of being mentioned on a website dedicated to Category Theory?<p>To me it seems a lot like the crypto and web 3.0 promises of "soon there will be all of these amazing applications"... and then there aren't any.<p>Also, all of the examples of CT I've seen are applicable only to pure functional languages like Haskell, which seems to limit their practical utility.
Which of the results mentioned in the article are proven by applying some result of category theory to another field, and which are just stated using category theory (with the real mathematical insight lying elsewhere)?