Category theory has its roots in algebraic topology. Homology, fundamental groups, homotopy groups are all examples of what functors.
Abstract nonsense in the sense of stepping back and looking at the general properties that these things satisfy and then deriving general theorems based on those properties totally makes sense.
I’m not a category theorist but my impression of category theory is that it’s about seeing the “big picture” of mathematics. The overarching themes that keep popping up all over mathematics and then having something to say about those themes.
The arxiv CT paper is not only gibberish (even to someone who’s not a category theorist) but it has some clear signs that it was written with the help of AI. As theHigherGeometer (npub1d60…mhwm) noted, “E{{“ should be “Eff” for effective topos (not that I actually know what a topos is).
The entire paper looks off. You don’t have to be a specialist to see that there’s something odd about this paper. No legitimate math paper is written this way. The paper really is nonsense and not the good abstract kind. According to arxiv, it has volunteer mathematicians as moderators papers. Papers are occasionally put on hold when moderators need more time to decide. If arxiv has no category theorists, then they should have put the paper on hold and consulted one.
