Timeline for Category with domain/codomain relations
Current License: CC BY-SA 4.0
12 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| May 11, 2022 at 19:40 | vote | accept | Alec Rhea | ||
| May 11, 2022 at 16:15 | answer | added | Reid Barton | timeline score: 5 | |
| Mar 25, 2022 at 16:27 | comment | added | Vladimir Sotirov | One formalization of categories, functors, distributors, and multi-cells between them is as monoids, monoid homomorphisms, bimodules, and bimodule multimorphisms internal to the virtual double category of classes, functions between them, families indexed by pairs, and multicells between them. From this point of view, what you're doing is shifting how a family of classes indexed by a class is implemented: as a function to the class from the disjoint union of the classes, or as an entire relation to the class from the union of the classes (if you drop entire, then you get a protocategory). | |
| Mar 25, 2022 at 11:42 | comment | added | Alec Rhea | @PaulTaylor I have never taken a class in set theory or category theory; I am completely self-taught on both subjects (and have never taken any classes on mathematical foundations) -- the impression you seem to have that I acquired these tastes from some bad undergraduate class on set theory are misguided, I just find set theory to be the 'right' foundation and type theory to be the 'wrong' one for me, but it's just personal preference. I would love to have a discussion with you about these things when you finish vacation, enjoy! | |
| Mar 25, 2022 at 11:12 | comment | added | Paul Taylor | @fosco. sorry I thought I was replying to Alec. Today I am just tying up loose ends before going on holiday. I have deleted my comments and suggest that Alec should delete the question. Maybe when I get back we could all have an off-line discussion. | |
| Mar 25, 2022 at 7:48 | comment | added | fosco | I understand this is not time or place to discuss the matter, but I'd like to hear advices from wise, experienced mathematicians like you. I'm young-ish and still remember the struggle to understand how to distinguish what you call "bureaucratic questions" from "decent projects". I still have no clue. What marks the difference between the two, and more important: is it an objective, measurable property of the question? Or it's all about sociology/fashion? | |
| Mar 24, 2022 at 20:53 | comment | added | fosco | @PaulTaylor what is "the rubbish that undergrads are taught about set theory as alleged foundations"? You can tell me privately (I guess you can easily find my email address on the web)! (The question is genuine, not rethorical!) | |
| Mar 24, 2022 at 8:29 | comment | added | fosco | Some people tend to dislike questions that are in the form "what if, just for the sake of speculation, this happened?". They want "motivation", as if craving for the answer wasn't a motivation in itself. I like(d) the question, and I wonder what a "category internal to Rel" is, whatever interpretation makes it sensible. | |
| Mar 24, 2022 at 7:32 | history | edited | Alec Rhea | CC BY-SA 4.0 |
added 239 characters in body
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| Mar 24, 2022 at 7:27 | history | edited | Alec Rhea | CC BY-SA 4.0 |
added 239 characters in body
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| Mar 24, 2022 at 7:25 | comment | added | Alec Rhea | Would the anonymous downvoter care to share why they dislike the post? | |
| Mar 24, 2022 at 7:19 | history | asked | Alec Rhea | CC BY-SA 4.0 |