In category theory we have coends and ends. Coends are generalized sum types, so they corresponds to integrals in calculus and use integral notation.
Ends are generalized products. The main reason we don't use such things in calculus is that we can always convert a product into a sum by using a logarithm. Not so in category theory. The closest we get to logarithms is in representable functors.
Bartosz Milewski
npub1gl…xtqzy
2026-09-09 11:39:24 UTC
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