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Oct 9, 2023 at 17:11 history edited Charles Wang
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Oct 9, 2023 at 17:09 answer added Charles Wang timeline score: 2
Oct 8, 2023 at 9:46 answer added Martin Brandenburg timeline score: 2
Oct 8, 2023 at 7:47 comment added Maxime Ramzi When the source and target are cartesian-monoidal, symmetric monoidal functors and product-preserving functors form equivalent categories
Oct 8, 2023 at 3:46 comment added Qiaochu Yuan (These are a priori different; for a functor $F : C \to D$ to be product-preserving means that the canonical map $F(X \times Y) \to F(X) \times F(Y)$, which exists because of the universal property of the product, is an isomorphism. In particular this is a property of a functor $F$. Whereas being a symmetric monoidal functor only requires some coherent collection of such isomorphisms to exist, not necessarily the canonical one, and is extra structure on a functor $F$ in general. This distinction is probably why Tim asked what symmetric monoidal structures you were taking.)
Oct 8, 2023 at 3:44 comment added Qiaochu Yuan @Charles: FWIW I think it would have been a lot less confusing to talk about the powers of $\mathbb{N}$ as a Lawvere theory (this makes it clear that $\mathbb{N}$, at least, is a model of this theory, which is otherwise not so obvious). It would also perhaps be useful context to note in the text of the question that if $\mathbb{N}$ is replaced with $\{ 0, 1 \}$ the resulting Lawvere theory is the Lawvere theory of Boolean algebras. Also, do you really mean "symmetric monoidal functors" or do you mean product-preserving functors in the usual Lawvere theory way?
Oct 8, 2023 at 0:51 history edited Martin Brandenburg CC BY-SA 4.0
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Oct 4, 2023 at 2:25 comment added Charles Wang I'm only looking at 1 and the infinite countable sets. The 'actual' category is the full subcategory containing 1 and the powers of the natural numbers, but this is identical to the category stated.
Oct 1, 2023 at 20:10 comment added Martin Brandenburg I am confused by the definition. It sounds as if 1 is not countable, but it is. You are considering the category of all countable sets right? Or do you only look at 1 and the infinite ones?
Sep 28, 2023 at 14:34 comment added Charles Wang Yes, I'm taking the Cartesian monoidal structure here.
Sep 28, 2023 at 8:51 history edited YCor CC BY-SA 4.0
removed capitals from title
Sep 28, 2023 at 3:34 comment added Alec Rhea @TimCampion Wouldn’t Cartesian products be the canonical choice?
Sep 28, 2023 at 1:37 comment added Tim Campion Which symmetric monoidal structures are you taking on these categories?
Sep 28, 2023 at 0:45 history asked Charles Wang CC BY-SA 4.0