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Jun
12
comment is there a property of a category that is preserved by category isomorphism, but not equivalence?
+1 Nice examples too!
Jun
12
comment is there a property of a category that is preserved by category isomorphism, but not equivalence?
+1 Nice examples!
Jun
7
answered English-Italian translations of “sieve” and “sink” in sheaf theory
May
27
comment Category theory for sensorimotor learning?
The word "sensorimotor" in the title, is a technical term or a typo? If it is a typo you might wish to edit it.
May
25
comment How does one show that two functors are *not* isomorphic?
@MarianoSuárez-Alvarez..... This may or may not be easier, but is certainly a different problem, thus not a tautology. Awodey gives an explicit example of this with posets.I realize that my answer is very general, but so appears to be (some of) the OP's questions (title and 3rd paragraph). You and others have covered the specific examples mentioned in the rest of the Op's post. By the way, I do appreciate your smiley, we are all here to help and learn from each other in a relaxed atmosphere :-)
May
25
comment How does one show that two functors are *not* isomorphic?
@MarianoSuárez-Alvarez I was not aware of a comment mentioning invariants. I looked at this question only a few hours ago and I did not see that comment. Please note that I plainly said that this procedure is applicable to anything, as long as you can see the * any things* as objects in a suitable category. The rest of my answer is not a tautology. It is a consequence of the Yoneda lemma. I simply emphasized that: to see whether 2 objects are isomorphic, you can check whether the respective Yoneda embeddings are isomorphic. Cont....
May
25
comment How does one show that two functors are *not* isomorphic?
what is the question in your opinion @MartinBrandenburg ?
May
25
answered How does one show that two functors are *not* isomorphic?
May
21
comment A basic doubt on axiom of foundation of Zermelo-Fraenkel set theory
MarkS. and @AsafKaragila I know, I know, but I was under the impression that the OP thought it was relatively easy to come up with such a set S, so I encouraged him to actually do it.
May
21
answered A basic doubt on axiom of foundation of Zermelo-Fraenkel set theory
May
20
comment Preserving structures
great answer and great examples!
May
20
answered Does every category have a functor?
May
6
comment Existence of not locally small categories
can you link the question/answer that started your doubts?
May
5
comment About the category $\mathrm{Set}(G)$
what algebraic topology book are you using?
May
5
revised How to define topology in terms of subobjects?
edited small typos
May
5
suggested approved edit on How to define topology in terms of subobjects?
May
5
answered Thin categories: up to isomorphism Vs up to equivalance
May
5
revised Thin categories: up to isomorphism Vs up to equivalance
edited catlab -> ncatlab
May
5
suggested approved edit on Thin categories: up to isomorphism Vs up to equivalance
May
5
revised Left adjoint in a functor category
corrected grammar