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Mar 6, 2023 at 10:26 comment added MikeTeX @Daniele tempieri. Isn't something missing in your condition: the fact that the sets $A_n$ are pairwise disjoint does not imply what it is supposed, unless the whole space has finite measure. For example, if we take $\mathbf R_+$ and the $A_n = [n, n+1[$, then these sets are pairwise disjoint but their Lebesgue measure is equal to 1.
Dec 31, 2021 at 17:15 history edited Daniele Tampieri CC BY-SA 4.0
Added direct link to Cody's answer as per suggestion of Spice (see comments)
Dec 31, 2021 at 17:14 comment added Daniele Tampieri @LSpice, thanks. I'll put the ink in the answer.
Dec 31, 2021 at 17:12 comment added LSpice The answer of @coudy referenced here.
Dec 31, 2021 at 17:07 history edited Daniele Tampieri CC BY-SA 4.0
Minor addition (hyperlinked MR and Zbl reviews)
Oct 23, 2021 at 9:15 comment added dohmatob @DanieleTampieri Thanks for the reply, and more broadly, for Cafiero's theorem.
Oct 22, 2021 at 12:27 comment added Daniele Tampieri @dohmatob no: we are really taking the full limit. The condition means that for any family $\{A_n\}_n$ such that the set theoretic limit is the empty set $\emptyset$, the numerical set function $\phi$ goes likewise to $0$ (you surely noticed that $\Cap_{m\ge j\ge n} A_j=\emptyset$ for all $m$). (P.S. I apologize for my later in answer to your comment, and good luck for your researches).
Oct 21, 2021 at 14:29 comment added dohmatob @DanieleTampieri I'm struggling to get my head around the condition $\lim_n \phi(A_n)=0$ for all disjoint $(A_n)_n$, or did you mean $\liminf_n \phi(A_n)$ ?
Jan 15, 2020 at 18:46 history edited Daniele Tampieri CC BY-SA 4.0
Typo in page numbering
Jan 15, 2020 at 18:41 comment added Daniele Tampieri Hi @mathworker21. It is a clarification, perhaps a little pedantic: the definition of uniformly exhaustive I reported from [4] (Definition 1.1, p. 110) refers a simple set $H$, while in Cafiero's theorem we have a net $(f_n\cdot\mu_n)_{n\ge1} which is a particular kind of family. I pointed out that the definition includes that case, since a net is a special case of a (set theoretical) family and each set is a family with itself taken as the index (Halmos docet). Finally, apologies for the later in my answer to your comment: I am very busy now.
Jan 14, 2020 at 13:59 comment added mathworker21 what does "(and thus possibly a family)" mean?
Apr 3, 2018 at 9:56 history edited j.c. CC BY-SA 3.0
minor grammar fixes
Apr 2, 2018 at 19:17 history edited Daniele Tampieri CC BY-SA 3.0
Stated where I learned it.
S Apr 2, 2018 at 19:00 history answered Daniele Tampieri CC BY-SA 3.0
S Apr 2, 2018 at 19:00 history made wiki Post Made Community Wiki by Daniele Tampieri