Difference between revisions of "Talk:Indescribable"

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(Strong indescribability)
(Strong indescribability)
 
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: Thank you. Can "strong" stay where it is in the source, or should I remove it? [[User:BartekChom|BartekChom]] ([[User talk:BartekChom|talk]]) 12:20, 14 May 2022 (PDT)
 
: Thank you. Can "strong" stay where it is in the source, or should I remove it? [[User:BartekChom|BartekChom]] ([[User talk:BartekChom|talk]]) 12:20, 14 May 2022 (PDT)
 
:: Since it is verbatim in the source, I don't know whether to remove it, I should ask Julian [[User:C7X|C7X]] ([[User talk:C7X|talk]]) 12:25, 14 May 2022 (PDT)
 
:: Since it is verbatim in the source, I don't know whether to remove it, I should ask Julian [[User:C7X|C7X]] ([[User talk:C7X|talk]]) 12:25, 14 May 2022 (PDT)
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About the "Indescribable on a set" section, should $R(\alpha)$ be replaced with $V_\alpha$? Also were Richter and Aczel correct to define strongly $Q$-indescribable as reflecting every sentence, which sounds like removing the predicate? Richter and Aczel wrote that their strongly $\Pi_2^0$-indescribable cardinals are necessarily inaccessible, which according to Drake ("Removing the predicate" section) is not true when only considering formulae with no free variables. [[User:C7X|C7X]] ([[User talk:C7X|talk]]) 17:41, 4 July 2022 (PDT)

Latest revision as of 17:41, 4 July 2022

Strong indescribability

Thanks for the edit BartekChom! I believe strongly-Q-indescribable is now nonstandard terminology, due to the age of Richter and Aczel's paper some notational choices (including using ω1 to denote the Church-Kleene ordinal) are not commonly used anymore. C7X (talk) 12:09, 14 May 2022 (PDT)

Thank you. Can "strong" stay where it is in the source, or should I remove it? BartekChom (talk) 12:20, 14 May 2022 (PDT)
Since it is verbatim in the source, I don't know whether to remove it, I should ask Julian C7X (talk) 12:25, 14 May 2022 (PDT)

About the "Indescribable on a set" section, should $R(\alpha)$ be replaced with $V_\alpha$? Also were Richter and Aczel correct to define strongly $Q$-indescribable as reflecting every sentence, which sounds like removing the predicate? Richter and Aczel wrote that their strongly $\Pi_2^0$-indescribable cardinals are necessarily inaccessible, which according to Drake ("Removing the predicate" section) is not true when only considering formulae with no free variables. C7X (talk) 17:41, 4 July 2022 (PDT)