{"title":"The additive structure of integers with the lower Wythoff sequence","authors":"Mohsen Khani, Afshin Zarei","doi":"10.1007/s00153-022-00846-2","DOIUrl":"10.1007/s00153-022-00846-2","url":null,"abstract":"<div><p>We have provided a model-theoretic proof for the decidability of the additive structure of integers together with the function <i>f</i> mapping <i>x</i> to <span>(lfloor varphi xrfloor )</span> where <span>(varphi )</span> is the golden ratio.\u0000\u0000\u0000\u0000</p></div>","PeriodicalId":48853,"journal":{"name":"Archive for Mathematical Logic","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00153-022-00846-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42102908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On forcing over (L(mathbb {R}))","authors":"Daniel W. Cunningham","doi":"10.1007/s00153-022-00844-4","DOIUrl":"10.1007/s00153-022-00844-4","url":null,"abstract":"<div><p>Given that <span>(L(mathbb {R})models {text {ZF}}+ {text {AD}}+{text {DC}})</span>, we present conditions under which one can generically add new elements to <span>(L(mathbb {R}))</span> and obtain a model of <span>({text {ZF}}+ {text {AD}}+{text {DC}})</span>. This work is motivated by the desire to identify the smallest cardinal <span>(kappa )</span> in <span>(L(mathbb {R}))</span> for which one can generically add a new subset <span>(gsubseteq kappa )</span> to <span>(L(mathbb {R}))</span> such that <span>(L(mathbb {R})(g)models {text {ZF}}+ {text {AD}}+{text {DC}})</span>.</p></div>","PeriodicalId":48853,"journal":{"name":"Archive for Mathematical Logic","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50007506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Wellfoundedness proof with the maximal distinguished set","authors":"Toshiyasu Arai","doi":"10.1007/s00153-022-00840-8","DOIUrl":"10.1007/s00153-022-00840-8","url":null,"abstract":"<div><p>In Arai (An ordinal analysis of a single stable ordinal, submitted) it is shown that an ordinal <span>(sup _{N<omega }psi _{varOmega _{1}}(varepsilon _{varOmega _{{mathbb {S}}+N}+1}))</span> is an upper bound for the proof-theoretic ordinal of a set theory <span>(mathsf {KP}ell ^{r}+(Mprec _{Sigma _{1}}V))</span>. In this paper we show that a second order arithmetic <span>(Sigma ^{1-}_{2}{mathrm {-CA}}+Pi ^{1}_{1}{mathrm {-CA}}_{0})</span> proves the wellfoundedness up to <span>(psi _{varOmega _{1}}(varepsilon _{varOmega _{{mathbb {S}}+N+1}}))</span> for each <i>N</i>. It is easy to interpret <span>(Sigma ^{1-}_{2}{mathrm {-CA}}+Pi ^{1}_{1}{mathrm {-CA}}_{0})</span> in <span>(mathsf {KP}ell ^{r}+(Mprec _{Sigma _{1}}V))</span>.</p></div>","PeriodicalId":48853,"journal":{"name":"Archive for Mathematical Logic","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44664889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Involutive Uninorm Logic with Fixed Point enjoys finite strong standard completeness","authors":"Sándor Jenei","doi":"10.1007/s00153-022-00839-1","DOIUrl":"10.1007/s00153-022-00839-1","url":null,"abstract":"<div><p>An algebraic proof is presented for the finite strong standard completeness of the Involutive Uninorm Logic with Fixed Point (<span>({{mathbf {IUL}}^{fp}})</span>). It may provide a first step towards settling the standard completeness problem for the Involutive Uninorm Logic (<span>({mathbf {IUL}})</span>, posed in G. Metcalfe, F. Montagna. (J Symb Log 72:834–864, 2007)) in an algebraic manner. The result is proved via an embedding theorem which is based on the structural description of the class of odd involutive FL<span>(_e)</span>-chains which have finitely many positive idempotent elements.\u0000</p></div>","PeriodicalId":48853,"journal":{"name":"Archive for Mathematical Logic","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00153-022-00839-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47378283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Svetlana Aleksandrova, Nikolay Bazhenov, Maxim Zubkov
{"title":"Complexity of (Sigma ^0_n)-classifications for definable subsets","authors":"Svetlana Aleksandrova, Nikolay Bazhenov, Maxim Zubkov","doi":"10.1007/s00153-022-00842-6","DOIUrl":"10.1007/s00153-022-00842-6","url":null,"abstract":"<div><p>For a non-zero natural number <i>n</i>, we work with finitary <span>(Sigma ^0_n)</span>-formulas <span>(psi (x))</span> without parameters. We consider computable structures <span>({mathcal {S}})</span> such that the domain of <span>({mathcal {S}})</span> has infinitely many <span>(Sigma ^0_n)</span>-definable subsets. Following Goncharov and Kogabaev, we say that an infinite list of <span>(Sigma ^0_n)</span>-formulas is a <span>(Sigma ^0_n)</span>-<i>classification</i> for <span>({mathcal {S}})</span> if the list enumerates all <span>(Sigma ^0_n)</span>-definable subsets of <span>({mathcal {S}})</span> without repetitions. We show that an arbitrary computable <span>({mathcal {S}})</span> always has a <span>({{mathbf {0}}}^{(n)})</span>-computable <span>(Sigma ^0_n)</span>-classification. On the other hand, we prove that this bound is sharp: we build a computable structure with no <span>({{mathbf {0}}}^{(n-1)})</span>-computable <span>(Sigma ^0_n)</span>-classifications.</p></div>","PeriodicalId":48853,"journal":{"name":"Archive for Mathematical Logic","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50038891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}