J. Log. Comput.Pub Date : 2020-07-28DOI: 10.1093/logcom/exaa037
I. Chajda, H. Länger
{"title":"Sublattices and Δ-blocks of orthomodular posets","authors":"I. Chajda, H. Länger","doi":"10.1093/logcom/exaa037","DOIUrl":"https://doi.org/10.1093/logcom/exaa037","url":null,"abstract":"For orthoposets we introduce a binary relation ∆ and a binary operator d(x, y) which are generalizations of the binary relation C and the commutator c(x, y), respectively, known for orthomodular lattices. We characterize orthomodular posets among orthoposets and orthogonal posets. Moreover, we describe connections between the relations ∆ and ↔ and the operator d(x, y). In details we investigate certain orthomodular posets of subsets of a finite set. In particular we describe maximal orthomodular sublattices and Boolean subalgebras of such orthomodular posets. Finally, we study properties of ∆-blocks with respect to Boolean sublattices and distributive subposets they include. AMS Subject Classification: 06A11, 06C15, 03G12","PeriodicalId":398763,"journal":{"name":"J. Log. Comput.","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133128977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Log. Comput.Pub Date : 2020-07-26DOI: 10.1007/978-3-030-93100-1_11
Yanhong A. Liu, S. Stoller
{"title":"Recursive Rules with Aggregation: A Simple Unified Semantics","authors":"Yanhong A. Liu, S. Stoller","doi":"10.1007/978-3-030-93100-1_11","DOIUrl":"https://doi.org/10.1007/978-3-030-93100-1_11","url":null,"abstract":"","PeriodicalId":398763,"journal":{"name":"J. Log. Comput.","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127499081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Log. Comput.Pub Date : 2020-07-23DOI: 10.1093/logcom/exaa033
W. Dvořák, Anna Rapberger, S. Woltran
{"title":"On the different types of collective attacks in abstract argumentation: equivalence results for SETAFs","authors":"W. Dvořák, Anna Rapberger, S. Woltran","doi":"10.1093/logcom/exaa033","DOIUrl":"https://doi.org/10.1093/logcom/exaa033","url":null,"abstract":"Argumentation frameworks with collective attacks are a prominent extension of Dung’s abstract argumentation frameworks, where an attack can be drawn from a set of arguments to another argument. These frameworks are often abbreviated as SETAFs. Although SETAFs have received increasing interest recently, a thorough study on the actual behavior of collective attacks has not been carried out yet. In particular, the richer attack-structure SETAFs provide, can lead to different forms of redundant attacks, i.e., attacks that are subsumed by attacks involving less arguments. Also the notion of strong equivalence, which is fundamental in nonmonotonic formalisms to characterize equivalent replacements, has not been investigated for SETAFs so far. In this paper, we first provide a classification of different types of collective attacks, and analyze for which semantics they can be proven redundant. We do so for eleven well established abstract argumentation semantics. We then study how strong equivalence between SETAFs can be decided with respect to the considered semantics and also consider variants of strong equivalence. Our results show that removing redundant attacks in a suitable way provides direct means to characterize strong equivalence by syntactical equivalence of so-called kernels, thus generalizing well-known results on strong equivalence between Dung AFs.","PeriodicalId":398763,"journal":{"name":"J. Log. Comput.","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132885115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Log. Comput.Pub Date : 2020-07-23DOI: 10.1093/logcom/exaa028
I. Chajda, D. Fazio, Antonio Ledda
{"title":"The generalized orthomodularity property: configurations and pastings","authors":"I. Chajda, D. Fazio, Antonio Ledda","doi":"10.1093/logcom/exaa028","DOIUrl":"https://doi.org/10.1093/logcom/exaa028","url":null,"abstract":"In this paper, we consider a generalization of the notion of orthomodularity for posets to the concept of the generalized orthomodularity property (GO-property) by considering the $LU$-operators. This seemingly mild generalization of orthomodular posets and its order theoretical analysis yield rather strong application to effect algebras and orthomodular structures. Also, for several classes of orthoalgebras, the GO-property yields a completely order-theoretical characterization of the coherence law, and, in turn, of proper orthoalgebras.","PeriodicalId":398763,"journal":{"name":"J. Log. Comput.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129233977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Log. Comput.Pub Date : 2020-07-23DOI: 10.1093/logcom/exaa029
T. Aravanis, P. Peppas, Mary-Anne Williams
{"title":"A study of possible-worlds semantics of relevance-sensitive belief revision","authors":"T. Aravanis, P. Peppas, Mary-Anne Williams","doi":"10.1093/logcom/exaa029","DOIUrl":"https://doi.org/10.1093/logcom/exaa029","url":null,"abstract":"\u0000 Parikh’s relevance-sensitive axiom (P) for belief revision is open to two different interpretations, i.e. the weak and the strong version of (P), both of which are plausible depending on the context. Given that strong (P) has not received the attention it deserves, in this article, an extended examination of it is conducted. In particular, we point out interesting properties of the semantic characterization of the strong version of (P), as well as a vital feature of it that, potentially, results in a significant drop on the resources required for an implementation of a belief-revision system. Lastly, we shed light on the natural connection between global and local revision functions, via their corresponding semantic characterization, hence, a means for constructing global revision functions from local ones, and vice versa, is provided.","PeriodicalId":398763,"journal":{"name":"J. Log. Comput.","volume":"92 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120901568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Log. Comput.Pub Date : 2020-06-09DOI: 10.1093/logcom/exaa072
Tiziano Dalmonte, Björn Lellmann, N. Olivetti, Elaine Pimentel
{"title":"Hypersequent calculi for non-normal modal and deontic logics: Countermodels and optimal complexity","authors":"Tiziano Dalmonte, Björn Lellmann, N. Olivetti, Elaine Pimentel","doi":"10.1093/logcom/exaa072","DOIUrl":"https://doi.org/10.1093/logcom/exaa072","url":null,"abstract":"We present some hypersequent calculi for all systems of the classical cube and their extensions with axioms ${T}$, ${P}$ and ${D}$ and for every $n geq 1$, rule ${RD}_n^+$. The calculi are internal as they only employ the language of the logic, plus additional structural connectives. We show that the calculi are complete with respect to the corresponding axiomatization by a syntactic proof of cut elimination. Then, we define a terminating proof search strategy in the hypersequent calculi and show that it is optimal for coNP-complete logics. Moreover, we show that from every failed proof of a formula or hypersequent it is possible to directly extract a countermodel of it in the bi-neighbourhood semantics of polynomial size for coNP logics, and for regular logics also in the relational semantics. We finish the paper by giving a translation between hypersequent rule applications and derivations in a labelled system for the classical cube.","PeriodicalId":398763,"journal":{"name":"J. Log. Comput.","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126727043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Log. Comput.Pub Date : 2020-06-02DOI: 10.1093/logcom/exaa030
J. Ciuciura
{"title":"Sette's calculus P1 and some hierarchies of paraconsistent systems","authors":"J. Ciuciura","doi":"10.1093/logcom/exaa030","DOIUrl":"https://doi.org/10.1093/logcom/exaa030","url":null,"abstract":"\u0000 The necessary condition for a calculus to be paraconsistent is that its consequence relation is not explosive. This results in rejection of the principle of ex contradictione sequitur quodlibet. In 1973, Sette presented a calculus, denoted as $P^1$, which is paraconsistent only at the atomic level, i.e. $alpha $ and ${sim }alpha $ yield any $beta $ if, and only if the formula $alpha $ is not a propositional variable. The calculus has been viewed as one of the noteworthy paraconsistent calculi since then. The objective of this paper is to propose a new semantics for Sette’s calculus and present some hierarchies of the paraconsistent calculi, which are based on $P^1$. We demonstrate that $P^1$ is sound and complete with respect to the semantics and so are all the calculi under consideration.","PeriodicalId":398763,"journal":{"name":"J. Log. Comput.","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132845101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Log. Comput.Pub Date : 2020-05-30DOI: 10.1093/logcom/exaa080
D. Normann, Sam Sanders
{"title":"The Axiom of Choice in computability theory and Reverse Mathematics with a cameo for the Continuum Hypothesis","authors":"D. Normann, Sam Sanders","doi":"10.1093/logcom/exaa080","DOIUrl":"https://doi.org/10.1093/logcom/exaa080","url":null,"abstract":"The Axiom of Choice (AC for short) is the most (in)famous axiom of the usual foundations of mathematics, ZFC set theory. The (non-)essential use of AC in mathematics has been well-studied and thoroughly classified. Now, fragments of countable AC not provable in ZF have recently been used in Kohlenbach's higher-order Reverse Mathematics to obtain equivalences between closely related compactness and local-global principles. We continue this study and show that NCC, a weak choice principle provable in ZF and much weaker systems, suffices for many of these results. In light of the intimate connection between Reverse Mathematics and computability theory, we also study realisers for NCC, i.e. functionals that produce the choice functions claimed to exist by the latter from the other data. Our hubris of undertaking the hitherto underdeveloped study of the computational properties of (choice functions from) AC leads to interesting results. For instance, using Kleene's S1-S9 computation schemes, we show that various total realisers for NCC compute Kleene's $exists^3$, a functional that gives rise to full second-order arithmetic, and vice versa. By contrast, partial realisers for NCC should be much weaker, but establishing this conjecture remains elusive. By way of catharsis, we show that the Continuum Hypothesis (CH for short) is equivalent to the existence of a countably based partial realiser for NCC. The latter kind of realiser does not compute Kleene's $exists^3$ and is therefore strictly weaker than a total one.","PeriodicalId":398763,"journal":{"name":"J. Log. Comput.","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122218246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Log. Comput.Pub Date : 2020-05-29DOI: 10.1093/LOGCOM/EXAA038
V. Chernov
{"title":"Locally constant constructive functions and connectedness of intervals","authors":"V. Chernov","doi":"10.1093/LOGCOM/EXAA038","DOIUrl":"https://doi.org/10.1093/LOGCOM/EXAA038","url":null,"abstract":"We prove that every locally constant constructive function on an interval is in fact a constant function. This answers a question formulated by Andrej Bauer. As a related result we show that an interval consisting of constructive real numbers is in fact connected, but can be decomposed into the disjoint union of two sequentially closed nonempy sets.","PeriodicalId":398763,"journal":{"name":"J. Log. Comput.","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121802055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Log. Comput.Pub Date : 2020-05-20DOI: 10.1093/LOGCOM/EXAB065
Sergey Slavnov
{"title":"On embedding Lambek calculus into commutative categorial grammars","authors":"Sergey Slavnov","doi":"10.1093/LOGCOM/EXAB065","DOIUrl":"https://doi.org/10.1093/LOGCOM/EXAB065","url":null,"abstract":"Abstract categorial grammars (ACG), as well as some other, closely related systems, are based on the ordinary, commutative implicational linear logic and linear $lambda$-calculus in contrast to the better known \"noncommutative\" Lambek grammars and their variations. ACG seem attractive in many ways, not the least of which is the simplicity of the underlying logic. Yet it is known that ACG and their relatives behave poorly in modeling many natural language phenomena (such as, for example, coordination) compared to \"noncommutative\" formalisms. Therefore different solutions have been proposed in order to enrich ACG with noncommutative constructions. \u0000Tensor grammars of this work are another example of \"commutative\" grammars, based on the classical, rather than intuitionistic linear logic. They can be seen as a surface representation of ACG in the sense that derivations of ACG translate to derivations of tensor grammars and this translation is isomorphic on the level of string languages. An advantage of this representation, as it seems to us, is that the syntax becomes extremely simple and a direct geometric meaning is transparent. \u0000We address the problem of encoding noncommutative operations in our setting. This turns out possible after enriching the system with new unary operators. The resulting system allows representing both ACG and Lambek grammars as conservative fragments, while the formalism remains, as it seems to us, rather simple and intuitive.","PeriodicalId":398763,"journal":{"name":"J. Log. Comput.","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133481134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}