{"title":"Working with arms: Complexity results on atomic representations of Herbrand models","authors":"G. Gottlob, R. Pichler","doi":"10.1109/LICS.1999.782625","DOIUrl":"https://doi.org/10.1109/LICS.1999.782625","url":null,"abstract":"An Atomic Representation of a Herbrand Model (ARM) is a finite set of (not necessarily ground) atoms over a given Herbrand universe. Each ARM represents a possibly infinite Herbrand interpretation. This concept has emerged independently in different branches of Computer Science as a natural and useful generalization of the concept of finite Herbrand interpretation. It was shown that several recursively decidable problems on finite Herbrand models (or interpretations) remain decidable on ARMs. The following problems are essential when working with ARMs: Deciding the equivalence of two ARMs, deciding subsumption between ARMS, and evaluating clauses over ARMS. These problems were shown to be decidable, but their computational complexity has remained obscure so far. The previously published decision algorithms require exponential space. In spite of this, by developing new decision procedures, we are able to prove that all mentioned problems are coNP-complete.","PeriodicalId":352531,"journal":{"name":"Proceedings. 14th Symposium on Logic in Computer Science (Cat. No. PR00158)","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130594278","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}
{"title":"Full abstraction and universality via realisability","authors":"Michael Marz, Alexander Rohr, T. Streicher","doi":"10.1109/LICS.1999.782612","DOIUrl":"https://doi.org/10.1109/LICS.1999.782612","url":null,"abstract":"We construct fully abstract realisability models of PCF. In particular, we prove a variant of the Longley-Phoa Conjecture by showing that the realisability model over an untyped /spl lambda/-calculus with arithmetic is fully abstract for PCF. Further we consider the extension of our results to a general sequential functional programming language SFPL giving rise to universal realisability models for SFPL.","PeriodicalId":352531,"journal":{"name":"Proceedings. 14th Symposium on Logic in Computer Science (Cat. No. PR00158)","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123455166","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}
{"title":"Non-deterministic games and program analysis: An application to security","authors":"P. Malacaria, C. Hankin","doi":"10.1109/LICS.1999.782639","DOIUrl":"https://doi.org/10.1109/LICS.1999.782639","url":null,"abstract":"We present a unifying framework for using game semantics as a basis for program analysis. Also, we present a case study of the techniques. The unifying framework presents games-based program analysis as an abstract interpretation of an appropriate games category in the category of non-deterministic games. The case study concerns an application to security.","PeriodicalId":352531,"journal":{"name":"Proceedings. 14th Symposium on Logic in Computer Science (Cat. No. PR00158)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121300820","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}
{"title":"Abstract syntax and variable binding","authors":"M. Fiore, G. Plotkin, D. Turi","doi":"10.1109/LICS.1999.782615","DOIUrl":"https://doi.org/10.1109/LICS.1999.782615","url":null,"abstract":"We develop a theory of abstract syntax with variable binding. To every binding signature we associate a category of models consisting of variable sets endowed with compatible algebra and substitution structures. The syntax generated by the signature is the initial model. This gives a notion of initial algebra semantics encompassing the traditional one; besides compositionality, it automatically verifies the semantic substitution lemma.","PeriodicalId":352531,"journal":{"name":"Proceedings. 14th Symposium on Logic in Computer Science (Cat. No. PR00158)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128145096","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}
{"title":"Extensional equality in intensional type theory","authors":"Thorsten Altenkirch","doi":"10.1109/LICS.1999.782636","DOIUrl":"https://doi.org/10.1109/LICS.1999.782636","url":null,"abstract":"We present a new approach to introducing an extensional propositional equality in Intensional Type Theory. Our construction is based on the observation that there is a sound, intensional setoid model in Intensional Type theory with a proof-irrelevant universe of propositions and /spl eta/-rules for /spl Pi/and /spl Sigma/-types. The Type Theory corresponding to this model is decidable, has no irreducible constants and permits large eliminations, which are essential for universes.","PeriodicalId":352531,"journal":{"name":"Proceedings. 14th Symposium on Logic in Computer Science (Cat. No. PR00158)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125755760","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}
{"title":"Logics with aggregate operators","authors":"L. Hella, L. Libkin, Juha Nurmonen, L. Wong","doi":"10.1109/LICS.1999.782583","DOIUrl":"https://doi.org/10.1109/LICS.1999.782583","url":null,"abstract":"We study adding aggregate operators, such as summing up elements of a column of a relation, to logics with counting mechanisms. The primary motivation comes from database applications, where aggregate operators are present in all real life query languages. Unlike other features of query languages, aggregates are not adequately captured by the existing logical formalisms. Consequently, all previous approaches to analyzing the expressive power of aggregation were only capable of producing partial results, depending on the allowed class of aggregate and arithmetic operations. We consider a powerful counting logic, and extend it with the set of all aggregate operators. We show that the resulting logic satisfies analogs of Hanf's and Gaifman's theorems, meaning that it can only express local properties. We consider a database query language that expresses all the standard aggregates found in commercial query languages, and show how it can be translated into the aggregate logic, thereby providing a number of expressivity bounds, that do not depend on a particular class of arithmetic functions, and that subsume all those previously known. We consider a restricted aggregate logic that gives us a tighter capture of database languages, end also use it to show that some questions on expressivity of aggregation cannot be answered without resolving some deep problems in complexity theory.","PeriodicalId":352531,"journal":{"name":"Proceedings. 14th Symposium on Logic in Computer Science (Cat. No. PR00158)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132458810","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}
{"title":"Weak bounded arithmetic, the Diffie-Hellman problem and Constable's Class K","authors":"Jan Johannsen","doi":"10.1109/LICS.1999.782621","DOIUrl":"https://doi.org/10.1109/LICS.1999.782621","url":null,"abstract":"The bounded arithmetic theory C/sub 2//sup 0/, which is closely related to the complexity class DLogTime-uniform TC/sup 0/, is extended by a function symbol and axioms for integer division, which is not known to be in DLogTime-uniform TC/sup 0/. About this extended theory C/sub 2//sup 0/[div], two main results are proved: (1). The Z/sub 1//sup b/-definable functions of C/sub 2//sup 0/[div] are exactly Constable's class K, a function algebra whose precise complexity-theoretic nature is yet to be determined. This also yields the new upper bound K/spl sube/uniform NC/sup 2/. (2). The /spl Delta//sub 1//sup b/-theorems C/sub 2//sup 0/[div] do not have Craig-interpolants of polynomial circuit size, unless the Diffie-Hellman key exchange protocol is insecure.","PeriodicalId":352531,"journal":{"name":"Proceedings. 14th Symposium on Logic in Computer Science (Cat. No. PR00158)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127552365","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}
{"title":"Counting and addition cannot express deterministic transitive closure","authors":"M. Ruhl","doi":"10.1109/LICS.1999.782627","DOIUrl":"https://doi.org/10.1109/LICS.1999.782627","url":null,"abstract":"An important open question in complexity theory is whether the circuit complexity class TC/sup 0/ is (strictly) weaker than LOGSPACE. This paper considers this question from the viewpoint of descriptive complexity theory. TC/sup 0/ can be characterized as the class of queries expressible by the logic FOC(<, +, /spl times/), which is first-order logic augmented by counting quantifiers on ordered structures that have addition and multiplication predicates. We show that in first-order logic with counting quantifiers and only an addition predicate it is not possible to express \"deterministic transitive closure\" on ordered structures. As this is a LOGSPACE-complete problem, this logic therefore fails to capture LOGSPACE. It also directly follows from our proof that in the presence of counting quantifiers, multiplication cannot be expressed in terms of addition and ordering alone.","PeriodicalId":352531,"journal":{"name":"Proceedings. 14th Symposium on Logic in Computer Science (Cat. No. PR00158)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130783420","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}
{"title":"Elementary axioms for categories of classes","authors":"A. Simpson","doi":"10.1109/LICS.1999.782592","DOIUrl":"https://doi.org/10.1109/LICS.1999.782592","url":null,"abstract":"We axiomatize a notion of \"classic structure\" on a regular category, isolating the essential properties of the category of classes together with its full subcategory of sets. Like the axioms for a topos, our axiomatization is very simple, but has powerful consequences. In particular, we show that our axiomatized categories provide a sound and complete class of models for intuitionistic Zermelo-Fraenkel set theory.","PeriodicalId":352531,"journal":{"name":"Proceedings. 14th Symposium on Logic in Computer Science (Cat. No. PR00158)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131676460","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}
{"title":"Pattern matching as cut elimination","authors":"S. Cerrito, D. Kesner","doi":"10.1109/LICS.1999.782596","DOIUrl":"https://doi.org/10.1109/LICS.1999.782596","url":null,"abstract":"We present a typed pattern calculus with explicit pattern matching and explicit substitutions, where both the typing rules and the reduction rules are modeled on the same logical proof system, namely Gentzen sequent calculus for minimal logic. Our calculus is inspired by the Curry-Howard isomorphism, in the sense that types, both for patterns and terms, correspond to propositions, terms correspond to proofs, and term reduction corresponds to sequent proof normalization performed by cut elimination. The calculus enjoys subject reduction, confluence, preservation of strong normalization w.r.t. a system with meta-level substitutions and strong normalization for well-typed terms. As a consequence, it can be seen as an implementation calculus for functional formalisms defined with meta-level operations for pattern matching and substitutions.","PeriodicalId":352531,"journal":{"name":"Proceedings. 14th Symposium on Logic in Computer Science (Cat. No. PR00158)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115023533","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}