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COMPUTER SCIENCE (1148 journals)                  1 2 3 4 5 6 | Last

Showing 1 - 200 of 872 Journals sorted alphabetically
3D Printing and Additive Manufacturing     Full-text available via subscription   (Followers: 11)
Abakós     Open Access   (Followers: 3)
Academy of Information and Management Sciences Journal     Full-text available via subscription   (Followers: 67)
ACM Computing Surveys     Hybrid Journal   (Followers: 23)
ACM Journal on Computing and Cultural Heritage     Hybrid Journal   (Followers: 8)
ACM Journal on Emerging Technologies in Computing Systems     Hybrid Journal   (Followers: 13)
ACM Transactions on Accessible Computing (TACCESS)     Hybrid Journal   (Followers: 4)
ACM Transactions on Algorithms (TALG)     Hybrid Journal   (Followers: 16)
ACM Transactions on Applied Perception (TAP)     Hybrid Journal   (Followers: 6)
ACM Transactions on Architecture and Code Optimization (TACO)     Hybrid Journal   (Followers: 9)
ACM Transactions on Autonomous and Adaptive Systems (TAAS)     Hybrid Journal   (Followers: 7)
ACM Transactions on Computation Theory (TOCT)     Hybrid Journal   (Followers: 11)
ACM Transactions on Computational Logic (TOCL)     Hybrid Journal   (Followers: 4)
ACM Transactions on Computer Systems (TOCS)     Hybrid Journal   (Followers: 18)
ACM Transactions on Computer-Human Interaction     Hybrid Journal   (Followers: 12)
ACM Transactions on Computing Education (TOCE)     Hybrid Journal   (Followers: 3)
ACM Transactions on Design Automation of Electronic Systems (TODAES)     Hybrid Journal   (Followers: 1)
ACM Transactions on Economics and Computation     Hybrid Journal  
ACM Transactions on Embedded Computing Systems (TECS)     Hybrid Journal   (Followers: 4)
ACM Transactions on Information Systems (TOIS)     Hybrid Journal   (Followers: 20)
ACM Transactions on Intelligent Systems and Technology (TIST)     Hybrid Journal   (Followers: 9)
ACM Transactions on Interactive Intelligent Systems (TiiS)     Hybrid Journal   (Followers: 4)
ACM Transactions on Multimedia Computing, Communications, and Applications (TOMCCAP)     Hybrid Journal   (Followers: 10)
ACM Transactions on Reconfigurable Technology and Systems (TRETS)     Hybrid Journal   (Followers: 7)
ACM Transactions on Sensor Networks (TOSN)     Hybrid Journal   (Followers: 8)
ACM Transactions on Speech and Language Processing (TSLP)     Hybrid Journal   (Followers: 11)
ACM Transactions on Storage     Hybrid Journal  
ACS Applied Materials & Interfaces     Full-text available via subscription   (Followers: 21)
Acta Automatica Sinica     Full-text available via subscription   (Followers: 3)
Acta Universitatis Cibiniensis. Technical Series     Open Access  
Ad Hoc Networks     Hybrid Journal   (Followers: 11)
Adaptive Behavior     Hybrid Journal   (Followers: 11)
Advanced Engineering Materials     Hybrid Journal   (Followers: 25)
Advanced Science Letters     Full-text available via subscription   (Followers: 5)
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Advances in Artificial Intelligence     Open Access   (Followers: 15)
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Advances in Calculus of Variations     Hybrid Journal   (Followers: 2)
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Advances in Computer Science : an International Journal     Open Access   (Followers: 13)
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Advances in Data Analysis and Classification     Hybrid Journal   (Followers: 53)
Advances in Engineering Software     Hybrid Journal   (Followers: 25)
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Advances in Remote Sensing     Open Access   (Followers: 37)
Advances in Science and Research (ASR)     Open Access   (Followers: 6)
Advances in Technology Innovation     Open Access  
AEU - International Journal of Electronics and Communications     Hybrid Journal   (Followers: 8)
African Journal of Information and Communication     Open Access   (Followers: 6)
African Journal of Mathematics and Computer Science Research     Open Access   (Followers: 4)
Air, Soil & Water Research     Open Access   (Followers: 7)
AIS Transactions on Human-Computer Interaction     Open Access   (Followers: 6)
Algebras and Representation Theory     Hybrid Journal   (Followers: 1)
Algorithms     Open Access   (Followers: 9)
American Journal of Computational and Applied Mathematics     Open Access   (Followers: 3)
American Journal of Computational Mathematics     Open Access   (Followers: 4)
American Journal of Information Systems     Open Access   (Followers: 6)
American Journal of Sensor Technology     Open Access   (Followers: 2)
Anais da Academia Brasileira de Ciências     Open Access   (Followers: 2)
Analog Integrated Circuits and Signal Processing     Hybrid Journal   (Followers: 5)
Analysis in Theory and Applications     Hybrid Journal  
Animation Practice, Process & Production     Hybrid Journal   (Followers: 5)
Annals of Combinatorics     Hybrid Journal   (Followers: 3)
Annals of Data Science     Hybrid Journal   (Followers: 8)
Annals of Mathematics and Artificial Intelligence     Hybrid Journal   (Followers: 6)
Annals of Pure and Applied Logic     Open Access   (Followers: 2)
Annals of Software Engineering     Hybrid Journal   (Followers: 12)
Annual Reviews in Control     Hybrid Journal   (Followers: 6)
Anuario Americanista Europeo     Open Access  
Applicable Algebra in Engineering, Communication and Computing     Hybrid Journal   (Followers: 2)
Applied and Computational Harmonic Analysis     Full-text available via subscription   (Followers: 2)
Applied Artificial Intelligence: An International Journal     Hybrid Journal   (Followers: 14)
Applied Categorical Structures     Hybrid Journal   (Followers: 2)
Applied Clinical Informatics     Hybrid Journal   (Followers: 1)
Applied Computational Intelligence and Soft Computing     Open Access   (Followers: 12)
Applied Computer Systems     Open Access   (Followers: 1)
Applied Informatics     Open Access  
Applied Mathematics and Computation     Hybrid Journal   (Followers: 31)
Applied Medical Informatics     Open Access   (Followers: 9)
Applied Numerical Mathematics     Hybrid Journal   (Followers: 5)
Applied Soft Computing     Hybrid Journal   (Followers: 16)
Applied Spatial Analysis and Policy     Hybrid Journal   (Followers: 4)
Architectural Theory Review     Hybrid Journal   (Followers: 3)
Archive of Applied Mechanics     Hybrid Journal   (Followers: 4)
Archive of Numerical Software     Open Access  
Archives and Museum Informatics     Hybrid Journal   (Followers: 124)
Archives of Computational Methods in Engineering     Hybrid Journal   (Followers: 4)
Artifact     Hybrid Journal   (Followers: 2)
Artificial Life     Hybrid Journal   (Followers: 5)
Asia Pacific Journal on Computational Engineering     Open Access  
Asia-Pacific Journal of Information Technology and Multimedia     Open Access   (Followers: 1)
Asian Journal of Computer Science and Information Technology     Open Access  
Asian Journal of Control     Hybrid Journal  
Assembly Automation     Hybrid Journal   (Followers: 2)
at - Automatisierungstechnik     Hybrid Journal   (Followers: 1)
Australian Educational Computing     Open Access  
Automatic Control and Computer Sciences     Hybrid Journal   (Followers: 3)
Automatic Documentation and Mathematical Linguistics     Hybrid Journal   (Followers: 5)
Automatica     Hybrid Journal   (Followers: 8)
Automation in Construction     Hybrid Journal   (Followers: 6)
Autonomous Mental Development, IEEE Transactions on     Hybrid Journal   (Followers: 8)
Basin Research     Hybrid Journal   (Followers: 3)
Behaviour & Information Technology     Hybrid Journal   (Followers: 52)
Bioinformatics     Hybrid Journal   (Followers: 236)
Biomedical Engineering     Hybrid Journal   (Followers: 16)
Biomedical Engineering and Computational Biology     Open Access   (Followers: 13)
Biomedical Engineering, IEEE Reviews in     Full-text available via subscription   (Followers: 17)
Biomedical Engineering, IEEE Transactions on     Hybrid Journal   (Followers: 32)
Briefings in Bioinformatics     Hybrid Journal   (Followers: 45)
British Journal of Educational Technology     Hybrid Journal   (Followers: 122)
Broadcasting, IEEE Transactions on     Hybrid Journal   (Followers: 10)
c't Magazin fuer Computertechnik     Full-text available via subscription   (Followers: 1)
CALCOLO     Hybrid Journal  
Calphad     Hybrid Journal  
Canadian Journal of Electrical and Computer Engineering     Full-text available via subscription   (Followers: 13)
Catalysis in Industry     Hybrid Journal   (Followers: 1)
CEAS Space Journal     Hybrid Journal  
Cell Communication and Signaling     Open Access   (Followers: 1)
Central European Journal of Computer Science     Hybrid Journal   (Followers: 5)
Chaos, Solitons & Fractals     Hybrid Journal   (Followers: 3)
Chemometrics and Intelligent Laboratory Systems     Hybrid Journal   (Followers: 15)
ChemSusChem     Hybrid Journal   (Followers: 7)
China Communications     Full-text available via subscription   (Followers: 7)
Chinese Journal of Catalysis     Full-text available via subscription   (Followers: 2)
CIN Computers Informatics Nursing     Full-text available via subscription   (Followers: 12)
Circuits and Systems     Open Access   (Followers: 14)
Clean Air Journal     Full-text available via subscription   (Followers: 2)
CLEI Electronic Journal     Open Access  
Clin-Alert     Hybrid Journal   (Followers: 1)
Cluster Computing     Hybrid Journal   (Followers: 1)
Cognitive Computation     Hybrid Journal   (Followers: 4)
COMBINATORICA     Hybrid Journal  
Combustion Theory and Modelling     Hybrid Journal   (Followers: 13)
Communication Methods and Measures     Hybrid Journal   (Followers: 11)
Communication Theory     Hybrid Journal   (Followers: 19)
Communications Engineer     Hybrid Journal   (Followers: 1)
Communications in Algebra     Hybrid Journal   (Followers: 3)
Communications in Partial Differential Equations     Hybrid Journal   (Followers: 3)
Communications of the ACM     Full-text available via subscription   (Followers: 51)
Communications of the Association for Information Systems     Open Access   (Followers: 18)
COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering     Hybrid Journal   (Followers: 3)
Complex & Intelligent Systems     Open Access  
Complex Adaptive Systems Modeling     Open Access  
Complex Analysis and Operator Theory     Hybrid Journal   (Followers: 2)
Complexity     Hybrid Journal   (Followers: 6)
Complexus     Full-text available via subscription  
Composite Materials Series     Full-text available via subscription   (Followers: 9)
Computación y Sistemas     Open Access  
Computation     Open Access  
Computational and Applied Mathematics     Hybrid Journal   (Followers: 2)
Computational and Mathematical Methods in Medicine     Open Access   (Followers: 2)
Computational and Mathematical Organization Theory     Hybrid Journal   (Followers: 2)
Computational and Structural Biotechnology Journal     Open Access   (Followers: 2)
Computational and Theoretical Chemistry     Hybrid Journal   (Followers: 9)
Computational Astrophysics and Cosmology     Open Access   (Followers: 1)
Computational Biology and Chemistry     Hybrid Journal   (Followers: 12)
Computational Chemistry     Open Access   (Followers: 2)
Computational Cognitive Science     Open Access   (Followers: 1)
Computational Complexity     Hybrid Journal   (Followers: 4)
Computational Condensed Matter     Open Access  
Computational Ecology and Software     Open Access   (Followers: 8)
Computational Economics     Hybrid Journal   (Followers: 9)
Computational Geosciences     Hybrid Journal   (Followers: 13)
Computational Linguistics     Open Access   (Followers: 23)
Computational Management Science     Hybrid Journal  
Computational Mathematics and Modeling     Hybrid Journal   (Followers: 8)
Computational Mechanics     Hybrid Journal   (Followers: 4)
Computational Methods and Function Theory     Hybrid Journal  
Computational Molecular Bioscience     Open Access   (Followers: 2)
Computational Optimization and Applications     Hybrid Journal   (Followers: 7)
Computational Particle Mechanics     Hybrid Journal   (Followers: 1)
Computational Research     Open Access   (Followers: 1)
Computational Science and Discovery     Full-text available via subscription   (Followers: 2)
Computational Science and Techniques     Open Access  
Computational Statistics     Hybrid Journal   (Followers: 13)
Computational Statistics & Data Analysis     Hybrid Journal   (Followers: 28)
Computer     Full-text available via subscription   (Followers: 81)
Computer Aided Surgery     Hybrid Journal   (Followers: 3)
Computer Applications in Engineering Education     Hybrid Journal   (Followers: 6)
Computer Communications     Hybrid Journal   (Followers: 10)
Computer Engineering and Applications Journal     Open Access   (Followers: 5)
Computer Journal     Hybrid Journal   (Followers: 7)
Computer Methods in Applied Mechanics and Engineering     Hybrid Journal   (Followers: 22)
Computer Methods in Biomechanics and Biomedical Engineering     Hybrid Journal   (Followers: 10)
Computer Methods in the Geosciences     Full-text available via subscription   (Followers: 1)
Computer Music Journal     Hybrid Journal   (Followers: 13)
Computer Physics Communications     Hybrid Journal   (Followers: 6)
Computer Science - Research and Development     Hybrid Journal   (Followers: 7)
Computer Science and Engineering     Open Access   (Followers: 17)
Computer Science and Information Technology     Open Access   (Followers: 11)
Computer Science Education     Hybrid Journal   (Followers: 12)
Computer Science Journal     Open Access   (Followers: 20)
Computer Science Master Research     Open Access   (Followers: 10)

        1 2 3 4 5 6 | Last

Journal Cover Annals of Pure and Applied Logic
  [SJR: 1.19]   [H-I: 33]   [2 followers]  Follow
  This is an Open Access Journal Open Access journal
   ISSN (Print) 0168-0072
   Published by Elsevier Homepage  [3042 journals]
  • Full-splitting Miller trees and infinitely often equal reals

    • Authors: Yurii Khomskii; Giorgio Laguzzi
      Pages: 1491 - 1506
      Abstract: Publication date: August 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 8
      Author(s): Yurii Khomskii, Giorgio Laguzzi
      We investigate two closely related partial orders of trees on ω ω : the full-splitting Miller trees and the infinitely often equal trees, as well as their corresponding σ-ideals. The former notion was considered by Newelski and Rosłanowski while the latter involves a correction of a result of Spinas. We consider some Marczewski-style regularity properties based on these trees, which turn out to be closely related to the property of Baire, and look at the dichotomies of Newelski–Rosłanowski and Spinas for higher projective pointclasses. We also provide some insight concerning a question of Fremlin whether one can add an infinitely often equal real without adding a Cohen real, which was recently solved by Zapletal.

      PubDate: 2017-05-21T15:55:03Z
      DOI: 10.1016/j.apal.2017.02.001
  • On the decidability of the theory of modules over the ring of algebraic

    • Authors: Sonia L'Innocente; Carlo Toffalori; Gena Puninski
      Pages: 1507 - 1516
      Abstract: Publication date: August 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 8
      Author(s): Sonia L'Innocente, Carlo Toffalori, Gena Puninski
      We will prove that the theory of all modules over the ring of algebraic integers is decidable.

      PubDate: 2017-05-21T15:55:03Z
      DOI: 10.1016/j.apal.2017.02.003
  • Proof lengths for instances of the Paris–Harrington principle

    • Authors: Anton Freund
      Pages: 1361 - 1382
      Abstract: Publication date: July 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 7
      Author(s): Anton Freund
      As Paris and Harrington have famously shown, Peano Arithmetic does not prove that for all numbers k , m , n there is an N which satisfies the statement PH ( k , m , n , N ) : For any k-coloring of its n-element subsets the set { 0 , … , N − 1 } has a large homogeneous subset of size ≥m. At the same time very weak theories can establish the Σ 1 -statement ∃ N PH ( k ‾ , m ‾ , n ‾ , N ) for any fixed parameters k , m , n . Which theory, then, does it take to formalize natural proofs of these instances? It is known that ∀ m ∃ N PH ( k ‾ , m , n ‾ , N ) has a natural and short proof (relative to n and k) by Σ n − 1 -induction. In contrast, we show that there is an elementary function e such that any proof of ∃ N PH ( e ( n ) ‾ , n + 1 ‾ , n ‾ , N ) by Σ n − 2 -induction is ridiculously long. In order to establish this result on proof lengths we give a computational analysis of slow provability, a notion introduced by Sy-David Friedman, Rathjen and Weiermann. We will see that slow uniform Σ 1 -reflection is related to a function that has a considerably lower growth rate than F ε 0 but dominates all functions F α with α < ε 0 in the fast-growing hierarchy.

      PubDate: 2017-05-01T14:19:49Z
      DOI: 10.1016/j.apal.2017.01.004
  • The Gamma question for many-one degrees

    • Authors: Matthew Harrison-Trainor
      Pages: 1396 - 1405
      Abstract: Publication date: July 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 7
      Author(s): Matthew Harrison-Trainor
      A set A is coarsely computable with density r ∈ [ 0 , 1 ] if there is an algorithm for deciding membership in A which always gives a (possibly incorrect) answer, and which gives a correct answer with density at least r. To any Turing degree a we can assign a value Γ T ( a ) : the minimum, over all sets A in a, of the highest density at which A is coarsely computable. The closer Γ T ( a ) is to 1, the closer a is to being computable. Andrews, Cai, Diamondstone, Jockusch, and Lempp noted that Γ T can take on the values 0, 1/2, and 1, but not any values in strictly between 1/2 and 1. They asked whether the value of Γ T can be strictly between 0 and 1/2. This is the Gamma question. Replacing Turing degrees by many-one degrees, we get an analogous question, and the same arguments show that Γ m can take on the values 0, 1/2, and 1, but not any values strictly between 1/2 and 1. We will show that for any r ∈ [ 0 , 1 / 2 ] , there is an m-degree a with Γ m ( a ) = r . Thus the range of Γ m is [ 0 , 1 / 2 ] ∪ { 1 } . Benoit Monin has recently announced a solution to the Gamma question for Turing degrees. Interestingly, his solution gives the opposite answer: the only possible values of Γ T are 0, 1/2, and 1.

      PubDate: 2017-05-01T14:19:49Z
      DOI: 10.1016/j.apal.2017.01.006
  • Propositional team logics

    • Authors: Fan Yang; Jouko Väänänen
      Pages: 1406 - 1441
      Abstract: Publication date: July 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 7
      Author(s): Fan Yang, Jouko Väänänen
      We consider team semantics for propositional logic, continuing [34]. In team semantics the truth of a propositional formula is considered in a set of valuations, called a team, rather than in an individual valuation. This offers the possibility to give meaning to concepts such as dependence, independence and inclusion. We associate with every formula ϕ based on finitely many propositional variables the set 〚 ϕ 〛 of teams that satisfy ϕ. We define a maximal propositional team logic in which every set of teams is definable as 〚 ϕ 〛 for suitable ϕ. This requires going beyond the logical operations of classical propositional logic. We exhibit a hierarchy of logics between the smallest, viz. classical propositional logic, and the maximal propositional team logic. We characterize these different logics in several ways: first syntactically by their logical operations, and then semantically by the kind of sets of teams they are capable of defining. In several important cases we are able to find complete axiomatizations for these logics.

      PubDate: 2017-05-01T14:19:49Z
      DOI: 10.1016/j.apal.2017.01.007
  • Neostability in countable homogeneous metric spaces

    • Authors: Gabriel Conant
      Pages: 1442 - 1471
      Abstract: Publication date: July 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 7
      Author(s): Gabriel Conant
      Given a countable, totally ordered commutative monoid R = ( R , ⊕ , ≤ , 0 ) , with least element 0, there is a countable, universal and ultrahomogeneous metric space U R with distances in R . We refer to this space as the R -Urysohn space, and consider the theory of U R in a binary relational language of distance inequalities. This setting encompasses many classical structures of varying model theoretic complexity, including the rational Urysohn space, the free nth roots of the complete graph (e.g. the random graph when n = 2 ), and theories of refining equivalence relations (viewed as ultrametric spaces). We characterize model theoretic properties of Th ( U R ) by algebraic properties of R , many of which are first-order in the language of ordered monoids. This includes stability, simplicity, and Shelah's SOP n -hierarchy. Using the submonoid of idempotents in R , we also characterize superstability, supersimplicity, and weak elimination of imaginaries. Finally, we give necessary conditions for elimination of hyperimaginaries, which further develops previous work of Casanovas and Wagner.

      PubDate: 2017-05-01T14:19:49Z
      DOI: 10.1016/j.apal.2017.01.008
  • The uniform content of partial and linear orders

    • Authors: Eric P. Astor; Damir D. Dzhafarov; Reed Solomon; Jacob Suggs
      Pages: 1153 - 1171
      Abstract: Publication date: June 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 6
      Author(s): Eric P. Astor, Damir D. Dzhafarov, Reed Solomon, Jacob Suggs
      The principle ADS asserts that every linear order on ω has an infinite ascending or descending sequence. This has been studied extensively in the reverse mathematics literature, beginning with the work of Hirschfeldt and Shore [16]. We introduce the principle ADC , which asserts that every such linear order has an infinite ascending or descending chain. The two are easily seen to be equivalent over the base system RCA 0 of second order arithmetic; they are even computably equivalent. However, we prove that ADC is strictly weaker than ADS under Weihrauch (uniform) reducibility. In fact, we show that even the principle SADS , which is the restriction of ADS to linear orders of type ω + ω ⁎ , is not Weihrauch reducible to ADC . In this connection, we define a more natural stable form of ADS that we call General - SADS , which is the restriction of ADS to linear orders of type k + ω , ω + ω ⁎ , or ω + k , where k is a finite number. We define General - SADC analogously. We prove that General - SADC is not Weihrauch reducible to SADS , and so in particular, each of SADS and SADC is strictly weaker under Weihrauch reducibility than its general version. Finally, we turn to the principle CAC , which asserts that every partial order on ω has an infinite chain or antichain. This has two previously studied stable variants, SCAC and WSCAC , which were introduced by Hirschfeldt and Jockusch [16], and by Jockusch, Kastermans, Lempp, Lerman, and Solomon [19], respectively, and which are known to be equivalent over RCA 0 . Here, we show that SCAC is strictly weaker than WSCAC under even computable reducibility.

      PubDate: 2017-04-02T17:28:22Z
      DOI: 10.1016/j.apal.2016.11.010
  • Dominating the Erdős–Moser theorem in reverse mathematics

    • Authors: Ludovic Patey
      Pages: 1172 - 1209
      Abstract: Publication date: June 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 6
      Author(s): Ludovic Patey
      The Erdős–Moser theorem ( EM ) states that every infinite tournament has an infinite transitive subtournament. This principle plays an important role in the understanding of the computational strength of Ramsey's theorem for pairs ( RT 2 2 ) by providing an alternate proof of RT 2 2 in terms of EM and the ascending descending sequence principle ( ADS ). In this paper, we study the computational weakness of EM and construct a standard model (ω-model) of simultaneously EM , weak König's lemma and the cohesiveness principle, which is not a model of the atomic model theorem. This separation answers a question of Hirschfeldt, Shore and Slaman, and shows that the weakness of the Erdős–Moser theorem goes beyond the separation of EM from ADS proven by Lerman, Solomon and Towsner.

      PubDate: 2017-04-02T17:28:22Z
      DOI: 10.1016/j.apal.2016.11.011
  • The countable admissible ordinal equivalence relation

    • Authors: William Chan
      Pages: 1224 - 1246
      Abstract: Publication date: June 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 6
      Author(s): William Chan
      Let F ω 1 be the countable admissible ordinal equivalence relation defined on 2 ω by x F ω 1 y if and only if ω 1 x = ω 1 y . Some invariant descriptive set theoretic properties of F ω 1 will be explored using infinitary logic in countable admissible fragments as the main tool. Marker showed F ω 1 is not the orbit equivalence relation of a continuous action of a Polish group on 2 ω . Becker stengthened this to show F ω 1 is not even the orbit equivalence relation of a Δ 1 1 action of a Polish group. However, Montalbán has shown that F ω 1 is Δ 1 1 reducible to an orbit equivalence relation of a Polish group action, in fact, F ω 1 is classifiable by countable structures. It will be shown here that F ω 1 must be classified by structures of high Scott rank. Let E ω 1 denote the equivalence of order types of reals coding well-orderings. If E and F are two equivalence relations on Polish spaces X and Y, respectively, E ≤ a Δ 1 1 F denotes the existence of a Δ 1 1 function f : X → Y which is a reduction of E to F, except possibly on countably many classes of E. Using a result of Zapletal, the existence of a measurable cardinal implies E ω 1 ≤ a Δ 1 1 F ω 1 . However, it will be shown that in Gödel's constructible universe L (and set generic extensions of L), E ω 1 ≤ a Δ 1 1 F ω 1 is false. Lastly, the techniques of the previous result will be used to show that in L (and set gener...
      PubDate: 2017-04-02T17:28:22Z
      DOI: 10.1016/j.apal.2016.12.002
  • Bar recursion over finite partial functions

    • Authors: Paulo Oliva; Thomas Powell
      Pages: 887 - 921
      Abstract: Publication date: May 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 5
      Author(s): Paulo Oliva, Thomas Powell
      We introduce a new, demand-driven variant of Spector's bar recursion in the spirit of the Berardi–Bezem–Coquand functional of [4]. The recursion takes place over finite partial functions u, where the control parameter ω, used in Spector's bar recursion to terminate the computation at sequences s satisfying ω ( s ˆ ) < s , now acts as a guide for deciding exactly where to make bar recursive updates, terminating the computation whenever ω ( u ˆ ) ∈ dom ( u ) . We begin by exploring theoretical aspects of this new form of recursion, then in the main part of the paper we show that demand-driven bar recursion can be directly used to give an alternative functional interpretation of classical countable choice. We provide a short case study as an illustration, in which we extract a new bar recursive program from the proof that there is no injection from N → N to N , and compare this with the program that would be obtained using Spector's original variant. We conclude by formally establishing that our new bar recursor is primitive recursively equivalent to the original Spector bar recursion, and thus defines the same class of functionals when added to Gödel's system T .

      PubDate: 2017-03-08T09:28:37Z
      DOI: 10.1016/j.apal.2016.11.003
  • Mitchell's theorem revisited

    • Authors: Thomas Gilton; John Krueger
      Pages: 922 - 1016
      Abstract: Publication date: May 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 5
      Author(s): Thomas Gilton, John Krueger
      Mitchell's theorem on the approachability ideal states that it is consistent relative to a greatly Mahlo cardinal that there is no stationary subset of ω 2 ∩ cof ( ω 1 ) in the approachability ideal I [ ω 2 ] . In this paper we give a new proof of Mitchell's theorem, deriving it from an abstract framework of side condition methods.

      PubDate: 2017-03-08T09:28:37Z
      DOI: 10.1016/j.apal.2016.11.004
  • Honest elementary degrees and degrees of relative provability without the
           cupping property

    • Authors: Paul Shafer
      Pages: 1017 - 1031
      Abstract: Publication date: May 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 5
      Author(s): Paul Shafer
      An element a of a lattice cups to an element b > a if there is a c < b such that a ∪ c = b . An element of a lattice has the cupping property if it cups to every element above it. We prove that there are non-zero honest elementary degrees that do not have the cupping property, which answers a question of Kristiansen, Schlage-Puchta, and Weiermann. In fact, we show that if b is a sufficiently large honest elementary degree, then b has the anti-cupping property, which means that there is an a with 0 < E a < E b that does not cup to b. For comparison, we also modify a result of Cai to show, in several versions of the degrees of relative provability that are closely related to the honest elementary degrees, that in fact all non-zero degrees have the anti-cupping property, not just sufficiently large degrees.

      PubDate: 2017-03-08T09:28:37Z
      DOI: 10.1016/j.apal.2016.11.005
  • Spatial logic of tangled closure operators and modal mu-calculus

    • Authors: Robert Goldblatt; Ian Hodkinson
      Pages: 1032 - 1090
      Abstract: Publication date: May 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 5
      Author(s): Robert Goldblatt, Ian Hodkinson
      There has been renewed interest in recent years in McKinsey and Tarski's interpretation of modal logic in topological spaces and their proof that S4 is the logic of any separable dense-in-itself metric space. Here we extend this work to the modal mu-calculus and to a logic of tangled closure operators that was developed by Fernández-Duque after these two languages had been shown by Dawar and Otto to have the same expressive power over finite transitive Kripke models. We prove that this equivalence remains true over topological spaces. We extend the McKinsey–Tarski topological ‘dissection lemma’. We also take advantage of the fact (proved by us elsewhere) that various tangled closure logics with and without the universal modality ∀ have the finite model property in Kripke semantics. These results are used to construct a representation map (also called a d-p-morphism) from any dense-in-itself metric space X onto any finite connected locally connected serial transitive Kripke frame. This yields completeness theorems over X for a number of languages: (i) the modal mu-calculus with the closure operator ◇; (ii) ◇ and the tangled closure operators 〈 t 〉 (in fact 〈 t 〉 can express ◇); (iii) ◇ , ∀ ; (iv) ◇ , ∀ , 〈 t 〉 ; (v) the derivative operator 〈 d 〉 ; (vi) 〈 d 〉 and the associated tangled closure operators 〈 d t 〉 ; (vii) 〈 d 〉 , ∀ ; (viii) 〈 d 〉 , ∀ , 〈 d t 〉 . Soundness also holds, if: (a) for languages with ∀, X is connected; (b) for languages with 〈 d 〉 , X validates the well-known axiom G 1 . For countable languages without ∀, we prove strong completeness. We also show that in the presence of ∀, strong completeness fails if X is compact and locally connected.

      PubDate: 2017-03-08T09:28:37Z
      DOI: 10.1016/j.apal.2016.11.006
  • Characterizing model-theoretic dividing lines via collapse of generalized

    • Authors: Vincent Guingona; Cameron Donnay Hill; Lynn Scow
      Pages: 1091 - 1111
      Abstract: Publication date: May 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 5
      Author(s): Vincent Guingona, Cameron Donnay Hill, Lynn Scow
      We use the notion of collapse of generalized indiscernible sequences to classify various model theoretic dividing lines. In particular, we use collapse of n-multi-order indiscernibles to characterize op-dimension n; collapse of function-space indiscernibles (i.e. parameterized equivalence relations) to characterize rosy theories; and finally, convex equivalence relation indiscernibles to characterize NTP2 theories.

      PubDate: 2017-03-08T09:28:37Z
      DOI: 10.1016/j.apal.2016.11.007
  • Characterizing large cardinals in terms of layered posets

    • Authors: Sean Cox; Philipp Lücke
      Pages: 1112 - 1131
      Abstract: Publication date: May 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 5
      Author(s): Sean Cox, Philipp Lücke
      Given an uncountable regular cardinal κ, a partial order is κ-stationarily layered if the collection of regular suborders of P of cardinality less than κ is stationary in P κ ( P ) . We show that weak compactness can be characterized by this property of partial orders by proving that an uncountable regular cardinal κ is weakly compact if and only if every partial order satisfying the κ-chain condition is κ-stationarily layered. We prove a similar result for strongly inaccessible cardinals. Moreover, we show that the statement that all κ-Knaster partial orders are κ-stationarily layered implies that κ is a Mahlo cardinal and every stationary subset of κ reflects. This shows that this statement characterizes weak compactness in canonical inner models. In contrast, we show that it is also consistent that this statement holds at a non-weakly compact cardinal.

      PubDate: 2017-03-08T09:28:37Z
      DOI: 10.1016/j.apal.2016.11.008
  • Germinal theories in Łukasiewicz logic

    • Authors: Leonardo Manuel Cabrer; Daniele Mundici
      Pages: 1132 - 1151
      Abstract: Publication date: May 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 5
      Author(s): Leonardo Manuel Cabrer, Daniele Mundici
      Differently from boolean logic, in Łukasiewicz infinite-valued propositional logic Ł∞ the theory Θ max ⁡ , v consisting of all formulas satisfied by a model v ∈ [ 0 , 1 ] n is not the only one having v as its unique model: indeed, there is a smallest such theory Θ min ⁡ , v , the germinal theory at v, which in general is strictly contained in Θ max ⁡ , v . The Lindenbaum algebra of Θ max ⁡ , v is promptly seen to coincide with the subalgebra of the standard MV-algebra [ 0 , 1 ] generated by the coordinates of v. The description of the Lindenbaum algebras of germinal theories in two variables is our main aim in this paper. As a basic prerequisite of independent interest, we prove that for any models v and w the germinal theories Θ min ⁡ , v and Θ min ⁡ , w have isomorphic Lindenbaum algebras iff v and w have the same orbit under the action of the affine group over the integers.

      PubDate: 2017-03-08T09:28:37Z
      DOI: 10.1016/j.apal.2016.11.009
  • Polish G-spaces and continuous logic

    • Authors: A. Ivanov; B. Majcher-Iwanow
      Pages: 749 - 775
      Abstract: Publication date: April 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 4
      Author(s): A. Ivanov, B. Majcher-Iwanow
      We extend the generalised model theory of H. Becker from [2] to the case of Polish G-spaces when G is an arbitrary Polish group. Our approach is inspired by logic actions of Polish groups which arise in continuous logic.

      PubDate: 2017-02-04T06:18:23Z
      DOI: 10.1016/j.apal.2016.11.002
  • Covering the recursive sets

    • Authors: Bjørn Kjos-Hanssen; Frank Stephan; Sebastiaan A. Terwijn
      Pages: 804 - 823
      Abstract: Publication date: April 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 4
      Author(s): Bjørn Kjos-Hanssen, Frank Stephan, Sebastiaan A. Terwijn
      We give solutions to two of the questions in a paper by Brendle, Brooke-Taylor, Ng and Nies. Our examples derive from a 2014 construction by Khan and Miller as well as new direct constructions using martingales. At the same time, we introduce the concept of i.o. subuniformity and relate this concept to recursive measure theory. We prove that there are classes closed downwards under Turing reducibility that have recursive measure zero and that are not i.o. subuniform. This shows that there are examples of classes that cannot be covered with methods other than probabilistic ones. It is easily seen that every set of hyperimmune degree can cover the recursive sets. We prove that there are both examples of hyperimmune-free degree that can and that cannot compute such a cover.

      PubDate: 2017-02-04T06:18:23Z
      DOI: 10.1016/j.apal.2016.10.017
  • Ordinals and graph decompositions

    • Authors: Stephen Flood
      Pages: 824 - 839
      Abstract: Publication date: April 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 4
      Author(s): Stephen Flood
      The theory of simplicial graph decompositions studies the infinite graphs that are built from a sequence of irreducible graphs which are attached together at complete subgraphs. In this paper, we study the logical complexity of deciding if a graph is prime decomposable. A large part of this analysis involves determining which ordinals must appear in these types of decompositions. A result of Diestel says that every countable simplicial tree decomposition can be rearranged to have length at most ω. We show that no such ordinal bound can be found for the lengths of non-tree decompositions. More generally, we show that for each ordinal σ, there is a decomposable graph whose shortest simplicial decomposition has length exactly σ. Adapting this argument, we show that the index set of decomposable computable graphs DECOMP is Π 1 1 hard by showing that WO is 1-reducible to DECOMP .

      PubDate: 2017-02-04T06:18:23Z
      DOI: 10.1016/j.apal.2016.10.016
  • Clustered cell decomposition in P-minimal structures

    • Authors: Saskia Chambille; Pablo Cubides Kovacsics; Eva Leenknegt
      Abstract: Publication date: Available online 9 June 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Saskia Chambille, Pablo Cubides Kovacsics, Eva Leenknegt
      We prove that in a P-minimal structure, every definable set can be partitioned as a finite union of classical cells and regular clustered cells. This is a generalization of previously known cell decomposition results by Denef and Mourgues, which were dependent on the existence of definable Skolem functions. Clustered cells have the same geometric structure as classical, Denef-type cells, but do not have a definable function as center. Instead, the center is given by a definable set whose fibers are finite unions of balls.

      PubDate: 2017-06-10T17:06:33Z
      DOI: 10.1016/j.apal.2017.06.002
  • A microscopic approach to Souslin-tree constructions. Part I

    • Authors: Ari Meir Brodsky; Assaf Rinot
      Abstract: Publication date: Available online 8 June 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Ari Meir Brodsky, Assaf Rinot
      We propose a parameterized proxy principle from which κ-Souslin trees with various additional features can be constructed, regardless of the identity of κ. We then introduce the microscopic approach, which is a simple method for deriving trees from instances of the proxy principle. As a demonstration, we give a construction of a coherent κ-Souslin tree that applies also for κ inaccessible. We then carry out a systematic study of the consistency of instances of the proxy principle, distinguished by the vector of parameters serving as its input. Among other things, it will be shown that all known ⋄-based constructions of κ-Souslin trees may be redirected through this new proxy principle.

      PubDate: 2017-06-10T17:06:33Z
      DOI: 10.1016/j.apal.2017.05.003
  • Ramsey type properties of ideals

    • Abstract: Publication date: Available online 7 June 2017
      Source:Annals of Pure and Applied Logic
      Author(s): M. Hrušák, D. Meza-Alcántara, E. Thümmel, C. Uzcátegui
      We study several combinatorial properties of (mostly definable) ideals on countable sets. In several cases, we identify critical ideals for such properties in the Katětov order. In particular, the ideal R generated by the homogeneous subsets of the random graph is critical for the Ramsey property. The question as to whether there is a tall definable Ramsey ideal is raised and studied. It is shown that no tall F σ ideal is Ramsey, while there is a tall co-analytic Ramsey ideal.

      PubDate: 2017-06-10T17:06:33Z
  • Determinacy in Third Order Arithmetic

    • Authors: Sherwood Hachtman
      Abstract: Publication date: Available online 1 June 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Sherwood Hachtman
      We investigate the strength of open and clopen determinacy of perfect information games with real number moves in the context of third order arithmetic. This work is conducted in a framework developed in 2015 by Schweber [12], who showed that in this setting, open determinacy ( Σ 1 R - DET ) is not implied by clopen determinacy ( Δ 1 R - DET ). We give a new forcing-free proof of this result by isolating a level of L witnessing this separation. We give a notion of β-absoluteness in the context of third-order arithmetic, and show that this level of L is a β-model; combining this with our previous results on the strength of Borel determinacy, we show that Σ 4 0 -DET , determinacy for games on ω with Σ 4 0 payoff, is sandwiched between Σ 1 R - DET and Δ 1 R - DET in terms of β-consistency strength.

      PubDate: 2017-06-06T16:45:59Z
      DOI: 10.1016/j.apal.2017.05.004
  • Increasing sentences in Simple Type Theory

    • Authors: Panagiotis Rouvelas
      Abstract: Publication date: Available online 26 May 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Panagiotis Rouvelas
      We introduce the notion of pseudo-increasing sentence, and prove that all such sentences are decidable by a weak subtheory of Simple Type Theory with infinitely many zero-type elements. We then present the consequences of this result to Quine's theory of “New Foundations” (NF). In particular, we prove the decidability of certain universal-existential sentences, and establish the consistency of a subtheory of NF.

      PubDate: 2017-06-01T16:29:34Z
      DOI: 10.1016/j.apal.2017.05.002
  • Uniform interpolation and compact congruences

    • Authors: Samuel van; Gool George Metcalfe Constantine Tsinakis
      Abstract: Publication date: Available online 26 May 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Samuel J. van Gool, George Metcalfe, Constantine Tsinakis
      Uniform interpolation properties are defined for equational consequence in a variety of algebras and related to properties of compact congruences on first the free and then the finitely presented algebras of the variety. It is also shown, following related results of Ghilardi and Zawadowski, that a combination of these properties provides a sufficient condition for the first-order theory of the variety to admit a model completion.

      PubDate: 2017-05-26T16:09:09Z
  • Universal graphs at ℵω1+1

    • Authors: Jacob Davis
      Abstract: Publication date: Available online 3 May 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Jacob Davis
      Starting from a supercompact cardinal we build a model in which 2 ℵ ω 1 = 2 ℵ ω 1 + 1 = ℵ ω 1 + 3 but there is a jointly universal family of size ℵ ω 1 + 2 of graphs on ℵ ω 1 + 1 . The same technique will work for any uncountable cardinal in place of ω 1 .

      PubDate: 2017-05-07T14:48:17Z
      DOI: 10.1016/j.apal.2017.04.005
  • Reducts of the Henson graphs with a constant

    • Abstract: Publication date: July 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 7
      Author(s): András Pongrácz
      Let ( H n , E ) denote the Henson graph, the unique countable homogeneous graph whose age consists of all finite K n -free graphs. In this note the reducts of the Henson graphs with a constant are determined up to first-order interdefinability. It is shown that up to first-order interdefinability ( H 3 , E , 0 ) has 13 reducts and ( H n , E , 0 ) has 16 reducts for n ≥ 4 .

      PubDate: 2017-05-01T14:19:49Z
  • Addendum to: “The Bolzano–Weierstrass theorem is the jump of weak
           Kőnig's lemma” [Ann. Pure Appl. Logic 163 (6) (2012) 623–655]

    • Authors: Vasco Brattka; Andrea Cettolo; Guido Gherardi; Alberto Marcone; Matthias Schröder
      Abstract: Publication date: Available online 29 April 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Vasco Brattka, Andrea Cettolo, Guido Gherardi, Alberto Marcone, Matthias Schröder
      The purpose of this addendum is to close a gap in the proof of [1, Theorem 11.2], which characterizes the computational content of the Bolzano–Weierstraß Theorem for arbitrary computable metric spaces.

      PubDate: 2017-05-01T14:19:49Z
      DOI: 10.1016/j.apal.2017.04.004
  • Imaginaries in bounded pseudo real closed fields

    • Authors: Samaria Montenegro
      Abstract: Publication date: Available online 21 April 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Samaria Montenegro
      The main result of this paper is that if M is a bounded PRC field, then T h ( M ) eliminates imaginaries in the language of rings expanded by constant symbols. As corollary of the elimination of imaginaries and the fact that the algebraic closure (in the sense of model theory) defines a pregeometry we obtain that the complete theory of a bounded PRC field is superrosy of U th -rank 1.

      PubDate: 2017-04-23T21:52:32Z
      DOI: 10.1016/j.apal.2017.04.003
  • Finding a field in a Zariski-like structure

    • Authors: Kaisa Kangas
      Abstract: Publication date: Available online 6 April 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Kaisa Kangas
      We show that if M is a Zariski-like structure (see [6]) and the canonical pregeometry obtained from the bounded closure operator (bcl) is non locally modular, then M interprets either an algebraically closed field or a non-classical group.

      PubDate: 2017-04-09T20:53:23Z
      DOI: 10.1016/j.apal.2017.04.002
  • Ceres in Intuitionistic Logic

    • Authors: David Cerna; Alexander Leitsch; Giselle Reis; Simon Wolfsteiner
      Abstract: Publication date: Available online 5 April 2017
      Source:Annals of Pure and Applied Logic
      Author(s): David Cerna, Alexander Leitsch, Giselle Reis, Simon Wolfsteiner
      In this paper we present a procedure allowing the extension of a CERES-based cut-elimination method to intuitionistic logic. Previous results concerning this problem manage to capture fragments of intuitionistic logic, but in many essential cases structural constraints were violated during normal form construction resulting in a classical proof. The heart of the CERES method is the resolution calculus, which ignores the structural constraints of the well known intuitionistic sequent calculi. We propose, as a method of avoiding the structural violations, the generalization of resolution from the resolving of clauses to the resolving of cut-free proofs, in other words, what we call proof resolution. The result of proof resolution is a cut-free proof rather than a clause. Note that resolution on ground clauses is essentially atomic cut, thus using proof resolution to construct cut-free proofs one would need to join the two proofs together and remove the atoms which where resolved. To efficiently perform this joining (and guarantee that the resulting cut-free proof is intuitionistic) we develop the concept of proof subsumption (similar to clause subsumption) and indexed resolution, a refinement indexing atoms by their corresponding positions in the cut formula. Proof subsumption serves as a tool to prove the completeness of the new method CERES-i, and indexed resolution provides an efficient strategy for the joining of two proofs which is in general a nondeterministic search. Such a refinement is essential for any attempt to implement this method. Finally we compare the complexity of CERES-i with that of Gentzen-based methods.

      PubDate: 2017-04-09T20:53:23Z
      DOI: 10.1016/j.apal.2017.04.001
  • Condensational equivalence, equimorphism, elementary equivalence and
           similar similarities

    • Authors: Nenad
      Abstract: Publication date: June 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 6
      Author(s): Miloš S. Kurilić, Nenad Morača
      We investigate the interplay between several similarities of relational structures: the condensational equivalence (defined by X ∼ c Y iff there are bijective homomorphisms f : X → Y and g : Y → X ), the isomorphism, the equimorphism (bi-embedability), the elementary equivalence and the similarities of structures determined by some similarities of their self-embedding monoids. It turns out that the Hasse diagram describing the hierarchy of these equivalence relations restricted to the set Mod L ( κ ) of all L-structures of size κ collapses significantly for a finite cardinal κ or for a unary language L, while for infinite structures of non-unary languages we have a large diversity.

      PubDate: 2017-04-02T17:28:22Z
  • Abelian C-minimal valued groups

    • Authors: F. Delon; P. Simonetta
      Abstract: Publication date: Available online 29 March 2017
      Source:Annals of Pure and Applied Logic
      Author(s): F. Delon, P. Simonetta
      We classify abelian C-minimal valued groups up to pure and elementary extensions and small modifications. We define first the notion of almost regularity for abelian valued groups. Then we introduce on the chain of valuations the structure which enables us to characterize C-minimal abelian valued groups as the almost regular ones with an o-minimal chain.

      PubDate: 2017-04-02T17:28:22Z
      DOI: 10.1016/j.apal.2017.03.008
  • Superstability from categoricity in abstract elementary classes

    • Authors: Will Boney; Rami Grossberg; Monica M. VanDieren; Sebastien Vasey
      Abstract: Publication date: Available online 27 March 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Will Boney, Rami Grossberg, Monica M. VanDieren, Sebastien Vasey
      Starting from an abstract elementary class with no maximal models, Shelah and Villaveces have shown (assuming instances of diamond) that categoricity implies a superstability-like property for nonsplitting, a particular notion of independence. We generalize their result as follows: given any abstract notion of independence for Galois (orbital) types over models, we derive that the notion satisfies a superstability property provided that the class is categorical and satisfies a weakening of amalgamation. This extends the Shelah–Villaveces result (the independence notion there was splitting) as well as a result of the first and second author where the independence notion was coheir. The argument is in ZFC and fills a gap in the Shelah–Villaveces proof.

      PubDate: 2017-04-02T17:28:22Z
      DOI: 10.1016/j.apal.2017.01.005
  • Shelah's eventual categoricity conjecture in universal classes: Part I

    • Authors: Sebastien Vasey
      Abstract: Publication date: Available online 22 March 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Sebastien Vasey
      We prove: Theorem 0.1 Let K be a universal class. If K is categorical in cardinals of arbitrarily high cofinality, then K is categorical on a tail of cardinals. The proof stems from ideas of Adi Jarden and Will Boney, and also relies on a deep result of Shelah. As opposed to previous works, the argument is in ZFC and does not use the assumption of categoricity in a successor cardinal. The argument generalizes to abstract elementary classes (AECs) that satisfy a locality property and where certain prime models exist. Moreover assuming amalgamation we can give an explicit bound on the Hanf number and get rid of the cofinality restrictions: Theorem 0.2 Let K be an AEC with amalgamation. Assume that K is fully LS ( K ) -tame and short and has primes over sets of the form M ∪ { a } . Write H 2 : = ℶ ( 2 ℶ ( 2 LS ( K ) ) + ) + . If K is categorical in a λ > H 2 , then K is categorical in all λ ′ ≥ H 2 .

      PubDate: 2017-04-02T17:28:22Z
      DOI: 10.1016/j.apal.2017.03.003
  • Erratum to: “Scott rank of Polish metric spaces” [Ann. Pure Appl.
           Logic 165 (12) (2014) 1919–1929]

    • Authors: Michal Doucha
      Abstract: Publication date: Available online 21 March 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Michal Doucha

      PubDate: 2017-04-02T17:28:22Z
      DOI: 10.1016/j.apal.2017.03.006
  • Homology groups of types in stable theories and the Hurewicz

    • Authors: John Goodrick; Byunghan Kim; Alexei Kolesnikov
      Abstract: Publication date: Available online 18 March 2017
      Source:Annals of Pure and Applied Logic
      Author(s): John Goodrick, Byunghan Kim, Alexei Kolesnikov
      We give an explicit description of the homology group H n ( p ) of a strong type p in any stable theory under the assumption that for every non-forking extension q of p the groups H i ( q ) are trivial for 2 ≤ i < n . The group H n ( p ) turns out to be isomorphic to the automorphism group of a certain part of the algebraic closure of n independent realizations of p; it follows from the authors' earlier work that such a group must be abelian. We call this the “Hurewicz correspondence” by analogy with the Hurewicz Theorem in algebraic topology.

      PubDate: 2017-04-02T17:28:22Z
      DOI: 10.1016/j.apal.2017.03.007
  • The strength of infinitary Ramseyan principles can be accessed by their

    • Authors: Andrey Bovykin; Andreas Weiermann
      Abstract: Publication date: Available online 14 March 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Andrey Bovykin, Andreas Weiermann
      In this article, we conduct a model-theoretic investigation of three infinitary Ramseyan statements: the Infinite Ramsey Theorem for pairs and two colours ( RT 2 2 ), the Canonical Ramsey Theorem for pairs ( CRT 2 ) and the Regressive Ramsey Theorem for pairs ( RegRT 2 ). We approximate the logical strength of these principles by the strength of their first-order iterated versions, known as density principles. We then investigate their logical strength using strong initial segments of models of Peano Arithmetic, in the spirit of the classical article by Paris and Kirby, hereby re-proving old results model-theoretically. The article is concluded by a discussion of two further outreaches of densities. One is a further investigation of the strength of the Ramsey Theorem for pairs. The other deals with the asymptotics of the standard Ramsey function R 2 2 .

      PubDate: 2017-04-02T17:28:22Z
      DOI: 10.1016/j.apal.2017.03.005
  • Nullifying randomness and genericity using symmetric difference

    • Authors: Rutger Kuyper; Joseph S. Miller
      Abstract: Publication date: Available online 10 March 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Rutger Kuyper, Joseph S. Miller
      For a class C of sets, let us say that a set A is C stabilising if A △ X ∈ C for every X ∈ C . We prove that the Martin-Löf stabilising sets are exactly the K-trivial sets, as are the weakly 2-random stabilising sets. We also show that the 1-generic stabilising sets are exactly the computable sets.

      PubDate: 2017-03-12T16:37:07Z
      DOI: 10.1016/j.apal.2017.03.004
  • On generalized Van Benthem-type characterizations

    • Authors: Grigory K. Olkhovikov
      Abstract: Publication date: Available online 9 March 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Grigory K. Olkhovikov
      The paper continues the line of [6], [7], and [8]. This results in a model-theoretic characterization of expressive powers of arbitrary finite sets of guarded connectives of degree not exceeding 1 and regular connectives of degree 2 over the language of bounded lattices.

      PubDate: 2017-03-12T16:37:07Z
      DOI: 10.1016/j.apal.2017.03.002
  • Elementary recursive quantifier elimination based on Thom encoding and
           sign determination

    • Authors: Daniel Perrucci; Marie-Françoise Roy
      Abstract: Publication date: Available online 8 March 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Daniel Perrucci, Marie-Françoise Roy
      We describe a new quantifier elimination algorithm for real closed fields based on Thom encoding and sign determination. The complexity of this algorithm is elementary recursive and its proof of correctness is completely algebraic. In particular, the notion of connected components of semialgebraic sets is not used.

      PubDate: 2017-03-12T16:37:07Z
      DOI: 10.1016/j.apal.2017.03.001
  • Forking in short and tame abstract elementary classes

    • Authors: Will Boney; Rami Grossberg
      Abstract: Publication date: Available online 2 March 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Will Boney, Rami Grossberg
      We develop a notion of forking for Galois-types in the context of Elementary Classes (AECs). Under the hypotheses that an AEC K is tame, type-short, and failure of an order-property, we consider Definition 1 Let M 0 ≺ N be models from K and A be a set. We say that the Galois-type of A over N does not fork over M 0 , written A ⫝ M 0 N , iff for all small a ∈ A and all small N − ≺ N , we have that Galois-type of a over N − is realized in M 0 . Assuming property (E) (Existence and Extension, see Definition 3.3) we show that this non-forking is a well behaved notion of independence, in particular satisfies symmetry and uniqueness and has a corresponding U-rank. We find conditions for a universal local character, in particular derive superstability-like property from little more than categoricity in a “big cardinal”. Finally, we show that under large cardinal axioms the proofs are simpler and the non-forking is more powerful. In [10], it is established that, if this notion is an independence notion, then it is the only one.

      PubDate: 2017-03-08T09:28:37Z
      DOI: 10.1016/j.apal.2017.02.002
  • Disjoint Borel functions

    • Authors: Dan Hathaway
      Abstract: Publication date: Available online 1 March 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Dan Hathaway
      For each a ∈ ω ω , we define a Baire class one function f a : ω ω → ω ω which encodes a in a certain sense. We show that for each Borel g : ω ω → ω ω , f a ∩ g = ∅ implies a ∈ Δ 1 1 ( c ) where c is any code for g. We generalize this theorem for g in a larger pointclass Γ. Specifically, when Γ = Δ 2 1 , a ∈ L [ c ] . Also for all n ∈ ω , when Γ = Δ 3 + n 1 , a ∈ M 1 + n ( c ) .

      PubDate: 2017-03-02T08:54:36Z
      DOI: 10.1016/j.apal.2017.02.004
  • Supercompact extender based Magidor-Radin forcing

    • Authors: Carmi Merimovich
      Abstract: Publication date: Available online 28 February 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Carmi Merimovich
      The extender based Magidor-Radin forcing is being generalized to supercompact type extenders.

      PubDate: 2017-03-02T08:54:36Z
      DOI: 10.1016/j.apal.2017.02.006
  • CE-cell decomposition and open cell property in o-minimal structures

    • Authors: Somayyeh Tari
      Abstract: Publication date: Available online 28 February 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Somayyeh Tari
      Continuous extension cells, or CE-cells, are cells whose defining functions have continuous extensions on closure of their domains. An o-minimal structure has the CE-cell decomposition property if any cell decomposition has a refinement by CE-cells. If the o-minimal structure M has the CE-cell decomposition property, then it has the open cell property. In other words, every definable open set in M is a finite union of definable open cells. Here, we show that the open cell property does not imply the CE-cell decomposition property. Also, after introducing an existence of limit property, we show that the CE-cell decomposition property is equivalent to the open cell property and the existence of limit property.

      PubDate: 2017-03-02T08:54:36Z
      DOI: 10.1016/j.apal.2017.02.005
  • On non-self-referential fragments of modal logics

    • Authors: Junhua
      Abstract: Publication date: April 2017
      Source:Annals of Pure and Applied Logic, Volume 168, Issue 4
      Author(s): Junhua Yu
      Justification logics serve as “explicit” modal logics in a way that, formula ϕ is a modal theorem if and only if there is a justification theorem, called a realization of ϕ, gained by replacing modality occurrences in ϕ by (justification) terms with structures explicitly explaining their evidential contents. In justification logics, terms stand for justifications of (propositions expressed by) formulas, and as a kind of atomic terms, constants stand for that of (justification) axioms. Kuznets has shown that in order to realize (i.e., offer a realization of) some modal theorems, it is necessary to employ a self-referential constant, that is, a constant that stands for a justification of an axiom containing an occurrence of the constant itself. Based on existing works, including some of the author's, this paper treats the collection of modal theorems that are non-self-referentially realizable as a fragment (called non-self-referential fragment) of the modal logic, and verifies: (1) that fragment is not closed in general under modus ponens; and (2) that fragment is not “conservative” in general when going from a smaller modal logic to a larger one.

      PubDate: 2017-02-04T06:18:23Z
  • Polytopes and simplexes in p-adic fields

    • Authors: Luck
      Abstract: Publication date: Available online 6 January 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Luck Darnière
      We introduce topological notions of polytopes and simplexes, the latter being expected to fulfil in p-adically closed fields the function of real simplexes in the classical results of triangulation of semi-algebraic sets over real closed fields. We prove that the faces of every p-adic polytope are polytopes and that they form a rooted tree with respect to specialisation. Simplexes are then defined as polytopes whose faces tree is a chain. Our main result is a construction allowing to divide every p-adic polytope in a complex of p-adic simplexes with prescribed faces and shapes.

      PubDate: 2017-02-04T06:18:23Z
  • The ⁎-variation of the Banach–Mazur game and forcing axioms

    • Authors: Yasuo Yoshinobu
      Abstract: Publication date: Available online 6 January 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Yasuo Yoshinobu
      We introduce a property of posets which strengthens ( ω 1 + 1 ) -strategic closedness. This property is defined using a variation of the Banach–Mazur game on posets, where the first player chooses a countable set of conditions instead of a single condition at each turn. We prove PFA is preserved under any forcing over a poset with this property. As an application we reproduce a proof of Magidor's theorem about the consistency of PFA with some weak variations of the square principles. We also argue how different this property is from ( ω 1 + 1 ) -operational closedness, which we introduced in our previous work, by observing which portions of MA + ( ω 1 -closed ) are preserved or destroyed under forcing over posets with either property.

      PubDate: 2017-02-04T06:18:23Z
      DOI: 10.1016/j.apal.2017.01.003
  • On expansions of the real field by complex subgroups

    • Authors: Erin Caulfield
      Abstract: Publication date: Available online 6 January 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Erin Caulfield
      We construct a class of finite rank multiplicative subgroups of the complex numbers such that the expansion of the real field by such a group is model-theoretically well-behaved. As an application we show that a classification of expansions of the real field by cyclic multiplicative subgroups of the complex numbers due to Hieronymi does not even extend to expansions by subgroups with two generators.

      PubDate: 2017-02-04T06:18:23Z
      DOI: 10.1016/j.apal.2017.01.002
  • Unifying the model theory of first-order and second-order arithmetic via

    • Authors: Ali Enayat; Tin Lok Wong
      Abstract: Publication date: Available online 2 January 2017
      Source:Annals of Pure and Applied Logic
      Author(s): Ali Enayat, Tin Lok Wong
      We develop machinery to make the Arithmetized Completeness Theorem more effective in the study of many models of I Δ 0 + B Σ 1 + exp , including all countable ones, by passing on to the conservative extension WKL 0 ⁎ of I Δ 0 + B Σ 1 + exp . Our detailed study of the model theory of WKL 0 ⁎ leads to the simplification and improvement of many results in the model theory of Peano arithmetic and its fragments pertaining to the construction of various types of end extensions and initial segments.

      PubDate: 2017-02-04T06:18:23Z
      DOI: 10.1016/j.apal.2016.12.003
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