Results for ' meager sets'

944 found
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  1.  96
    Strongly meager sets of size continuum.Tomek Bartoszynski & Saharon Shelah - 2003 - Archive for Mathematical Logic 42 (8):769-779.
    We will construct several models where there are no strongly meager sets of size 2ℵ0.
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  2.  38
    Strongly Meager Sets Do Not Form an Ideal.Tomek Bartoszynski & Saharon Shelah - 2001 - Journal of Mathematical Logic 1 (1):1-34.
    A set X⊆ℝ is strongly meager if for every measure zero set H, X+H ≠ℝ. Let [Formula: see text] denote the collection of strongly meager sets. We show that assuming [Formula: see text], [Formula: see text] is not an ideal.
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  3.  19
    There are no very meager sets in the model in which both the Borel Conjecture and the dual Borel Conjecture are true.Saharon Shelah & Wolfgang Wohofsky - 2016 - Mathematical Logic Quarterly 62 (4-5):434-438.
    We show that the model for the simultaneous consistency of the Borel Conjecture and the dual Borel Conjecture given in actually satisfies a stronger version of the dual Borel Conjecture: there are no uncountable very meager sets.
    No categories
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  4.  10
    Countably perfectly Meager sets.Roman Pol & Piotr Zakrzewski - 2021 - Journal of Symbolic Logic 86 (3):1214-1227.
    We study a strengthening of the notion of a perfectly meager set. We say that a subset A of a perfect Polish space X is countably perfectly meager in X, if for every sequence of perfect subsets $\{P_n: n \in \mathbb N\}$ of X, there exists an $F_\sigma $ -set F in X such that $A \subseteq F$ and $F\cap P_n$ is meager in $P_n$ for each n. We give various characterizations and examples of countably perfectly (...) sets. We prove that not every universally meager set is countably perfectly meager correcting an earlier result of Bartoszyński. (shrink)
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  5.  42
    U-Meager sets when the cofinality and the coinitiality of U are uncountable.Bosko Zivaljevic - 1991 - Journal of Symbolic Logic 56 (3):906-914.
    We prove that every countably determined set C is U-meager if and only if every internal subset A of C is U-meager, provided that the cofinality and coinitiality of the cut U are both uncountable. As a consequence we prove that for such cuts a countably determined set C which intersects every U-monad in at most countably many points is U-meager. That complements a similar result in [KL]. We also give some partial solutions to some open problems (...)
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  6.  59
    Meager sets on the hyperfinite time line.H. Jerome Keisler & Steven C. Leth - 1991 - Journal of Symbolic Logic 56 (1):71-102.
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  7.  55
    On the cofinality of the smallest covering of the real line by Meager sets.Tomek Bartoszynski & Jaime I. Ihoda - 1989 - Journal of Symbolic Logic 54 (3):828-832.
    We prove that the cofinality of the smallest covering of R by meager sets is bigger than the additivity of measure.
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  8.  34
    Saturation, Suslin trees and meager sets.Paul Larson - 2005 - Archive for Mathematical Logic 44 (5):581-595.
    We show, using a variation of Woodin’s partial order ℙ max , that it is possible to destroy the saturation of the nonstationary ideal on ω 1 by forcing with a Suslin tree. On the other hand, Suslin trees typcially preserve saturation in extensions by ℙ max variations where one does not try to arrange it otherwise. In the last section, we show that it is possible to have a nonmeager set of reals of size ℵ1, saturation of the nonstationary (...)
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  9.  24
    Strongly meager and strong measure zero sets.Tomek Bartoszyński & Saharon Shelah - 2002 - Archive for Mathematical Logic 41 (3):245-250.
    In this paper we present two consistency results concerning the existence of large strong measure zero and strongly meager sets. RID=""ID="" Mathematics Subject Classification (2000): 03e35 RID=""ID="" The first author was supported by Alexander von Humboldt Foundation and NSF grant DMS 95-05375. The second author was partially supported by Basic Research Fund, Israel Academy of Sciences, publication 658.
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  10.  31
    Meager-Additive Sets in Topological Groups.Ondřej Zindulka - 2022 - Journal of Symbolic Logic 87 (3):1046-1064.
    By the Galvin–Mycielski–Solovay theorem, a subset X of the line has Borel’s strong measure zero if and only if $M+X\neq \mathbb {R}$ for each meager set M.A set $X\subseteq \mathbb {R}$ is meager-additive if $M+X$ is meager for each meager set M. Recently a theorem on meager-additive sets that perfectly parallels the Galvin–Mycielski–Solovay theorem was proven: A set $X\subseteq \mathbb {R}$ is meager-additive if and only if it has sharp measure zero, a notion (...)
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  11.  38
    Every Sierpiński set is strongly meager.Janusz Pawlikowski - 1996 - Archive for Mathematical Logic 35 (5-6):281-285.
  12.  61
    Inscribing nonmeasurable sets.Szymon Żeberski - 2011 - Archive for Mathematical Logic 50 (3-4):423-430.
    Our main inspiration is the work in paper (Gitik and Shelah in Isr J Math 124(1):221–242, 2001). We will prove that for a partition \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathcal{A}}$$\end{document} of the real line into meager sets and for any sequence \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathcal{A}_n}$$\end{document} of subsets of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathcal{A}}$$\end{document} one can find a sequence \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} (...)
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  13.  16
    On countably perfectly meager and countably perfectly null sets.Tomasz Weiss & Piotr Zakrzewski - 2024 - Annals of Pure and Applied Logic 175 (1):103357.
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  14.  67
    Ramsey sets, the Ramsey ideal, and other classes over R.Paul Corazza - 1992 - Journal of Symbolic Logic 57 (4):1441 - 1468.
    We improve results of Marczewski, Frankiewicz, Brown, and others comparing the σ-ideals of measure zero, meager, Marczewski measure zero, and completely Ramsey null sets; in particular, we remove CH from the hypothesis of many of Brown's constructions of sets lying in some of these ideals but not in others. We improve upon work of Marczewski by constructing, without CH, a nonmeasurable Marczewski measure zero set lacking the property of Baire. We extend our analysis of σ-ideals to include (...)
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  15.  56
    Meager nowhere-dense games (IV): N-tactics.Marion Scheepers - 1994 - Journal of Symbolic Logic 59 (2):603-605.
    We consider the infinite game where player ONE chooses terms of a strictly increasing sequence of first category subsets of a space and TWO chooses nowhere dense sets. If after ω innings TWO's nowhere dense sets cover ONE's first category sets, then TWO wins. We prove a theorem which implies for the real line: If TWO has a winning strategy which depends on the most recent n moves of ONE only, then TWO has a winning strategy depending (...)
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  16.  43
    Closed measure zero sets.Tomek Bartoszynski & Saharon Shelah - 1992 - Annals of Pure and Applied Logic 58 (2):93-110.
    Bartoszynski, T. and S. Shelah, Closed measure zero sets, Annals of Pure and Applied Logic 58 93–110. We study the relationship between the σ-ideal generated by closed measure zero sets and the ideals of null and meager sets. We show that the additivity of the ideal of closed measure zero sets is not bigger than covering for category. As a consequence we get that the additivity of the ideal of closed measure zero sets is (...)
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  17.  44
    Extending Baire property by uncountably many sets.Paweł Kawa & Janusz Pawlikowski - 2010 - Journal of Symbolic Logic 75 (3):896-904.
    We show that for an uncountable κ in a suitable Cohen real model for any family {A ν } ν<κ of sets of reals there is a σ-homomorphism h from the σ-algebra generated by Borel sets and the sets A ν into the algebra of Baire subsets of 2 κ modulo meager sets such that for all Borel B, B is meager iff h(B) = 0. The proof is uniform, works also for random reals (...)
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  18.  77
    Tomek Bartoszynski. On the structure of measurable filters on a countable set. Real analysis exchange, vol. 17 no. 2 , pp. 681–701. - Tomek Bartoszynski and Saharon Shelah. Intersection of < 2ℵ0 ultrafilters may have measure zero. Archive for mathematical logic, vol. 31 , pp. 221–226. - Tomek Bartoszynski and Haim Judah. Measure and Category—filters on ω. Set theory of the continuum, edited by H. Judah, W. Just, and H. Woodin, Mathematical Sciences Research Institute publications, vol. 26, Springer-Verlag, New York, Berlin, Heidelberg, etc., 1992, pp. 175–201. - Tomek Bartoszynski, Martin Goldstern, Haim Judah, and Saharon Shelah. All meager filters may be null. Proceedings of the American Mathematical Society, vol. 117 , pp. 515–521. - Tomek Bartoszyński. Remarks on the intersection of filters. Topology and its applications, vol. 84 , pp. 139–143. [REVIEW]Claude Laflamme - 2001 - Bulletin of Symbolic Logic 7 (3):388-389.
  19.  25
    Relative Vaught's Conjecture for Some Meager Groups.Ludomir Newelski - 2007 - Notre Dame Journal of Formal Logic 48 (1):115-132.
    Assume G is a superstable locally modular group. We describe for any countable model M of Th(G) the quotient group G(M) / Gm(M). Here Gm is the modular part of G. Also, under some additional assumptions we describe G(M) / Gm(M) relative to G⁻(M). We prove Vaught's Conjecture for Th(G) relative to Gm and a finite set provided that ℳ(G) = 1 and the ring of pseudoendomorphisms of G is finite.
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  20.  47
    A base-matrix lemma for sets of rationals modulo nowhere dense sets.Jörg Brendle & Diana Carolina Montoya - 2012 - Archive for Mathematical Logic 51 (3-4):305-317.
    We study some properties of the quotient forcing notions \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${Q_{tr(I)} = \wp(2^{< \omega})/tr(i)}$$\end{document} and PI = B(2ω)/I in two special cases: when I is the σ-ideal of meager sets or the σ-ideal of null sets on 2ω. We show that the remainder forcing RI = Qtr(I)/PI is σ-closed in these cases. We also study the cardinal invariant of the continuum \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} (...)
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  21.  58
    U-lusin sets in hyperfinite time lines.Renling Jin - 1992 - Journal of Symbolic Logic 57 (2):528-533.
    In an ω1-saturated nonstandard universe a cut is an initial segment of the hyperintegers which is closed under addition. Keisler and Leth in [KL] introduced, for each given cut U, a corresponding U-topology on the hyperintegers by letting O be U-open if for any x ∈ O there is a y greater than all the elements in U such that the interval $\lbrack x - y, x + y\rbrack \subseteq O$ . Let U be a cut in a hyperfinite time (...)
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  22.  75
    A model with no magic set.Krzysztof Ciesielski & Saharon Shelah - 1999 - Journal of Symbolic Logic 64 (4):1467-1490.
    We will prove that there exists a model of ZFC+"c = ω 2 " in which every $M \subseteq \mathbb{R}$ of cardinality less than continuum c is meager, and such that for every $X \subseteq \mathbb{R}$ of cardinality c there exists a continuous function f: R → R with f[X] = [0, 1]. In particular in this model there is no magic set, i.e., a set $M \subseteq \mathbb{R}$ such that the equation f[M] = g[M] implies f = g (...)
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  23.  26
    No Tukey reduction of Lebesgue null to Silver null sets.Otmar Spinas - 2018 - Journal of Mathematical Logic 18 (2):1850011.
    We prove that consistently the Lebesgue null ideal is not Tukey reducible to the Silver null ideal. This contrasts with the situation for the meager ideal which, by a recent result of the author, Spinas [Silver trees and Cohen reals, Israel J. Math. 211 473–480] is Tukey reducible to the Silver ideal.
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  24.  26
    On completely nonmeasurable unions.Szymon Żeberski - 2007 - Mathematical Logic Quarterly 53 (1):38-42.
    Assume that there is no quasi-measurable cardinal not greater than 2ω. We show that for a c. c. c. σ -ideal [MATHEMATICAL DOUBLE-STRUCK CAPITAL I] with a Borel base of subsets of an uncountable Polish space, if [MATHEMATICAL SCRIPT CAPITAL A] is a point-finite family of subsets from [MATHEMATICAL DOUBLE-STRUCK CAPITAL I], then there is a subfamily of [MATHEMATICAL SCRIPT CAPITAL A] whose union is completely nonmeasurable, i.e. its intersection with every non-small Borel set does not belong to the σ (...)
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  25.  63
    Combinatorial properties of filters and open covers for sets of real numbers.Claude Laflamme & Marion Scheepers - 1999 - Journal of Symbolic Logic 64 (3):1243-1260.
    We analyze combinatorial properties of open covers of sets of real numbers by using filters on the natural numbers. In fact, the goal of this paper is to characterize known properties related to ω-covers of the space in terms of combinatorial properties of filters associated with these ω-covers. As an example, we show that all finite powers of a set R of real numbers have the covering property of Menger if, and only if, each filter on ω associated with (...)
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  26.  42
    The onto mapping of sierpinski and nonmeager sets.Osvaldo Guzmán González - 2017 - Journal of Symbolic Logic 82 (3).
    The principle of Sierpinski is the assertion that there is a family of functions $\left\{ {{\varphi _n}:{\omega _1} \to {\omega _1}|n \in \omega } \right\}$ such that for every $I \in {[{\omega _1}]^{{\omega _1}}}$ there is n ε ω such that ${\varphi _n}[I] = {\omega _1}$. We prove that this principle holds if there is a nonmeager set of size ω1 answering question of Arnold W. Miller. Combining our result with a theorem of Miller it then follows that is equivalent (...)
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  27.  37
    Covering properties of ideals.Marek Balcerzak, Barnabás Farkas & Szymon Gła̧b - 2013 - Archive for Mathematical Logic 52 (3-4):279-294.
    Elekes proved that any infinite-fold cover of a σ-finite measure space by a sequence of measurable sets has a subsequence with the same property such that the set of indices of this subsequence has density zero. Applying this theorem he gave a new proof for the random-indestructibility of the density zero ideal. He asked about other variants of this theorem concerning I-almost everywhere infinite-fold covers of Polish spaces where I is a σ-ideal on the space and the set of (...)
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  28. Metaphysically explanatory unification.David Mark Kovacs - 2020 - Philosophical Studies 177 (6):1659-1683.
    This paper develops and motivates a unification theory of metaphysical explanation, or as I will call it, Metaphysical Unificationism. The theory’s main inspiration is the unification account of scientific explanation, according to which explanatoriness is a holistic feature of theories that derive a large number of explananda from a meager set of explanantia, using a small number of argument patterns. In developing Metaphysical Unificationism, I will point out that it has a number of interesting consequences. The view offers a (...)
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  29.  73
    The Kunen-Miller chart (lebesgue measure, the baire property, Laver reals and preservation theorems for forcing).Haim Judah & Saharon Shelah - 1990 - Journal of Symbolic Logic 55 (3):909-927.
    In this work we give a complete answer as to the possible implications between some natural properties of Lebesgue measure and the Baire property. For this we prove general preservation theorems for forcing notions. Thus we answer a decade-old problem of J. Baumgartner and answer the last three open questions of the Kunen-Miller chart about measure and category. Explicitly, in \S1: (i) We prove that if we add a Laver real, then the old reals have outer measure one. (ii) We (...)
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  30.  20
    [Omnibus Review].Martin Goldstern - 1997 - Journal of Symbolic Logic 62 (2):680-683.
    Reviewed Works:Tomek Bartoszynski, Marion Scheepers, Set Theory, Annual Boise Extravaganza in Set Theory Conference, March 13-15, 1992, April 10-11, 1993, March 25-27, 1994, Boise State University, Boise, Idaho.R. Aharoni, A. Hajnal, E. C. Milner, Interval Covers of a Linearly Ordered Set.Eyal Amir, Haim Judah, Souslin Absoluteness, Uniformization and Regularity Properties of Projective Sets.Tomek Bartoszynski, Ireneusz Reclaw, Not Every $\gamma$-Set is Strongly Meager.Andreas Blass, Reductions Between Cardinal Characteristics of the Continuum.Claude Laflamme, Filter Games and Combinatorial Properties of Strategies.R. Daniel (...)
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  31.  27
    Answer to a question of Rosłanowski and Shelah.Márk Poór - 2021 - Journal of Mathematical Logic 21 (3):2150022.
    Rosłanowski and Shelah [Small-large subgroups of the reals, Math. Slov. 68(3) (2018) 473–484] asked whether every locally compact non-discrete group has a null but non-meager subgroup, and conversely, whether it is consistent with [Formula: see text] that in every locally compact group a meager subgroup is always null. They gave affirmative answers for both questions in the case of the Cantor group and the reals. In this paper, we give affirmative answers for the general case.
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  32.  20
    Partition reals and the consistency of t > add(R).Kyriakos Keremedis - 1993 - Mathematical Logic Quarterly 39 (1):545-550.
    We show that it is consistent with ZFC that the additivity number add of the ideal of meager sets of the real line is strictly greater than the tower number t of the reals. MSC: 03E35, 54D20.
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  33.  16
    Games Characterizing Limsup Functions and Baire Class 1 Functions.Márton Elekes, János Flesch, Viktor Kiss, Donát Nagy, Márk Poór & Arkadi Predtetchinski - 2022 - Journal of Symbolic Logic 87 (4):1459-1473.
    We consider a real-valued function f defined on the set of infinite branches X of a countably branching pruned tree T. The function f is said to be a limsup function if there is a function $u \colon T \to \mathbb {R}$ such that $f(x) = \limsup _{t \to \infty } u(x_{0},\dots,x_{t})$ for each $x \in X$. We study a game characterization of limsup functions, as well as a novel game characterization of functions of Baire class 1.
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  34.  36
    Understanding preservation theorems, II.Chaz Schlindwein - 2010 - Mathematical Logic Quarterly 56 (5):549-560.
    We present an exposition of much of Sections VI.3 and XVIII.3 from Shelah's book Proper and Improper Forcing. This covers numerous preservation theorems for countable support iterations of proper forcing, including preservation of the property “no new random reals over V ”, the property “reals of the ground model form a non-meager set”, the property “every dense open set contains a dense open set of the ground model”, and preservation theorems related to the weak bounding property, the weak ωω (...)
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  35.  24
    Turing independence and Baire category.Ashutosh Kumar & Saharon Shelah - forthcoming - Journal of Mathematical Logic.
    We show that it is relatively consistent with ZFC that there is a non-meager set of reals [Formula: see text] such that for every non-meager [Formula: see text], there exist distinct [Formula: see text] such that [Formula: see text] is computable from the Turing join of [Formula: see text] and [Formula: see text].
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  36.  18
    On the convergence of Fourier series of computable Lebesgue integrable functions.Philippe Moser - 2010 - Mathematical Logic Quarterly 56 (5):461-469.
    This paper studies how well computable functions can be approximated by their Fourier series. To this end, we equip the space of Lp-computable functions with a size notion, by introducing Lp-computable Baire categories. We show that Lp-computable Baire categories satisfy the following three basic properties. Singleton sets {f } are meager, suitable infinite unions of meager sets are meager, and the whole space of Lp-computable functions is not meager. We give an alternative characterization of (...)
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  37. On ideals of subsets of the plane and on Cohen reals.Jacek Cichoń & Janusz Pawlikowski - 1986 - Journal of Symbolic Logic 51 (3):560-569.
    Let J be any proper ideal of subsets of the real line R which contains all finite subsets of R. We define an ideal J * ∣B as follows: X ∈ J * ∣B if there exists a Borel set $B \subset R \times R$ such that $X \subset B$ and for any x ∈ R we have $\{y \in R: \langle x,y\rangle \in B\} \in \mathscr{J}$ . We show that there exists a family $\mathscr{A} \subset \mathscr{J}^\ast\mid\mathscr{B}$ of power ω (...)
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  38.  65
    Hechler reals.Grzegorz Łabędzki & Miroslav Repický - 1995 - Journal of Symbolic Logic 60 (2):444-458.
    We define a σ-ideal J D on the set of functions ω ω with the property that a real x ∈ ω ω is a Hechler real over V if and only if x omits all Borel sets in J D . In fact we define a topology D on ω ω related to Hechler forcing such that J D is the family of first category sets in D. We study cardinal invariants of the ideal J D.
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  39.  1
    On algebraic sums, trees and ideals in the Baire space.Łukasz Mazurkiewicz, Marcin Michalski, Robert Rałowski & Szymon Żeberski - forthcoming - Archive for Mathematical Logic:1-13.
    We work in the Baire space $$\mathbb {Z}^\omega $$ equipped with the coordinate-wise addition $$+$$. Consider a $$\sigma -$$ ideal $$\mathcal {I}$$ and a family $$\mathbb {T}$$ of some kind of perfect trees. We are interested in results of the form: for every $$A\in \mathcal {I}$$ and a tree $$T\in \mathbb {T}$$ there exists $$T'\in \mathbb {T}, T'\subseteq T$$ such that $$A+\underbrace{[T']+[T']+\dots +[T']}_{\text {n--times}}\in \mathcal {I}$$ for each $$n\in \omega $$. Explored tree types include perfect trees, uniformly perfect trees, Miller (...)
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  40.  18
    The Baire Closure and its Logic.G. Bezhanishvili & D. Fernández-Duque - 2024 - Journal of Symbolic Logic 89 (1):27-49.
    The Baire algebra of a topological space X is the quotient of the algebra of all subsets of X modulo the meager sets. We show that this Boolean algebra can be endowed with a natural closure operator, resulting in a closure algebra which we denote $\mathbf {Baire}(X)$. We identify the modal logic of such algebras to be the well-known system $\mathsf {S5}$, and prove soundness and strong completeness for the cases where X is crowded and either completely metrizable (...)
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  41.  19
    Lebesgue Measure Zero Modulo Ideals on the Natural Numbers.Viera Gavalová & Diego A. Mejía - forthcoming - Journal of Symbolic Logic:1-31.
    We propose a reformulation of the ideal $\mathcal {N}$ of Lebesgue measure zero sets of reals modulo an ideal J on $\omega $, which we denote by $\mathcal {N}_J$. In the same way, we reformulate the ideal $\mathcal {E}$ generated by $F_\sigma $ measure zero sets of reals modulo J, which we denote by $\mathcal {N}^*_J$. We show that these are $\sigma $ -ideals and that $\mathcal {N}_J=\mathcal {N}$ iff J has the Baire property, which in turn is (...)
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  42.  22
    A Topological Approach to Undefinability in Algebraic Extensions Of.Kirsten Eisenträger, Russell Miller, Caleb Springer & Linda Westrick - 2023 - Bulletin of Symbolic Logic 29 (4):626-655.
    For any subset $Z \subseteq {\mathbb {Q}}$, consider the set $S_Z$ of subfields $L\subseteq {\overline {\mathbb {Q}}}$ which contain a co-infinite subset $C \subseteq L$ that is universally definable in L such that $C \cap {\mathbb {Q}}=Z$. Placing a natural topology on the set ${\operatorname {Sub}({\overline {\mathbb {Q}}})}$ of subfields of ${\overline {\mathbb {Q}}}$, we show that if Z is not thin in ${\mathbb {Q}}$, then $S_Z$ is meager in ${\operatorname {Sub}({\overline {\mathbb {Q}}})}$. Here, thin and meager both (...)
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  43.  29
    Choice principles from special subsets of the real line.E. Tachtsis & K. Keremedis - 2003 - Mathematical Logic Quarterly 49 (5):444.
    We study the role the axiom of choice plays in the existence of some special subsets of ℝ and its power set ℘.
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  44.  55
    Hechler’s theorem for the null ideal.Maxim R. Burke & Masaru Kada - 2004 - Archive for Mathematical Logic 43 (5):703-722.
    We prove the following theorem: For a partially ordered set Q such that every countable subset of Q has a strict upper bound, there is a forcing notion satisfying the countable chain condition such that, in the forcing extension, there is a basis of the null ideal of the real line which is order-isomorphic to Q with respect to set-inclusion. This is a variation of Hechler’s classical result in the theory of forcing. The corresponding theorem for the meager ideal (...)
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  45.  34
    Needed reals and recursion in generic reals.Andreas Blass - 2001 - Annals of Pure and Applied Logic 109 (1-2):77-88.
    We consider sets of reals that are “adequate” in various senses, for example dominating or unbounded or splitting or non-meager. Call a real x “needed” if every adequate set contains a real in which x is recursive. We characterize the needed reals for numerous senses of “adequate.” We also consider, for various notions of forcing that add reals, the problem of characterizing the ground-model reals that are recursive in generic reals.
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  46. THIS IS NICE OF YOU. Introduction by Ben Segal.Gary Lutz - 2011 - Continent 1 (1):43-51.
    Reproduced with the kind permission of the author. Currently available in the collection I Looked Alive . © 2010 The Brooklyn Rail/Black Square Editions | ISBN 978-1934029-07-7 Originally published 2003 Four Walls Eight Windows. continent. 1.1 (2011): 43-51. Introduction Ben Segal What interests me is instigated language, language dishabituated from its ordinary doings, language startled by itself. I don't know where that sort of interest locates me, or leaves me, but a lot of the books I see in the stores (...)
     
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  47.  46
    Remarks on gaps in Dense (Q) / nwd.Teppo Kankaanpää - 2013 - Mathematical Logic Quarterly 59 (1-2):51-61.
    The structure Dense /nwd and gaps in analytic quotients of equation image have been studied in the literature 2, 3, 1. We prove that the structures Dense /nwd and equation image have gaps of type equation image, and there are no -gaps for equation image, where equation image is the additivity number of the meager ideal. We also prove the existence of -gaps in these structures. Finally we characterize the cofinality of the meager ideal equation image using families (...)
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  48.  39
    Four Neglected Prescriptions of Hartian Legal Philosophy.Kevin Toh - 2014 - Law and Philosophy 33 (6):689-724.
    This paper seeks to uncover and rationally reconstruct four theoretical prescriptions that H. L. A. Hart urged philosophers to observe and follow when investigating and theorizing about the nature of law. The four prescriptions may appear meager and insignificant when each is seen in isolation, but together as an inter-connected set they have substantial implications. In effect, they constitute a central part of Hart's campaign to put philosophical investigations about the nature of law onto a path to a genuine (...)
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  49. (1 other version)The roots of reference.W. V. Quine - 1973 - LaSalle, Ill.,: Open Court.
    Our only channel of information about the world is the impact of external forces on our sensory surfaces. So says science itself. There is no clairvoyance. How, then, can we have parlayed this meager sensory input into a full-blown scientific theory of the world? This is itself a scientific question. The pursuit of it, with free use of scientific theory, is what I call naturalized epistemology. The Roots of Reference falls within that domain. Its more specific concern, within that (...)
     
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  50.  36
    Erratum to: Four Neglected Prescriptions of Hartian Legal Philosophy.Kevin Toh - 2015 - Law and Philosophy 34 (3):333-368.
    This paper seeks to uncover and rationally reconstruct four theoretical prescriptions that H. L. A. Hart urged philosophers to observe and follow when investigating and theorizing about the nature of law. The four prescriptions may appear meager and insignificant when each is seen in isolation, but together as an inter-connected set they have substantial implications. In effect, they constitute a central part of Hart’s campaign to put philosophical investigations about the nature of law onto a path to a genuine (...)
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