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New Directions in Descriptive Set Theory [PDF]

open access: greenBulletin of Symbolic Logic, 1999
§1. I will start with a quick definition of descriptive set theory: It is the study of the structure of definable sets and functions in separable completely metrizable spaces. Such spaces are usually calledPolish spaces. Typical examples are ℝn, ℂn, (separable) Hilbert space and more generally all separable Banach spaces, theCantor space2ℕ, theBaire ...
Alexander S. Kechris
core   +11 more sources

Hierarchies of Effective Descriptive Set Theory [PDF]

open access: bronzeTransactions of the American Mathematical Society, 1969
1. Introduction and summary. The theory of hierarchies deals with the classification of objects according to some measure of their complexity. Such classifications have been fruitful in several areas of mathematics: analysis (descriptive set theory), recursion theory, and the theory of models.
Peter G. Hinman
  +6 more sources

Generalized Descriptive Set Theory and Classification Theory [PDF]

open access: yesMemoirs of the American Mathematical Society, 2010
Descriptive set theory is mainly concerned with studying subsets of the space of all countable binary sequences. In this paper we study the generalization where countable is replaced by uncountable. We explore properties of generalized Baire and Cantor spaces, equivalence relations and their Borel reducibility.
Friedman, Sy D.   +2 more
core   +9 more sources

The descriptive set-theoretic complexity of the set of points of continuity of a multi-valued function (Extended Abstract) [PDF]

open access: yesElectronic Proceedings in Theoretical Computer Science, 2010
In this article we treat a notion of continuity for a multi-valued function F and we compute the descriptive set-theoretic complexity of the set of all x for which F is continuous at x.
Vassilios Gregoriades
doaj   +4 more sources

On the Uniform Projection and Covering Problems in Descriptive Set Theory Under the Axiom of Constructibility

open access: greenMathematics
The following two consequences of the axiom of constructibility V=L will be established for every n≥3: 1. Every linear Σn1 set is the projection of a uniform planar Πn−11 set. 2.
Vladimir Kanovei, Vassily Lyubetsky
doaj   +3 more sources

Topology and descriptive set theory

open access: bronzeTopology and its Applications, 1994
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Alexander S. Kechris
openaire   +5 more sources

The descriptive set-theoretic complexity of the set of points of continuity of a multi-valued function [PDF]

open access: yesLogical Methods in Computer Science, 2011
In this article we treat a notion of continuity for a multi-valued function $F$ and we compute the descriptive set-theoretic complexity of the set of all $x$ for which $F$ is continuous at $x$.
Vassilios Gregoriades
doaj   +3 more sources

Descriptive set Theory of Families of Small Sets [PDF]

open access: greenBulletin of Symbolic Logic, 2007
AbstractThis is a survey paper on the descriptive set theory of hereditary families of closed sets in Polish spaces. Most of the paper is devoted to ideals and σ-ideals of closed or compact sets.
Matheron, Étienne, Zelený, Miroslav
openaire   +4 more sources

On the Uniform Projection Problem in Descriptive Set Theory

open access: goldAxioms
For every n≥1, generic models of ZFC will be presented for either of the following two sentences: 1. There exists a linear Σn+21 set not equal to the projection of any uniform planar Πn+21 set. 2.
Vladimir Kanovei, Vassily Lyubetsky
doaj   +2 more sources

Mixing and descriptive set theory [PDF]

open access: bronzeIllinois Journal of Mathematics, 2006
A complete analytic set is defined through the concepts of invariant measure ...
Robert Kaufman
openaire   +3 more sources

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