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New Directions in Descriptive Set Theory [PDF]
§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
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Hierarchies of Effective Descriptive Set Theory [PDF]
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
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Generalized Descriptive Set Theory and Classification Theory [PDF]
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
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The descriptive set-theoretic complexity of the set of points of continuity of a multi-valued function (Extended Abstract) [PDF]
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
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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
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Topology and descriptive set theory
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Alexander S. Kechris
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The descriptive set-theoretic complexity of the set of points of continuity of a multi-valued function [PDF]
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]
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
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On the Uniform Projection Problem in Descriptive Set Theory
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
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Mixing and descriptive set theory [PDF]
A complete analytic set is defined through the concepts of invariant measure ...
Robert Kaufman
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