In mathematics, the first uncountable ordinal, traditionally denoted by ω 1 {\displaystyle \omega _{1}} or sometimes by Ω {\displaystyle \Omega } , is...
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In set theory, an ordinal number, or ordinal, is a generalization of ordinal numerals (first, second, nth, etc.) aimed to extend enumeration to infinite...
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below the first uncountable ordinal ω1; their supremum is called Church–Kleene ω1 or ωCK 1 (not to be confused with the first uncountable ordinal, ω1), described...
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one means. Aleph number Beth number First uncountable ordinal Injective function Weisstein, Eric W. "Uncountably Infinite". mathworld.wolfram.com. Retrieved...
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topology on an algebraic variety over an uncountable field is not first-countable. Another counterexample is the ordinal space ω 1 + 1 = [ 0 , ω 1 ] {\displaystyle...
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countable ordinals, and thus the first ordinal at which all the Borel sets are obtained is ω 1 {\displaystyle \omega _{1}} , the first uncountable ordinal. The...
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produce countable ordinals even for uncountable arguments, and some of which are "collapsing functions". The small Veblen ordinal θ Ω ω ( 0 ) {\displaystyle...
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for any given ordinal notation there will be ordinals below ω1 (the first uncountable ordinal) that are not expressible. Such ordinals are known as large...
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\omega _{1}} , the first uncountable ordinal, which is the set of all countable ordinals, analogously to how the Church-Kleene ordinal is the set of all...
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naming all ordinals less than the Church–Kleene ordinal, which is a countable ordinal. Beyond the countable, the first uncountable ordinal is usually...
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Ω = ω1 is the first uncountable ordinal. εΩ+1 is the first epsilon number after Ω = εΩ. ψ(α) is defined to be the smallest ordinal that cannot be constructed...
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produce countable ordinals even for uncountable arguments, and some of which are ordinal collapsing functions. The large Veblen ordinal is sometimes denoted...
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In mathematics, the Feferman–Schütte ordinal (Γ0) is a large countable ordinal. It is the proof-theoretic ordinal of several mathematical theories, such...
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Enumeration (section Countable vs. uncountable)
to encompass transfinite listings. Under this definition, the first uncountable ordinal ω 1 {\displaystyle \omega _{1}} can be enumerated by the identity...
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behavior of functions. Chaitin's constant. In set theory, the first uncountable ordinal number, ω1 or Ω The absolute infinite proposed by Georg Cantor...
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{\displaystyle \omega } is the first infinite ordinal and ω 1 {\displaystyle \omega _{1}} the first uncountable ordinal. The deleted Tychonoff plank is...
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it is sequentially compact if and only if it is compact. The first uncountable ordinal with the order topology is an example of a sequentially compact...
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{\displaystyle \Omega } stand for the first uncountable ordinal ω 1 {\displaystyle \omega _{1}} , or, in fact, any ordinal which is an ε {\displaystyle \varepsilon...
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Cardinality of the continuum (redirect from Lebesgue measure argument for uncountability of the reals)
_{\omega _{1}}} , where ω 1 {\displaystyle \omega _{1}} is the first uncountable ordinal, so it could be either a successor cardinal or a limit cardinal...
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counted with multiplicity the density parameter in cosmology the first uncountable ordinal (also written as ω1) Chaitin's constant for a given computer program...
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mathematics, ψ0(Ωω), widely known as Buchholz's ordinal[citation needed], is a large countable ordinal that is used to measure the proof-theoretic strength...
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not be unique. For example, let X be the set of ordinals at most equal to the first uncountable ordinal Ω, with the topology generated by "open intervals"...
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Separable space (section First examples)
{\displaystyle \triangle } being the symmetric difference operator). The first uncountable ordinal ω 1 {\displaystyle \omega _{1}} , equipped with its natural order...
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Club set (category Ordinal numbers)
club set with respect to the first uncountable ordinal; but it is not a club set with respect to any higher limit ordinal, since it is neither closed nor...
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Order topology (redirect from Ordinal space)
interest is the case when λ = ω1, the set of all countable ordinals, and the first uncountable ordinal. The element ω1 is a limit point of the subset [0,ω1)...
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0 ) {\displaystyle \varphi (1,0,0,0)} , where Ω is the smallest uncountable ordinal. Ackermann's system of notation is weaker than the system introduced...
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rationals. T is uncountable as it has a non-empty level Uα for each countable ordinal α which make up the first uncountable ordinal. This proves that...
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Epsilon number (category Ordinal numbers)
The ordinal ε0 is still countable, as is any epsilon number whose index is countable. Uncountable ordinals also exist, along with uncountable epsilon...
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since it is not locally finite. The space of ordinals at most equal to Ω, the first uncountable ordinal with the order topology is a compact topological...
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Cardinality (section Uncountable sets)
(all ordinals α {\displaystyle \alpha } with cardinality | α | ≤ ℵ 0 {\displaystyle |\alpha |\leq \aleph _{0}} ), the first uncountable ordinal. Since...
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