• functions. They were introduced by René-Louis Baire in 1899. A Baire set is a set whose characteristic function is a Baire function. Baire functions of...
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    les fonctions de variables réelles ("On the Functions of Real Variables") in 1899. The son of a tailor, Baire was one of three children from a poor working-class...
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  • compactly supported continuous function on such a space is integrable with respect to any finite Baire measure. Every Baire set is a Borel set. The converse...
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  • shows that the Dirichlet function is a Baire class 2 function. It cannot be a Baire class 1 function because a Baire class 1 function can only be discontinuous...
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  • Measurable function: the preimage of each measurable set is measurable. Borel function: the preimage of each Borel set is a Borel set. Baire function called...
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  • is said to be a Baire space if countable unions of closed sets with empty interior also have empty interior. According to the Baire category theorem...
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  • The Baire category theorem (BCT) is an important result in general topology and functional analysis. The theorem has two forms, each of which gives sufficient...
    10 KB (1,479 words) - 19:52, 30 January 2025
  • A Baire one star function is a type of function studied in real analysis. A function f : R → R {\displaystyle f:\mathbb {R} \to \mathbb {R} } is in class...
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    The notion of upper and lower semicontinuous function was first introduced and studied by René Baire in his thesis in 1899. Assume throughout that X...
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    set. This would contradict the Baire category theorem: because the reals form a complete metric space, they form a Baire space, which cannot be meager...
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    continuous function proof of existence using Banach's contraction principle. Nowhere monotonic continuous function proof of existence using the Baire category...
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  • In set theory, the Baire space is the set of all infinite sequences of natural numbers with a certain topology, called the product topology. This space...
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  • the property of Baire and thus that no infinite parity function exists; this holds in the Solovay model, for instance. Walsh function, a continuous equivalent...
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  • In mathematics, a Baire measure is a measure on the σ-algebra of Baire sets of a topological space whose value on every compact Baire set is finite. In...
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  • René Baire, French mathematician – Baire category theorem, Baire function, Baire measure, Baire set, Baire space, Baire space, Property of Baire John...
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  • Fubini's theorem for arbitrary second countable Baire spaces. Let X and Y be second countable Baire spaces (or, in particular, Polish spaces), and let...
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  • Zermelo–Fraenkel set theory (ZF + DC + "Every subset of the real numbers has the Baire property") in which the dual of ℓ ∞ {\displaystyle \ell ^{\infty }} is ℓ...
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  • (1972). "The concept of function in the 19th and 20th centuries, in particular with regard to the discussions between Baire, Borel and Lebesgue". Archive...
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  • continuous function f from Ω to the Baire space, the preimage of A under f has the property of Baire in Ω. For every cardinal λ and every continuous function f...
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    takes each function from ω {\displaystyle \omega } to ω {\displaystyle \omega } to the characteristic function of its graph. A subset of Baire space is...
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  • sets play an important role in the formulation of the notion of Baire space and of the Baire category theorem, which is used in the proof of several fundamental...
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  • \Delta _{n}^{1}} . A subset of Baire space has a corresponding subset of Cantor space under the map that takes each function from ω {\displaystyle \omega...
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  • Lebesgue tried to prove the (correct) result that a function implicitly defined by a Baire function is Baire, but his proof incorrectly assumed that the projection...
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  • Kolmogorov–Arnold representation theorem (category Functions and mappings)
    _{i}(y)){\Big |}\in [0,6/7]} Iterating the above construction, then applying the Baire category theorem, we find that the following kind of 5-tuples are open and...
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  • uses the Baire category theorem. In calculus, part of the inverse function theorem which states that a continuously differentiable function between Euclidean...
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    least as many such functions as differentiable functions. In fact, using the Baire category theorem, one can show that continuous functions are generically...
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  • regulated function has a well-defined Riemann integral. Remark: By the Baire Category theorem the set of points of discontinuity of such function F σ {\displaystyle...
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    countably many nowhere dense sets is empty. Any open subspace of a Baire space is itself a Baire space. A continuum (pl continua) is a nonempty compact connected...
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    real numbers has the property of Baire, then BP is stronger than ¬AC, which asserts the nonexistence of any choice function on perhaps only a single set of...
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  • subsets of the Baire class, see Bourgain, Jean; Fremlin, D. H.; Talagrand, Michel (1978), "Pointwise Compact Sets of Baire-Measurable Functions", Am. J. Math...
    102 KB (17,049 words) - 16:58, 14 April 2025