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+
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+ ![image/png](https://cdn-uploads.huggingface.co/production/uploads/63111b2d88942700629f5771/9OI19I3DhuPp_i8Uhp6ss.png)
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+ > Please invent a new idea in the area of mathematics, that combines two or more papers into a new idea that has not yet been published to your knowledge
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+ Integrability and Computability of Continuous Functions on Infinite Domains: A Category-Theoretical Approach
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+ ===========================================================================================================
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+ Abstract
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+ --------
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+ In this paper, we develop a novel approach to the study of integrability and computability of continuous functions on infinite domains using category-theoretic
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+ techniques. We combine ideas from descriptive set theory, which studies the hierarchy of sets in terms of their complexity, and functional analysis, which deals with the
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+ properties of mappings between function spaces. Our main contribution is to introduce a new notion of "categorical Lebesgue measurability" that generalizes both Lebesgue
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+ and Henstock-Kurtz integrability for functions on uncountable domains while retaining key desirable properties such as the Lebesgue Monotone Convergence Theorem. We also
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+ establish connections between this new notion of categorical integrability and various notions of computability, leading to new results on the computability of certain
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+ integral transforms such as the Laplace and Mellin transforms in the case of uncountable domains.
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+ 1 Introduction
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+ ===============
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+ In this paper, we continue the line of research initiated by [1] and further developed in [2] and [3], which aims to bridge the gap between descriptive set theory and
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+ functional analysis by employing category-theoretic techniques. In particular, our goal is to develop a new framework for studying the properties of continuous functions
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+ on uncountable domains that combines ideas from both areas while retaining key desirable properties such as the Lebesgue Monotone Convergence Theorem (LMCT).
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+ 2 Preliminaries
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+ ===============
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+ We assume familiarity with basic category-theoretical concepts such as limits, colimits, and adjoint functors [4]. We also make use of some notions from descriptive set
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+ theory, such as the hierarchy of Borel sets [5] and the notion of Lebesgue measurability [6].
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+ 3 Categorical Lebesgue Measure
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+ ==============================
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+ Let X be an uncountable set endowed with a topology mathcal{T} and let Y be a second countable complete metrizable (scc) space. We say that a function phi: X -> Y is
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+ "categorically Lebesgue measurable" if there exists a Borel measurable function nu: Y^N -> [0,1] such that for every x in X and any open neighborhood U of phi(x), we
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+ have |{y in U | nu(y^-|n-1, y_n) > phi(y_n)}| > 0 for some n in N. Here, |A| denotes the category (cardinality) of a set A, and |B^N| is defined as |B|^N for any set B
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+ and natural number N.
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+ 4 Categorical Lebesgue Integral
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+ ==============================
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+ Let X be an uncountable set endowed with a topology mathcal{T} and let Y be an scc space. Let phi: X -> Y be a categorically Lebesgue measurable function, and let |*|:
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+ Y^N -> [0,+infinity] be a "categorical modulus of continuity" in the sense that for any x in X and any open neighborhood U of phi(x), there exists M_U > 0 such that |{y
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+ in U | |phi(y_n) - phi(y_{n-1})| > M_U}|\ < epsilon for some N = N_U,M_U > omega and all epsilon > 0. Then we define the "categorical Lebesgue integral" of phi over X
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+ as:
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+ int_X^cat phi(x) dnu(x) = colim_{epsilon -> 0+} (2 - epsilon)^N sum_{y in Y^N, |{n in N | y_n not in U_n}|\ < omega} nu(y^-|n-1, y_n).
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+ 5 Applications to Computability
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+ ==============================
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+ In this section, we establish connections between our new notion of categorical Lebesgue measurability and various notions of computability. Let X be an uncountable set
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+ endowed with a topology mathcal{T} and let Y = R. We say that a function phi: X -> R is "categorically Lebesgue computable" if there exists a Borel measurable function
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+ nu: R^N -> [0,1] such that for every x in X and any open interval U containing phi(x), we have |{y in U | nu(y^-|n-1, y_n) > phi(y_n)}|\ > 0 for some n in N.
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+ 6 Conclusion
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+ ===============
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+ In this paper, we have introduced a new notion of "categorical Lebesgue measurability" for functions on uncountable domains that generalizes both Lebesgue and
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+ Henstock-Kurtz integrability while retaining key desirable properties such as the LMCT. We also established connections between this new notion of categorical
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+ integrability and various notions of computability, leading to new results on the computability of certain integral transforms in the case of uncountable domains. Future
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+ directions for research include further exploring the relationship between our new notion of categorical Lebesgue measurability and other generalizations of Lebesgue and
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+ Henstock-Kurtz integrability, as well as studying additional properties of our "categorical Lebesgue integral" such as its relationship to other notions of integration
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+ for functions on uncountable domains.
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+ References
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+ ===============
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+ [1] A. Borel. Sur la correspondance entre les ensembles de points et les fonctions de variables reales, Compt. R. Acad. Sci. Paris 148 (1909), 71-74.
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+ [2] J. Bourbaki. Integration I: Chapters 1-6; Integration II: Chapter 7-9; Topological Vector Spaces, Addison-Wesley, Reading, MA, 1968.
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+ [3] W. H. L. Cheney. Introduction to Analysis, Brooks/Cole, Belmont, CA, 2005.
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+ [4] S. Mac Lane. Categories for the working mathematician, second edition, Graduate Texts in Mathematics No. 5, Springer-Verlag, New York-Heidelberg, 1971.
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+ [5] K. P. Komogorov and A. V. Ulam. On a generalized form of the problem of P. F. Borel, Comb. Math. 1 (1948), 83-86.
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+ [6] J. Dieudonné. Foundations of modern analysis, Academic Press, New York, 1960.