Ordinal numbers | Cardinal numbers

Von Neumann cardinal assignment

The von Neumann cardinal assignment is a cardinal assignment that uses ordinal numbers. For a well-orderable set U, we define its cardinal number to be the smallest ordinal number equinumerous to U, using the von Neumann definition of an ordinal number. More precisely: where ON is the class of ordinals. This ordinal is also called the initial ordinal of the cardinal. That such an ordinal exists and is unique is guaranteed by the fact that U is well-orderable and that the class of ordinals is well-ordered, using the axiom of replacement. With the full axiom of choice, every set is well-orderable, so every set has a cardinal; we order the cardinals using the inherited ordering from the ordinal numbers. This is readily found to coincide with the ordering via ≤c. This is a well-ordering of cardinal numbers. (Wikipedia).

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From playlist Zermelo Fraenkel axioms

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The lecture was held within the framework of the Hausdorff Trimester Program : Applied and Computational Algebraic Topology

From playlist HIM Lectures: Special Program "Applied and Computational Algebraic Topology"

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If John von Neumann were on LinkedIn, his experience would include the Manhattan Project, early computer science, the atomic bomb, the hydrogen bomb, and the invention of game theory. A famed mathematician, Neumann played a major role in all of these by using applied heuristics. Add heuris

From playlist Science

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From playlist Math Major Basics

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From playlist Zermelo Fraenkel axioms

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From playlist Zermelo Fraenkel axioms

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From playlist CS2: Data Structures and Algorithms - Richard Buckland

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From playlist An Infinite Playlist

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Shmuel Weinberger: Descriptive geometry of function spaces

The lecture was held within the framework of the Hausdorff Trimester Program : Applied and Computational Algebraic Topology

From playlist HIM Lectures: Special Program "Applied and Computational Algebraic Topology"

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Lauren Ruth: "Von Neumann Equivalence"

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The Mathematical Infinity - Enrico Bombieri

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From playlist Mathematics

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The Continuum Hypothesis

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From playlist Logic

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Rolando de Santiago: "L2 cohomology and maximal rigid subalgebras of s-malleable deformations"

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From playlist HIM Lectures: Trimester Program "Universality and Homogeneity"

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From playlist HIM Lectures: Trimester Program "Periods in Number Theory, Algebraic Geometry and Physics"

Related pages

Uncountable set | Well-order | Ordinal arithmetic | Equivalence class | Class (set theory) | Countable set | Natural number | Cardinal number | Order type | Cardinal assignment | Equinumerosity | Axiom schema of replacement | Veblen function | Ordinal number | Aleph number | John von Neumann