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arXiv · 2305.08855

Debunking Cantor: New Set-Theoretical and Logical Considerations

Abstract

For more than a century, Cantor's theory of transfinite numbers has played a pivotal role in set theory, with ramifications that extend to many areas of mathematics. This article extends earlier findings with a fresh look at the critical facts of Cantor's theory: i) Cantor's widely renowned Diagonalization Argument (CDA) is fully refuted by a set of counter-examples that expose the fallacy of this proof. ii) The logical inconsistencies of CDA are revisited, exposing the short-comings of CDA's implementation of the method of proof by contradiction. iii) The denumerability of the power set of the set of the natural numbers, P(N), is substantiated by a proof that takes full account of all the infinite subsets of N. Such a result confirms the denumerability of the set of the real numbers, R, and with it the countable nature of the continuum. iv) Given that the denumerable character of (probably) all infinite sets makes their comparison in terms of one-to-one correspondences a rather pointless exercise, a new concept of relative cardinality is introduced which facilitates a quantitative evaluation of their different magnitudes.

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Juan A Perez. 2023-03-14. Debunking Cantor: New Set-Theoretical and Logical Considerations. https://arxiv.org/abs/2305.08855

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