Date: 9/04/2021 09:34:20
From: Bubblecar
ID: 1722353
Subject: Banach-Tarski Paradox

An article for those wanting to understand the joke btm posted.

Mathematician 1: “What an anagram of Banach-Tarski?”

Mathematician 2: “Banach-Tarski, Banach-Tarski.”

This is one of the classic paradoxes in modern mathematics – if we assume that, from an infinite set of sets, we can choose one element from each, then we can slice up a solid ball into finitely many pieces and reassemble it as two balls of the same size!

Banach-Tarski Paradox

Reply Quote

Date: 9/04/2021 10:18:57
From: SCIENCE
ID: 1722362
Subject: re: Banach-Tarski Paradox

someone told us that it doesn’t rely on the axiom of choice though

Reply Quote

Date: 9/04/2021 19:23:35
From: mollwollfumble
ID: 1722651
Subject: re: Banach-Tarski Paradox

Bubblecar said:


An article for those wanting to understand the joke btm posted.

Mathematician 1: “What an anagram of Banach-Tarski?”

Mathematician 2: “Banach-Tarski, Banach-Tarski.”

This is one of the classic paradoxes in modern mathematics – if we assume that, from an infinite set of sets, we can choose one element from each, then we can slice up a solid ball into finitely many pieces and reassemble it as two balls of the same size!

Banach-Tarski Paradox

I understand that joke. Excellent one !

My best references (in books) on the topic are:

References:
Robinson, R. M., On the decomposition of spheres, Fundamenta Mathematicae 34 (1947) 246-260.
Banach, S., and Tarski, A., Sur le decomposition des ensembles de points en parties respectivement congruents, Fundamenta Mathematicae 6 (1924), 244-277.

Wagon, S. (1985) The Banach-Tarski paradox, Cambridge University Press.

Richard J. Gardner & Stan Wagon (1989) At long last the circle has been squared, Notices of the American Mathematical Society, Vol. 36, No. 10, pp. 1338-1343.

Hugo Hadwiger & Han Debrunner (1964) Combinatorial Geometry in the Plane (trans. Victor Klee) Holt, Rinehart & Winston, New York

Miklós Laczkovich (1992) Paradoxical Decompositions: A Survey of Recent Results,
First European Congress of Mathemarics Volume II, Paris July 6-10, 1992 Birkhäuser pp. 159-184.

Proof complete

Reply Quote