Timeline for What are some examples of ingenious, unexpected constructions?
Current License: CC BY-SA 3.0
5 events
| when toggle format | what | by | license | comment | |
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| Dec 22, 2018 at 21:17 | comment | added | Forever Mozart | It's every bit as valid as the 1000's of fundamental theorems that require Axiom of Choice. In ZF, Banach-Tarski equivalent to the statement that, for instance, every separable metric connected space has $|\mathbb R|$ points. The latter is 100% obvious. So yes, BT is surprising. | |
| Aug 25, 2012 at 4:00 | comment | added | Todd Trimble | Maybe, but it'd have to be considered a non-constructive construction. | |
| Mar 16, 2012 at 14:46 | comment | added | Tom Leinster | I'd say so: they constructed an isomorphism (in a suitable sense) between a unit ball and the disjoint union of two unit balls. | |
| Mar 14, 2012 at 15:56 | comment | added | Margaret Friedland | Yes, but does it qualify as a construction? | |
| Mar 12, 2012 at 16:54 | history | answered | Barry Cipra | CC BY-SA 3.0 |