Timeline for Additive, multiplicative, and Dedekind infiniteness in ${\sf (ZF)}$
Current License: CC BY-SA 4.0
8 events
| when toggle format | what | by | license | comment | |
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| May 28 at 21:52 | answer | added | Keith Kearnes | timeline score: 7 | |
| May 28 at 19:02 | comment | added | Dominic van der Zypen | @JoelDavidHamkins I also considered adding : $X$ is "+1-infinite" if there is a bijection between $X$ and $X\cup\{X\}$, so $X= X+1$ - but this is the same as Dedekind-infiniteness, I suppose | |
| May 28 at 18:57 | vote | accept | Dominic van der Zypen | ||
| May 28 at 16:27 | answer | added | Andreas Blass | timeline score: 10 | |
| May 28 at 16:02 | comment | added | Pedro Sánchez Terraf | Have you checked the Wikipedia article on finiteness? There is a reference to Levy [1958] there. | |
| May 28 at 13:55 | comment | added | Joel David Hamkins | For additively and multiplicatively, one might as well say there is a bijective map, since we have injections the other direction. So you are saying $X=X\cdot 2$ and $X^2=X$, respectively. | |
| May 28 at 11:07 | history | edited | Dominic van der Zypen | CC BY-SA 4.0 |
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| May 28 at 9:30 | history | asked | Dominic van der Zypen | CC BY-SA 4.0 |