Timeline for Question about actions of full transformation monoids
Current License: CC BY-SA 3.0
11 events
| when toggle format | what | by | license | comment | |
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| Jan 10, 2018 at 14:30 | history | edited | Jeremy | CC BY-SA 3.0 |
added 103 characters in body
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| Jan 10, 2018 at 1:42 | vote | accept | Jeremy | ||
| Jan 10, 2018 at 1:42 | vote | accept | Jeremy | ||
| Jan 10, 2018 at 1:42 | |||||
| Jan 10, 2018 at 0:43 | comment | added | YCor | Just for people like me who generally use "transformation" for somewhat bijective stuff, "full transformation monoid on $A$" means the set of all self-maps of $A$, monoid under composition. | |
| Jan 10, 2018 at 0:16 | answer | added | Jeremy | timeline score: 2 | |
| Jan 3, 2018 at 20:05 | comment | added | Benjamin Steinberg | I expected problems like that in the infinite case. | |
| Jan 3, 2018 at 18:15 | comment | added | Jeremy | For the applications I'm interested in it's important that $A$ can be infinite. Possibly relevant: the sets of subsets of $A$ that pin down $x$ needn't be closed under arbitrary intersections. Let $A$ be infinite, let $X := \mathcal{P}(M)$, and let $mx := \{n\circ m: n\in x\}$. Consider some $a\in A$, and let $y$ be the set of all $m\in M$ that map all but finitely many members of $A$ to $a$. Then $y$ is pinned down by all co-finite subsets of $A$, but is not pinned down by the empty set. | |
| Jan 3, 2018 at 10:38 | comment | added | Benjamin Steinberg | Is A arbitrary or finite? If A is finite I have an idea for (2). | |
| Jan 2, 2018 at 21:27 | answer | added | Benjamin Steinberg | timeline score: 2 | |
| Jan 2, 2018 at 12:14 | review | First posts | |||
| Jan 2, 2018 at 12:18 | |||||
| Jan 2, 2018 at 12:12 | history | asked | Jeremy | CC BY-SA 3.0 |