Timeline for Grouplike and idempotent monoids
Current License: CC BY-SA 4.0
13 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jul 21, 2023 at 11:59 | answer | added | Emil Jeřábek | timeline score: 2 | |
| Jul 21, 2023 at 3:08 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Mar 23, 2023 at 2:02 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Nov 23, 2022 at 23:09 | comment | added | Zhen Lin | I asked a related question about rigs. The answer seems to be no. | |
| Nov 23, 2022 at 0:06 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Jul 25, 2022 at 23:06 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Jun 25, 2022 at 22:07 | answer | added | Jean-Armand Moroni | timeline score: 0 | |
| Jun 25, 2022 at 20:30 | comment | added | Jean-Armand Moroni | A good book about idempotent monoids (and other subjects), although I don't know if it answers your question: Gondran, Michel; Minoux, Michel (2008). Graphs, Dioids and Semirings: New Models and Algorithms, Springer-Verlag. | |
| Jun 25, 2022 at 15:44 | comment | added | Benjamin Steinberg | For inverse monoids the idempotents are responsible for all identifications but usually very little of the monoid embeds with the exception of the inverse hull of a group embeddable cancellative monoid | |
| Jun 25, 2022 at 15:31 | comment | added | Carl-Fredrik Nyberg Brodda | Malcev gave a necessary and sufficient condition for a cancellation monoid to embed in a group. Finding such conditions for semigroups has a long and rich history. The monoid with generators $a,b,c,d$ and two relations $ab=cd$ and $aeb=ced$ is cancellative but not group-embeddable, and of course this has no non-trivial idempotent. | |
| Jun 25, 2022 at 15:28 | comment | added | Benjamin Steinberg | Also what do you mean by grouplike part? Do you mean submonoids or maybe subsemigroups on which the group completion is injective? | |
| Jun 25, 2022 at 15:26 | comment | added | Benjamin Steinberg | What do you do about cancellative monoids that don't embed in a group? They have problems not caused by idempotents. | |
| Jun 25, 2022 at 14:23 | history | asked | Alexander Praehauser | CC BY-SA 4.0 |