Timeline for What is Barr-Beck?
Current License: CC BY-SA 4.0
7 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Oct 7, 2021 at 14:29 | comment | added | Tom Leinster | Mac Lane's attribution of CTT to Barr as well as Beck appears to be incorrect. Thanks to @varkor, we can now all see Beck's original 1966 manuscript. CTT appears there, under the name CTT and in exactly the form Mac Lane states it. So why did Mac Lane add Barr's name? He doesn't say. There's no monadicity theorem in either of the works by Barr in Mac Lane's bibliography. So I know of no justification for using Barr's name or calling the theorem "Barr-Beck". | |
| Feb 17, 2021 at 19:18 | vote | accept | Friedrich Knop | ||
| Feb 17, 2021 at 19:18 | comment | added | Friedrich Knop | Thanks! So Barr contributed to Becks's theorem after all by making it more manageable. | |
| Feb 17, 2021 at 18:39 | comment | added | Alexander Campbell | I wonder that too. I asked Ross Street about this once but he said it was before his time! | |
| Feb 17, 2021 at 18:33 | comment | added | Tim Campion | I wonder if Mac Lane's attribution of CTT to Barr-Beck has a similar backstory living outside of published references? Somebody should probably ask Michael Barr. He used to be on MO occasionally, but apparently he hasn't been on in some years. | |
| Feb 17, 2021 at 18:28 | comment | added | Alexander Campbell | Incidentally, the precise form of Beck's monadicity theorem does not appear in Beck's thesis, and I don't think he published it anywhere else. Only a weaker form (again, giving sufficient but not necessary conditions) appears in the thesis. According to Mac Lane (in the Notes at the end of Chapter VI), Beck presented the precise form at a conference in 1966. | |
| Feb 17, 2021 at 18:25 | history | answered | Alexander Campbell | CC BY-SA 4.0 |