Timeline for Projective modules and gradings
Current License: CC BY-SA 4.0
10 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Nov 18, 2019 at 9:08 | vote | accept | Ron | ||
| Nov 17, 2019 at 23:47 | comment | added | Chris | @WhatsUp You're right, for some reason I missed the part where also $A$ is assumed to be graded. If the grading is the trivial one (i.e. $A_0=A$) then the result is valid, but it's quite uninteresting of course. | |
| Nov 17, 2019 at 23:44 | comment | added | WhatsUp | @Chris The direct sum $M = M_{\geq d} \oplus M_{< d}$ is not a direct sum of $A$-modules. | |
| Nov 17, 2019 at 23:43 | answer | added | WhatsUp | timeline score: 2 | |
| Nov 17, 2019 at 23:25 | review | Close votes | |||
| Nov 26, 2019 at 3:05 | |||||
| Nov 17, 2019 at 23:05 | comment | added | Chris | A module is projective iff it is a direct summand of a free module. Therefore the answer to your question is yes. | |
| Nov 17, 2019 at 22:59 | history | edited | YCor | CC BY-SA 4.0 |
fixed indices
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| Nov 17, 2019 at 22:58 | history | edited | Ron | CC BY-SA 4.0 |
added 4 characters in body
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| Nov 17, 2019 at 22:47 | comment | added | Steven Landsburg | $A=k$, $M=k[x,y]$. | |
| Nov 17, 2019 at 22:39 | history | asked | Ron | CC BY-SA 4.0 |