Timeline for Can Ext over a group ring always be expressed as group cohomology ?
Current License: CC BY-SA 3.0
6 events
when toggle format | what | by | license | comment | |
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Dec 21, 2012 at 13:43 | comment | added | Ralph | Yes. The augmentation is given by $RG \to R,\;g \mapsto 1$ and $RG=\bigoplus_g Rg$ is $R$-free. | |
Dec 21, 2012 at 13:25 | comment | added | Marc Palm | I meant to say, eg RG is such an algebra? mathoverflow.net/questions/674/… | |
Dec 21, 2012 at 12:02 | comment | added | Ralph | Marc, I'm not sure what you mean by this equality. | |
Dec 21, 2012 at 11:46 | comment | added | Marc Palm | augmented R-projective R-algebra A = group ring RG? | |
Dec 21, 2012 at 9:10 | vote | accept | Mark Opitz | ||
Dec 21, 2012 at 0:16 | history | answered | Ralph | CC BY-SA 3.0 |