List questions from group-rings | MathQa

Show $D = \delta_1 +\cdots+ \delta_m$ is in the center of the group ring $RG$ .

Published on 31 Dec 2024 - 14:41

Projective but not free module over groupring

Published on 12 Jan 2025 - 10:06

Is it true that $(R\times S)[G]\cong R[G]\times S[G]$?

Published on 13 Jan 2025 - 2:10

Express $[RG,RG]$ as $R-$ linear span of $[g,h]$

Published on 30 Dec 2024 - 11:52

What is the augmentation ideal of $\Bbb{Z}S_3$

Published on 30 Dec 2024 - 14:50

If $H\leq G$ and $|H|$ is invertible in a ring $R$, why does $RG/H\simeq e_HRG$?

Published on 31 Dec 2024 - 8:44

Conditions for free/projective/flat module over a groupring

Published on 18 Dec 2024 - 23:02

How do I view $k$ as $kG$-module?

Published on 12 Jan 2025 - 18:18

Difference between $\mathbb{Z} G$-module and $G$-module

Published on 02 Jan 2025 - 0:20

Equivalent condition for normalizer problem

Published on 31 Dec 2024 - 13:12