[[Ring theory MOC]] # Semisimple ring A [[ring]] $R$ is **semisimple** iff it meets any of the following equivalent conditions: #m/def/ring 1. $R$ is [[Semisimple module|semisimple]] as a left [[module]]; ^SS1 2. $R$ is [[Semisimple module|semisimple]] as a right [[module]]; ^SS2 3. Every $R$-[[module]] is [[Semisimple module|semisimple]]; ^SS3 4. Every [[short exact sequence]] of $R$-[[module|modules]] [[Split short exact sequence|splits]]. ^SS4 > [!missing]- Proof of equivalence > #missing/proof > Right iff left follows from [[Wedderburn–Artin theorem]]. # --- #state/develop | #lang/en | #SemBr