full matrix ring division ring ''a'' simple algebra ''a'' full matrix algebra division algebra ''d'' ''k'' ie math n math generally ''a'' semisimple algebra finite product matrix algebras various division ''k'' algebras fact known artin wedderburn theorem fact ''a'' artinian simplifies notion jacobson radical artinian ring jacobson radical ''a'' intersection two sided maximal ideals contrast general jacobson radical
Formal science Mathematics Pure mathematics Algebra Associative algebra