Diagrams named for this property are studied in (*) category theory.
Cohen-Macaulay rings are noetherian local rings with this property with Krull dimension equal to their depth, and only rings with this property have a single nilradical. Diagrams named for this property are studied in (*) category theory. Groups whose product has this property are called abelian. This property does not hold for matrix multiplication or for subtraction. For 10 points, name this property of an operation such that the order of the operands does not change the result, which holds for addition because x plus y equals y plus x.
Cohen-Macaulay rings are noetherian local rings with this property with Krull dimension equal to their depth, and only rings with this property have a single nilradical.
{commutativity}