|
In mathematics, a magma in a category, or magma object, can be defined in a category with a cartesian product. This is the 'internal' form of definition of a binary operation in a category. As Mag the magma category has direct products, the concept of an (internal) magma (or ''internal binary operation'') in Mag is defined, say Since is a morphism we must have If we want to take the original operation, this will be allowed only if the medial identity is valid. This operation, which gives a medial magma, can have a two-sided identity only if it is a commutative monoidal operation. The ''if'' direction is obvious. As a result Med, the medial category, has all its objects as '' medial objects''; and this ''characterizes'' it. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Auto magma object」の詳細全文を読む スポンサード リンク
|