Dichromatic symmetry
Two-colour symmetry (examples, history and dimensional counts) / From Wikipedia, the free encyclopedia
Dichromatic symmetry,[1] also referred to as antisymmetry,[2][3] black-and-white symmetry,[4] magnetic symmetry,[5] counterchange symmetry[6] or dichroic symmetry,[7] is a symmetry operation which reverses an object to its opposite.[8] A more precise definition is "operations of antisymmetry transform objects possessing two possible values of a given property from one value to the other."[9] Dichromatic symmetry refers specifically to two-coloured symmetry; this can be extended to three or more colours in which case it is termed polychromatic symmetry.[10] A general term for dichromatic and polychromatic symmetry is simply colour symmetry. Dichromatic symmetry is used to describe magnetic crystals and in other areas of physics,[11] such as time reversal,[12] which require two-valued symmetry operations.
![Thumb image](http://upload.wikimedia.org/wikipedia/commons/1/10/Dichromatic_triangle.jpg)