Dilation

Dilation is the act of expanding something. This term is usually used in the context of "dialating the eyes".

In mathematics, a dilation is a function f from a metric space into itself that satisfies the identity

<math>d(f(x),f(y))=rd(x,y)</math>

where d(x,y) is the distance from x to y and r is some real number. A dilation of a Euclidean space is called a similarity.