In
physics and
engineering, an
active transformation, or
alibi transformation, is a
transformation which actually changes the physical position of a point, or
rigid body, which can be defined even in the absence of a
coordinate system; whereas a
passive transformation, or
alias transformation, is merely a change in the coordinate system in which the object is described (change of coordinate map, or
change of basis). By default, by
transformation,
mathematicians usually refer to active transformations, while
physicists and
engineers could mean either.