An active transformation is one which actually changes the physical state of a system and makes sense even in the absence of a coordinate system whereas a passive transformation is merely a change in the coordinate system of no physical significance. The distinction between active and passive transformations is one which should always be kept in mind when working with transformations. By default, by transformation, mathematicians usually mean active transformations, while physicists could mean either.
In the physical sciences, an activetransformation is one which actually changes the physical state of a system, and makes sense even in the absence of a coordinate system whereas a passive transformation is merely a change in the coordinate system of no physical significance.
The distinction between active and passive transformations is one which should always be kept in mind when working with transformations.
Thus, in order for the vector to remain unchanged by the passive transformation, the components of the vector have to transform, and according to the inverse of the transformation operator.
The Galilean transformation is used to transform between the coordinates of two reference frames which differ only by constant relative motion within the constructs of Newtonian physics.
Unlike the Galilean transformation, the relativistic Lorentz transformation can be shown to apply at all velocities so far measured, and the Galilean transformation can be regarded as a low-velocity approximation to the Lorentz transformation.
Under the Erlangen program, the space-time (no longer spacetime) of nonrelativistic physics is described by the symmetry group generated by Galilean transformations, spatial and time translations and rotations.