Editing Lorentz transformation (section)

==Generalities==
The relations between the primed and unprimed spacetime coordinates are the '''Lorentz transformations''', each coordinate in one frame is a [[linear function]] of all the coordinates in the other frame, and the [[inverse function]]s are the inverse transformation. Depending on how the frames move relative to each other, and how they are oriented in space relative to each other, other parameters that describe direction, speed, and orientation enter the transformation equations.

{{anchor|boost}}Transformations describing relative motion with constant (uniform) velocity and without rotation of the space coordinate axes are called '''Lorentz boosts''' or simply ''boosts'', and the relative velocity between the frames is the parameter of the transformation. The other basic type of Lorentz transformation is rotation in the spatial coordinates only, these like boosts are inertial transformations since there is no relative motion, the frames are simply tilted (and not continuously rotating), and in this case quantities defining the rotation are the parameters of the transformation (e.g., [[axis–angle representation]], or [[Euler angle]]s, etc.). A combination of a rotation and boost is a ''homogeneous transformation'', which transforms the origin back to the origin.

The full Lorentz group {{math|O(3, 1)}} also contains special transformations that are neither rotations nor boosts, but rather [[Reflection (mathematics)|reflections]] in a plane through the origin. Two of these can be singled out; [[P-symmetry|spatial inversion]] in which the spatial coordinates of all events are reversed in sign and [[T-symmetry|temporal inversion]] in which the time coordinate for each event gets its sign reversed.

Boosts should not be conflated with mere displacements in spacetime; in this case, the coordinate systems are simply shifted and there is no relative motion. However, these also count as symmetries forced by special relativity since they leave the spacetime interval invariant. A combination of a rotation with a boost, followed by a shift in spacetime, is an ''inhomogeneous Lorentz transformation'', an element of the Poincaré group, which is also called the inhomogeneous Lorentz group.