Four-acceleration

In special relativity, four-acceleration is a four-vector. The four-acceleration of the four-vector a is defined as the change in four-velocity over the particle's own time:

<math>{dU_a \over d\tau}.</math>

The scalar product of a four-velocity and the corresponding four-acceleration is always 0.

See also: four-vector, four-velocity, four-momentum, four-force.