Abstract
Based on the principle of limiting four-dimensional symmetry, we discuss coordinate transformations for constant-linear-acceleration (CLA) frames. We derive a new ''Wu transformation'' which reduces to the Lorentz transformation in the limit of zero acceleration. The time for an accelerated frame can be realized by ''computerized clocks''. A 'CLA coordinate' (w, x, y, z) is preferred for the accelerated transformation and has as much physical meaning for an accelerated frame F as (w(I), x(I), y(I), z(I)) for an inertial frame F-I. Furthermore, constant-linear-acceleration alpha must be constant increase of a particle's ''energy'' per unit length, in consistent with what has been realized in high energy linear accelerators. Some experimental implications are discussed.