||Physics Essays, 2018, Vol.31 (3), pp.333-335
Clock rate in a noninertial system varies with respect to velocity and gravitational potential. Because time is linear and the variations occur simultaneously, two sets of coordinates are required to account for the separability of clock variables: one set that is velocity dependent and another due to gravitational field that is acceleration dependent. It is shown how these conditions may be satisfied mathematically with an action integral of a Lagrangian density between surfaces to describe atomic systems. Time uncertainty in inertial and noninertial systems is discussed.