Abstract

Though Einstein explained time dilation without recourse to a universal frame of reference, he erred by abolishing universal present moments. Relative simultaneity is insufficiently relativistic insofar as it depends on the absolute equality of reference frames in the measurement of the timing of events. Yet any given set of events privileges the frame in which the events take place. Relative to those events, the privileged frame yields the correct measurement of their timing while all other frames yield an incorrect measurement. Instead of multiple frames occupying multiple times, one frame is correct and all others incorrect within a shared present moment. With the collapse of relative simultaneity, we may regard time as a succession of universal moments. Absolute simultaneity, in turn, explains why an accelerated inertial frame dilates in time rather than regressing to a prior moment relative to non-accelerated frames. In the context of flowing time, absolute simultaneity predicts time dilation while relative simultaneity predicts time regression. Einstein's explanation of time dilation is therefore incomplete.