The Feynman-Stueckelberg interpretation equates negative energy with negative time, but since −E = h(−ν) = h/(−t) it is better to think of this view as a mathematical statement, rather than an interpretation. What is required is to determine what negative time represents, not dismiss its existence as mere mathematics. The immediate implication is that time as it is represented in the equations of motion cannot be time in the fundamental sense. If it were, we would expect anti-matter to travel backwards in time, but we do not observe this. The mathematics of this dimension are startlingly similar to the 3 spatial dimensions, so it is reasonable to assume that this dimension is actually a 4th spatial dimension, and that it has a symmetric relationship with the flow of time. We measure time indirectly with the motion of clocks, and in the same vein, the 4th dimension has become the clock that we use in physics. Using this insight, possible solutions to both the "Arrow of Time" and the "Measurement Problem" become immediately apparent.