Bobzills;
Just as you know that you do not keep correct time and look for some method that is better at keeping time it is necessary to look for a clock or a method that agrees with reality.
Since it is obvious that clocks do not always agree with the reality of past, present, or future (real time) we can look for a clock or method of knowing real time.
All clocks that we know about are tied to some physical function and are therefore affected by physical changes. We may thank Einstein for giving us the answer. The Special Theory of Relativity gives us the relation of clock rate to velocity. All clocks will tick the fastest at zero velocity and decrease with velocity.
We may use zero velocity as a measure of real time that will have universal agreement and calculate any condition to zero velocity to get real time.
