I heard this theory yesterday:
If something is not moving in space, then it is moving on the time axis at the speed of light.
I realize that in essence there is no object which can be considered as "not moving in space".
So my question is rather theoretical:
Given an object with zero velocity on all three axises, is it moving on the time axis at the speed of light?
Does the law of conservation of energy (or any other law in physics) imply that this condition must hold?