Dear professor Christian Corda:
The only things about of which I wrote, are the positive ones, my find is of not use for me, practically its only use are for theoretical physicists. I make it really short, about the subject can be written thousands pages, but this is the nut of it, this are the things were everybody get confuse and confuse everybody else. You know people think that because for two thousand years the problem of "time" was not solve, can't be solve, this is not true as you can see here.
Anthropologist tell us men measured "time" since 30.000 years ago basically recording celestial bodies "constant" "motion" which was used as a system of measurement by people, for practical daily uses, as agriculture, hunting seasons, commerce.
Civilizations learn from primitive men its use, but with it, acquired the incognita of what they were measuring?, that now days we call the experimental meaning of "time", since their beginnings they ask themselves for that and still do, but in that epoch, they were especially interested in better and more precise ways of measurement.
Long 20.000 years after, science began a very slow beginning and as part of natural science was born a primitive physics no more than 2000 years ago, since the beginning physics included "time" a basic part, a foundational one, during those millenniums there was curiosity about its meaning but not a serious need to know the experimental one. The real need for physics was to improve precision of measurement.
All the above is the most probable.
Now on there is no hypothesis it is only an explanation using only proved facts.
Centuries old proved facts, like earth rotation and its consequence the day, also a prove of an earth complete rotation of "constant" "motion", which last from one sunrise to the next one.
This period of "constant" "motion" the day, it was divided in equal parts in 24 equal hours by Egyptians, the hour in 60 equal minutes and the minute in 60 equal seconds by Sumerians.
If "motion" does not have those characteristics, still could be a variable but can't be divided in equal parts, so can't be use to measure any other "motion".
For practical reasons men copy the "constant" "uniform" celestial bodies "motion" designing clocks. When the hour hand rotate twice around the clock dial, it represents an earth complete "constant" "uniform" rotation "motion".
Looking at the clock dial we will know at what hour of the day we are which is the same that knowing, on what part of the earth complete "constant" rotation "motion" we are.
With the clock dial hands "constant" "motion", representing earth rotation motion, comparatively we measure all "no constant" "motions" which are part of every change or transformation occurring to us, or everything around us.
The real definition of Duration: Is the period of change or transformation allowed by "motion" and limited by men.
Change, transformation and motion, none of the concepts can exist without the other two.
Above it is proved that what theoretical physicists needed for the last 50 years, the experimental meaning of "time" it is "motion".
That with a "constant" "uniform", "regular" "motion" we measure all the rest of "motions" without those characteristics.
Also it is proved that "motion" is a quality or property of every physical existing thing, and as such can relate to every physical existing thing.
Within those "motion" can be affected and affect, gravity, inertia, mass
Etc. etc..............
Héctor