Time and the Maya

My father was born in Guatemala, so I have some Mayan blood.
I am obsessed with time, the Maya were.
Here I start a few notes on this subject.
Newton says: time flows independently of everything else.
Einstein says: time depends on the mass nearby.

What does it mean?

For Newton time is absolute, for Einstein it is relative. None of them tell us what time is made of. Einstein is more precise, because he wrote equations that tell us how matter curves spacetime, and how spacetime moves matter. It is a two way street.

Here is something I thought recently.

Energy and time are intimately linked. When one eliminates time from motion equations one ends up with energy equations. It is not possible to measure time and energy with more than a given precision, because the product of the errors in these measurements is a constant (Werner Heisenberg).

Either time is constantly created or it always exists. Either way this idea is disconcerting.

Finally, time without cycles is difficult to measure. One needs a reference process that last a second say, to measure how many seconds are there in another process.

The Maya were interested in cycles that were multiples of thirteen and twenty.

I do not know why.