You quote Newton as saying:
"I. Absolute, true, and mathematical time, of itself, and from its own nature, flows equably without relation to anything external, and by another name is called duration: relative, apparent, and common time, is some sensible and external (whether accurate or unequable) measure of duration by the means of motion, which is commonly used instead of true time; such as an hour, a day, a month, a year. "
Looks to me like Newton believes in two types of time.
You say there's just the one.
You see it the way I saw it, and the way everyone today sees it. A basic, direct realism.
Here's how I see it, and we'll use Everett to get there.
Imagine you have a particle simulation, something like this:
Code:
var particles = [...] // billions of particles
var t = 0
while (true) {
t++
// do physics on the particles
}
Now, imagine the in the billions of particles in the simulation, some subset of them is acting like a clock, and another subset of them, is acting like an observer with sensory apparatus and memory to produce and store measurement records.
As the program runs,
t starts at 0 and increases by 1 every loop of the program.
Also, the observer will look at the clock and determine what time it is, based on its senses, and store a measurement record.
To Everett, that measurement record is the program's "relative state".
Basically we have the
t variable, which we can see as the programmers of the model, and then we have the time measurement records of the internal observer.
Which is absolute and relative time.
This is a mathematical formulation of Plato's world of Forms/Ideals that underlies the world apparent to our senses.
It's also a mathematical formulation of Leibniz's monadology. Or Kant's noumena.
It's consistent with the world's religious traditions, all the great philosophers, and with the metaphysics of Newton, Einstein, and Everett.
I don't expect you to agree with that. I assume most people will go to their graves with whatever metaphysics they believe today.
So, if you think that's all gibberish, and there's just one simple understandable version of time, that's fine.
I can read Newton's own words. I've made my conclusions. It required a pretty radical reconstruction of the universe in my mind. It's not a pleasant experience. Best to just ignore all this crazy talk.