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Hi again,Sorry, I should not have brought any of this up. It does not add much to my initial issue.I think this is outside of the scope of Galilean relativity because nothing is actually moving in GR. GR implies a block universe.I'm easily confused. GR is usually an abbreviation of "General Relativity" but I'm going to assume you are using it as an abbreviation of Galilean Relativity.
I'm not really sure that Galilean Relativity does fully demand the idea of a block universe. I think we usually forumlate the notion of a block universe after we accept Special Relativity. However, the fine details about what a "block universe" means may not be all that important. Just simple Newtonian mechanics already suggests something we would call a "deterministic universe". This just means that, if Newtonian mechanics is correct, then you should be able to calculate where everything will be and how it is moving at any time in the future from knowledge about where it is and how it is moving now. Similarly, you should also be able to calculate where it was and how it was moving at any point in the past from knowledge about the present. Overall then, if you had knowledge about the present than it's just a matter of doing some calculations - there's nothing uncertain about the future or past, you would have full knowledge of that.
A deterministic universe doesn't necessarily mean that the future has already happened, just that that there's nothing especially uncertain or undetermined about it.
Special Relativity (SR) probably pushes the notion of a deterministic universe a bit further. One of the things a good text or lecture course about SR might discuss is the example of what is called the "Andromeda paradox" or Rietdijk–Putnam–Penrose argument ( https://en.wikipedia.org/wiki/Rietdijk%E2%80%93Putnam_argument ). These sorts of topics are one of the ways in which you could build up to a more complete notion of a block universe. Specifically, where you could start to argue that all instants of time and space seem to need to exist. It's worth mentioning that although these things often have names like "paradox" it's just because Physicist's and Philosopher's have good publicity and media agents and they select the titles. They aren't usually impossible or logical paradoxes, it's just that it sounds more interesting to call it a "paradox" instead of "an intersting thing".
Additionally, it's not entirely fair to say that the idea of a "Block Universe" is an idea in Physics. It's an idea in Philosophy that is based on some ideas in Physics, although they often call it "Eternalism". Physics doesn't really care if you favour a Block universe or Presentism, it just offers some models and allows some predictions to be made. It's not offering any fundamental truth about how the universe really is, only a few models that seem to be useful. More to the point, you can easily reconcile Special Relativity with Presentism if you try. One option is to accept that when an object experiences an acceleration than the universe around them is changed.
(Please don't get too worried about ideas like a deterministic universe - there's loads of things in physics that can offset or alleviate any concerns, like Chaos theory and quantum uncertainty but that falls outside the scope of this thread).
I am currently watching the videos that you posted from Leonard Susskind. Maybe this will help me.So the idea of an object to be moving relative to another object doesn't really make any sense in a block universe.Are you sure? Movement is described just as a rate of change of one thing (position) with respect to something else (time). So this is just a ratio of a small change in one variable to the corresponding small change in another variable. Just because we, human beings, tend to experience and think of time a certain way, doesn't necessarily grant it any special nature. It's just something, some variable, we can use to calculate rates of change with respect to. We could have some other variable like S - let's give it a silly name like "entropy of the universe" - and just calculate rates of change of position with respect to S.