[omarchowdhury]

I fail to see how "right now, over there" fails to have any meaning when at this very moment that point in space does exist, the assumption is that we are moving between there and here without any lag (instantly) when comparing the sets of areas.

In our minds, where the comparison is taking place, we need not account for how long it takes light to travel. We can simultaneously hold the thought that we are here on Earth, and way over there, there once was a giant cloud of water vapor.

[Cushman]

First you should read the Wiki article I linked, since it goes over it much more thoroughly than I can, and then maybe I can help if you still have questions. Here's the introductory paragraph to get you started:

Where an event occurs in a single place–for example, a car crash–all observers will agree that both cars arrived at the point of impact at the same time. But where the events are separated in space, such as one car crash in London and another in New York, the question of whether the events are simultaneous is relative: in some reference frames the two accidents may happen at the same time, in others (in a different state of motion relative to the events) the crash in London may occur first, and in still others the New York crash may occur first.

I emphasize again that this is the actual way the universe works, not theoretical physics. What you say about our brains holding the two ideas simultaneously in our head is true; our brains are wrong, and the statement "There once was a giant cloud of water vapor" is untrue, or rather, undefined.

Also: I fail to see how "right now, over there" fails to have any meaning when at this very moment that point in space does exist, the assumption is that we are moving between there and here without any lag (instantly) when comparing the sets of areas.

To move "instantly" from one place to another presupposes there is such a thing as "over there, right now", which there isn't. Your definition thus has no meaning. Isn't this stuff wild?

[omarchowdhury]

So what I take that relativity of simultaneity is showing, is that there is no "universal time" everywhere.

But this is all dependent on the positioning of the observers. The observers painted on the universal graph are all ones waiting for light to reach them. This is what is causing the confusion as to when is "now", as all the observers or points of awareness are separated in space. And I take it that, their separation in space is also what separates them in time... and thus each have different notions of when now is.

But can we not conjure an omniscient observer as our frame of reference? One who exists at all points, at all times.

Would he not be able to observe both the Earth on July 24, 2011 and what exists in the space of the water vapor cloud as Earth time is still July 24, 2011?

[Dylan16807]

Sure you can.

Pick a vector.

Any vector.

You can create an observer moving at this velocity and it'll give you a different idea of simultaneous from an omniobserver at a different vector.

Oh, and before you ask, no there is no 'unmoving' vector. They're all relative to each other with no reference frame.

[Cushman]

But can we not conjure an omniscient observer as our frame of reference?

Yes. We can not. In fact, that is precisely what the theory of relativity states: There is no privileged reference frame.

There is literally, actually no such thing as "what exists in the space of the water vapor cloud as Earth time is still July 24, 2011". As I look at my clock at noon on July 24, I see water. Someone at the reservoir will not see my clock strike noon for twelve billion years, my time, and they'll look around and maybe see no water. We disagree, but we're both right in our own frame of reference. Both perspectives are true.

Which makes sense if you think about it; your omniscient observer would have to agree with one or the other (or some other) disagreeing perspective. What criteria could you possibly use to choose between them?

[sliverstorm]

Tip: "I'd love to explain it, but (I won't)" comes across as extremely elitist, and to some people, quite repugnant. If that's not how you mean to come across, simply omit that first bit before the comma, and you will come across much more amicably.

[Cushman]

That's a great tip, thanks. I really meant that I'd love to explain it, but you're right that it doesn't come across that way :)