The Soul Wanderers

Can something be in two places at once? Well, it matters what kind of "thing" you're talking about. If you're an electron, or another subatomic particle, then sure, why not? But larger things, such as you, can't hope to do such a thing.
Small particles seem to be able to exist in many places at once, that is, until you observe them. If you try to measure their position, you will come up with a definite value, but before you make an observation, they exist in a superposition of all possible states. This is called the Copenhagen Interpretation. In the picture below, the graph on the left shows the probability of observing a particle in a particular location (in x and y coordinates), and you can see that there is a large spread-out region where the particle is most likely to be found. This is represented by the particle's wavefunction (ψ). The particle isn't "in" any one spot, but all over that area, though it is more likely to be found at the peak.
However, when an observation or measurement is made, the wavefunction "collapses" so that the particle no longer exists in a general spread out region, but a particular spot (the spike on the graph to the right).
So what does this have to do with writing?
Well, the writer, when creating a world and its characters, has to in a sense be in many places at once. You can't just create one character alone in a vat, but you need to consider how they interact with their world, what they're doing, what other characters they know...You need to know everything at the same time, to have a vision to weave dozens of characters into a plot and develop them externally and internally. Things don't happen in a sequence: like the particles of quantum mechanics, you have to capture dozens, even hundreds, of things at one, and somehow construe them into a unified story. The ideas for a story starts out as a nebulous thing, like a particle spread out over a larger area, but from that, when we bring or attention to them as an observer or author, we "collapse" these ideas into a story.
You could have written the story in a different way, just as a particle could have been somewhere else when you went to look at it. But the key is that when you decide on a story, you make a choice. What characters do you include? Whose point of view is it? What path do they take to further the plot? All these questions are intrinsically related, so we have to capture many things at the same time.
Often, it is hard to do this, and there is a fine line between scatter-brained multitasking and capturing many things at once. So sometimes, we have to focus on one thing at a time, like an event or a character's backstory. But I think that the real "juice" of writing comes when we capture many things at once, to unite them to a whole and look down on our story from above. Then things should flow naturally, or at least, that's the idea. It isn't always easy to put ideas into practice, and I find that when I write, moving between the macro to micro picture of what is going on in the story is difficult. Sure, maybe I know what megalomaniac plan the villains have, but to move down to visualize what they're actually doing in the present moment sometimes isn't easy.
This is when you have to "be a particle", to exist in a kind of superposition of many different ideas, and in doing so, be able to unite them into a story that makes a compelling tale on both the small scale and the large scale. You're like the picture on the left, spread out over a region of many possibilities that are the different elements of your story. The next step, to make them into a unified tale, is the "measurement". That spike on the right graph is your story, seemingly a linear tale, but arising from a state of many different elements.

I have to add that there is another interpretation other than the Copenhagen one that I find more compelling (though in physics, most people accept the Copenhagen approach). This is the Many Worlds Interpretation, pictured below. In this interpretation, a particle exists in every possible location, but each of these locations exists in a parallel universe. We only observe one thing happening because we are not in contact with these parallel universes. So in this scenario, the observer has no magical ability to make wavefunctions collapse, but rather, when they make a measurement, they only measure the particle's position that exists in their universe.

In this case, when it comes to writing, we can say that we have to access many parallel worlds to write, each with different plot threads, with different characters, and from them, we must create a unified narrative that will be perceived as the single measured position in our world (the arrow in the diagram), even though it was born from many elements across many universes.

So, whether there is one world or many, writers have to learn the art of being in more than one place at the same time. Sounds like magic, but our thoughts are quantums of energy, and so they too exist in the strange world ruled by quantum mechanics.

Any ideas? Is this doable, or crazy? Comments welcome!