Hi Canute
Someone once observed that scientists are almost always right when they say something is possible, and almost always wrong when they say something is impossible. I would not say that a resolution to this issue is impossible for physics, but I would say that some physicists are currently working very hard to solve a paradox. The paradox is sharp in the three dimensional space plus one dimension of time view, but is easily resolved in higher dimensions, as I tried to argue above.
I think our physicists and mathematicians could learn something about the paradox if they would ask philosophers and mystics, who have been working on this same problem for centuries. Why do we have to battle over this same ground again and again, with increasingly elaborate models and more time consuming and expensive calculations, when it is clear as day to anyone who has thought about it that there is and can be no motion in spacetime? I speak of motion in the usual sense of some difference in a spatial quantity compared to some difference in a time, as in miles per hour or Kilometers per second and so on.
If there is no motion then there can be no perturbation, can there? The old Zen koan about two monks watching the movement of a flag in the wind. One says the flag moves, one says the wind moves. The master, overhearing them, says it is their minds that are moving. The master knows that they are arguing over an illusion. The wind, the flag, nada. The only motion occurs within the mind. The spacetime reality is as fixed as the magnetic bits on a CD. They only make the illusion of music or video when the disc is spun under a lasar light. The point of light, traveling across the surface of the disc, creates the illusion of movement, just as the mind of the monk, passing through spacetime, creates the illusion of a flag moving in the wind.
The question of locality is very similar. How do we determine if a thing is close or far? We do not want spooky action at a distance, but how do we determine that there is or is not a distance? We get our common notion of space from swatting at danglies in the cradle. We see objects hidden by other objects, then we see them reappear as the intervening object moves aside. So we deduce that there is space, since the two objects can pass without bumping into each other. But math and physics introduces us to all kinds of spaces, vector space, phase space, configuration space, cyberspace. Some of these spaces obey different rules from the space we have from the cradle. Advocates of wormholes want us to believe that places which are not local in three dimensional space can be local in four dimensional space...see, you just fold the paper, and there it is. Never mind that three dimensional space cannot be folded like a two dimensional paper surface. And you and I, talking like this in cyberspace. Are we right next to each other or far apart in some dark uncrossable void? Questions about locality become meaningless.
Since the physicists and mathematicians are reluctant to study mysticism, I, having studied mysticism, have decided to undertake the study physics and math. I can tell you this: The language of physics and math is a lot more obscure and self-referential than is the language of mysticism. Background independent. Perturbative. DeSitter space. Calabi-Yau manifold. And indicies! It goes on and on. Vectors and tensors and spinnors, oh my. Dorothy only had to deal with lions, in the end, and tigers and bears never even entered the story. Lucky girl. Here, we have the whole menagerie, and most of the players are anything but cowardly.
oh well. I am trying, anyway.
Richard