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Full Version: "Reality is just a quantum wave function"
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EXCERPTS: Philosophers of physics seek metaphysical models that are compatible with the reality of quantum entanglement, possible realities that can underlie these experimental appearances. Most models taken seriously today simply accept that there are brute correlations that can persist between objects in entangled states, even those that are separated by great distances. But another idea worth exploring is that the results of these Bell tests are trying to tell us that the three dimensions in which we experience the world are not the deepest reality. Rather, the nonlocality we observe over distances in three dimensions appears as a byproduct of a more fundamental spatial framework in higher dimensions. And in this higher-dimensional framework, the correlated subsystems of entangled particles are not separated at all.

The higher-dimensional approach along these lines that is most commonly discussed today is called wave function realism. This is the view that reality isn’t fundamentally a collection of objects – particles, atoms – spread out in three-dimensional space or even four-dimensional spacetime, but instead reality is fundamentally      a wave function, a field-like object that exists in some higher-dimensional quantum reality.

The idea of higher dimensions is familiar from string theory. [...] In quantum mechanics, the higher dimensions aren’t there as extra dimensions in addition to the usual three. Instead, in order to represent systems as entering into entangled states, quantum mechanics presents us with entirely distinct spatial frameworks. ... One such framework is configuration space. Configuration space representations were introduced in the nineteenth century to provide more rigorous and elegant formulations of classical mechanics. ... Another higher-dimensional framework for representing systems in quantum mechanics is Hilbert space...

[...] Though higher-dimensional representations like these are ubiquitous in quantum mechanics, usually physicists do not take them seriously as representing what our world is like.

[...] This distaste for higher dimensions arguably partly explains the rise of the Copenhagen interpretation of quantum mechanics.

[...] Not all physicists today are so resistant to taking higher-dimensional interpretations of quantum mechanics seriously. For example, the physicist Sean Carroll, in his recent book on quantum mechanics, Something Deeply Hidden, argues that the best interpretation of quantum mechanics takes it to represent the world fundamentally as a ray in Hilbert space. There are interesting arguments that  lead to a view like that, however, I myself am more sympathetic to wave function realism, a higher-dimensional interpretation of quantum mechanics that picks up where Schrödinger left off, and interprets the world fundamentally as a wave or field. In this case, the world is not a simple ray in Hilbert space, but instead a field, the wave function, spread out over configuration space.

[...] As I argue in my recent book, The World in the Wave Function, however, even if higher- dimensional frameworks like configuration space or Hilbert space might be indispensable to the formulation of quantum mechanics, that does not mean that those wanting to interpret these theories realistically must take them as describing a world with hidden dimensions. Since Bell, many different interpretational frameworks have appeared which provide alternative ways of making sense of the quantum formalism.

[...] The wave function realist argues that there is a deeper explanation for why we see these correlations. They are a manifestation of a field that is evolving in a higher-dimensional space in which there is no instantaneous action at a distance.

What is interesting is that the way alternative low-dimensional metaphysical frameworks have proven adequate to providing an interpretation of quantum mechanics is by giving up on fundamental locality. But in doing so, they have given up on trying to explain nonlocality. They just take it as brute, as given. In a sense, this is to give up on a very basic principle of science: that we explain correlations in terms of a common cause... (MORE - missing details)
If the "entangled particles are not separated at all" in higher dimensions, there's no reason to assume they are still a wave, or even a field, in higher dimensions. The wave characteristics would only exist as an artifact in our 4 dimensions. But then, this is from a philosophy professor.