For a simpleton like me, the problem with current models/understanding of how the universe fundamentally works is that the models are couched in mathematical equations.
The nature of math equations is to use assorted “units” and it is (in my simpleton world) the use of units that drives quantized models, where item X (a particle, say, is distinct from item Y (another particle). Compounding the drive to think of the world as being made up of particle/unit-based building blocks is that our everday world appears to have obviously discrete phenomena in which the players appear to be obviusly distinct from one another. A baseball–or photon–which changes its position relative to something else appears to be moving “through” whatever it is we call space.
If one considers math itself as a language, it is not hard to make a conclusion that mathematical equations may not be the route to the most beautiful understanding of how the universe actually works. It seems to me it is entirely possible that these equations–even when they are able to make remarkably accurate predictions about the world around us–are really just describing finer and finer behaviors–not smaller and smaller “particles.”
We think of a photon as a something moving through something else. We are aware that it’s not exactly a discrete “thing” because some aspects of what seems to happen don’t parallel discrete “things” (entanglement, for example). It is the language of math coupled with our observations in the macro world that constrains us to think of the photon as a discrete “thing” moving “through space.”
Even if math predicts correctly what will happen, and even if we get better at marrying quantum and GR math, we do not necessarily arrive at what is really happening.
Consider, for example, that “space” and “stuff” might be exactly the same thing. What we are and what we observe is not discrete things interacting; it’s behaviors of the same thing. A photon does not “move” through space; a photon is space behaving differently. Gravity is not some external “force” but is a perfectly smooth quality of whatever it is we want to call the one thing that makes up our universe.
I suppose an analogy might be that “space” (the one, perfectly smooth “thing,”) has a quality similar to density, and what we call particles (more precisely, perhaps, the observations that we quantize as particles) are denser space.
It may be that there is no such thing as finding the atom of which all things are made, and exist in space. It may be that the universe is smooth all the way down–so to speak–and that what we think of as finer and finer building blocks are really just finer and finer descriptions of behaviors.
If one discards both natural language and mathematical language as ways to describe what really is, then communicating anything does not become meaningful, so my musings here are not meant to be particularly worthwhile.
But deep inside this dullard’s fog is a gut feeling that we will eventually figure out that space and “particles” are the same thing…perhaps in the way we (well, Einstein et al) figured out that matter and energy are the same thing. The particle model will remain as a very useful way to package up observed behaviors, but we’ll stop thinking of particles as existing in space and shift to the notion that they are exactly the same thing, without any boundary at all, all the way down.
In such a construct it is not difficult to think of gravity as nothing more than thinner space…and dark energy as thicker space (?)…