JohnH said:
I find this quite confusing. So you're saying that QED, the most successful theory in physics--how do you say it--almost coincidentally gets the correct answer?
It's not a coincidence. Feynman invented his diagrams to represent the series of integrals that emerge from a perturbative calculation of scattering processes in QFT/QED.
JohnH said:
You're saying that this convoluted mathematical process predicts the right outcome and yet has absolutely nothing to do with the actual process itself?
The process, such as it is, is described by the interaction hamiltonian, which leads mathematically to the series of integrals and the Feynman diagrams.
JohnH said:
If we're talking about how multiple probabilistic fields might evolve over time, it seems to me that such an approach might be described as "realistic." Would I be, in my ignorance, the only one who sees it that way?
The heart of the matter is whether QFT is a
complete theory of nature, in the sense that it tells us about everything that is measurable and, by implication, everything this is knowable.
Some physicists would like a more "realistic" theory of nature. You can look up Bohmian Mechanics, for example.
JohnH said:
Is there some logical wall that has prevented the entirety of all serious physicists from going down that road?
Most physicists accept that QFT is the best theory we have and accept what nature appears to be telling us. That the elementary interactions are probabilistic and cannot be described in classical, realistic terms. The alternative is to look for "realist" theories that meet preconceived human notions of how nature
ought to be.
From my perspective, the more you study QM/QFT the more sense it makes and the more inevitable it seems that nature at the fundamental level cannot be like the classical, macroscopic world.
The problem with the alternative is that you are most likely wasting your entire working life, motivated by little more than a natural human prejudice.