Quantum field theory and wave particle duality

[LifelongLearner125]

TL;DR Summary

Quantum field theory (QFT) states that every thing is a field, particles are fields and forces are fields. The early quantum theory talks a lot about electrons behaving like a particle and a wave. Is it the same phenomenon as explained by QFT that particles have a corresponding field associated with them which can 'wave'?

I recently watched this lecture "Quantum Fields: The Real Building Blocks of the Universe" by David Tong where the professor provides a succinct explanation of QFT in about 6 minutes around the midway mark.


The main point being that there are fields for particles and fields for forces and the particles get their properties by the interaction of the particle fields with the force fields. Like Charge of an electron is the outcome of the electron field interacting with the field associated with electromagnetic force.
is this notion of particles having a field same or corresponds to the wave particle duality of early quantum physics that is often described using the double slit experiment?

 

[PeterDonis]

there are fields for particles and fields for forces

And yet the "fields for forces" have particles too--the photon is the particle of the electromagnetic force field.

I see what he's basically trying to get at--he's referring to the distinction between boson and fermion fields, where the former are "forces" and the latter are what he calls "particles"--but I don't think it's anywhere near as simple as he seems to be trying to make it.

is this notion of particles having a field same or corresponds to the wave particle duality of early quantum physics that is often described using the double slit experiment?

Not really. The early QM "wave particle duality" was just a way of describing how surprised physicists were at that time that everything could be made to behave like either a particle or a wave, depending on what experiment you did. Physicists before that had thought that things like light were waves and things like electrons were particles. Then they did experiments that showed light behaving like particles and other experiments that showed electrons behaving like waves, and everyone started saying "wave particle duality" as if that somehow explained what was going on instead of just describing their confusion.

In quantum field theory, "wave" and "particle" are just shorthand ways of describing certain kinds of quantum field states. The same experimental results that confused everybody before are still there, but now they have an actual explanation: that the underlying entities are neither waves nor particles, but quantum fields, and yes, you can do certain experiments that make quantum fields behave like particles, and other experiments that make them behave like waves. And you can also find quantum field states that can't be easily described as either particles or waves.

 

[vanhees71]

I think that "wave-particle duality" strictly and exclusively belongs to the "old quantum theory". None of the physicists developing this "theory" has been satisfied with it to begin with. Particularly Einstein was very critical about his own work about "light quanta".

The resolution of all the quibbles of "old quantum theory" is "modern quantum theory", developed in three versions in 1925/26: (a) matrix mechanics, heuristically stated by Heisenberg, then worked out by Born and Jordan (including quantization of the electromagnetic field by the way, (b) wave mechanics by Schrödinger (including the proof that it's equivalent to matrix mechanics), (c) transformation theory by Dirac (the representation free formulation with operators and bras and kets, including also quantization of the electromagnetic field).

According to modern quantum theory there is no self-contradictory wave-particle dualism anymore. That relativsitic QT is today formulated exclusively as QFT is due to the fact that when having scattering processes at "relativistic energies" there are no conserved particle numbers of any kind. Only the various charges of the Standard model (electric charge, baryon number, etc.) are conserved but you create and annihilate all kinds of particles in such processes. That's why a QFT formulation is most convenient, because QFTs particularly describe such situations where particles can be annihilated and created.