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Edit: What can be explained by wave-particle duality that cannot be explained by waves?

My understanding of the Standard Model is that what we observe as a particle is really a quantized wave packet, and that all particle phenomenon can be described in that way. This answer states that quantum fields are both wave-like and particle-like.

For example, at low intensities, light is detected as single particles. Can that not be explained by the wave interacting with the detector in such a way that the wave collapses to a point, which is necessarily quantized? In what way is the Standard Model not describable purely as waves in quantum fields?

Someone cited particle tracks through a bubble chamber as a reason why wave-only is insufficient. Can this not be described as quantized wave packets?

Ethan Reesor
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    The question seems to be based on a presumed distinction between "particle" and "quantized wave packet." What is the distinction you have in mind? (The words that I put in quotation-marks are all overloaded in physics, so the intended meaning is not at all obvious from the words themselves.) – Chiral Anomaly Jun 18 '21 at 20:24
  • When I read posts on SE or Wikipedia, it seems that the consensus is that electrons etc cannot be described purely as wave phenomenon. I may be conflating terms, but I think of 'particles' as solitons - a strongly localized self-reinforcing wave. And I thought particle behavior could be described purely in terms of quantized solitons in quantum fields. And that seems like a really straight forward way to explain superposition and all that. But people keep on saying, "No, it's really this mysterious wave-particle duality and photons are really particles and waves." – Ethan Reesor Jun 18 '21 at 20:31
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    "No, it's really that this mysterious wave-particle duality means that photons have the properties of both particles and waves." is exactly right. It's meaningless to ask what is "really" going on as John Bell showed us thatt there is no (local) "reality." – mike stone Jun 18 '21 at 22:28
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    @mikestone In the context of Bell's theorem, 'realism' refers to the notion that there is some underlying hidden variable that explains the probabilistic behavior of quantum mechanics. It has nothing to do with ontology. In so much as the theorem is correct, in no way does it show that 'there is no (local) "reality"' in any ontological sense. It just asserts that local hidden variables theories are incorrect. – Ethan Reesor Jun 18 '21 at 22:47
  • I would say it’s insufficient because you can’t explain what a light wave is other than billions of photons particles. You should ask the same question about particles. – Bill Alsept Jun 19 '21 at 00:08
  • How can a red light photon be different from a blue light photon? – mmesser314 Jun 19 '21 at 00:13
  • @mmesser314 frequency is the difference between red and blue photon. – Bill Alsept Jun 19 '21 at 00:32
  • "explain what a light wave is other than billions of photons particles." I don't follow. What explanatory power does "billions of particles" have that "photon wave" or even "billions of wave packets" does not? – Ethan Reesor Jun 19 '21 at 00:37
  • @EthanReesor We’ve only description is insufficient because you cannot explain what a light wave is. A particle can be described. You don’t have to know everything about the particle for instance you don’t know what protons and neutrons exactly but they are particles. Photons are particles and are more sufficient than waves. – Bill Alsept Jun 19 '21 at 00:54
  • A particle can be physically described in many ways. A wave packet cannot be physically described in anyway. – Bill Alsept Jun 19 '21 at 01:28
  • @ Ethan Reesor. I have no idea what "ontology" means (the study of "things" perhaps?) but the surely usual account of Bell after Bernard d'Espagnat" is "no local reality"? Anywa,y I intended to be provaocative to start a debate about QM. Maybe I succeeded? :) – mike stone Jun 19 '21 at 01:29
  • @mikestone Ontology is the study of the nature of being. "The world is a simulation" and "Physics describes the true underlying nature of reality" are both ontological assertions in that they assert something about the nature of being. Beyond asserting that a local hidden variable theory cannot be consistent with observed phenomenon, Bell's theorem makes no assertions about the nature of being. That is, it makes no statements about what does or does not 'really exist' beyond ruling out local hidden variable theories. – Ethan Reesor Jun 19 '21 at 01:37
  • @mikestone John Bell had a limited view of what a particle could be or do. He never even considered oscillating or linear aspects of a photon. He only considered polarization. – Bill Alsept Jun 19 '21 at 01:38
  • @Bill Alsept: John Bell was a very experienced particle physicist. He co-discovered the Adler-Bell-Jackiw axial anomaly and its relation to the $\pi_0\to \gamma+\gamma$ decay. He knew full well how field theory worked and all properties of photons. – mike stone Jun 19 '21 at 01:42
  • @mikestone He still only considered polarization. – Bill Alsept Jun 19 '21 at 01:48

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"No, it's really that this mysterious wave-particle duality means that photons have the properties of both particles and waves." is exactly right. It's meaningless to ask what is "really" going on as John Bell showed us that there is no (local) "reality."

As Mermin says: there are only correlations (between measurements) but there are no correlates (things that are correlated).

A persistent belief that there is some "reality" is the biggest block to understanding quantum mechanics.

mike stone
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    I am asking specifically, in what way is a wave-only explanation insufficient? I have zero interest in metaphysics or what "reality" is. I am asking, why can't it be explained as waves? You do not answer my question. – Ethan Reesor Jun 18 '21 at 22:38
  • @Ethan Reesor: Because waves do not produce individual spots of light on a screen. – mike stone Jun 19 '21 at 01:30
  • I've only scratched the surface of quantum mechanics, but I fail to see why a soliton wave in the photon field cannot explain individual spots of light, or why that behavior could not be explained by QM interactions forcing the wave to localize to a soliton upon detection. – Ethan Reesor Jun 19 '21 at 01:40
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    @Ethan Reeson. The QM wave Schroedinger equation is linear. There can be no solitons in Schroedinger waves. The waves with solitons result from quantizing non-linear theories whose waves interact, and whose waves are not the waves of the Schroedinger equation. – mike stone Jun 19 '21 at 01:46
  • "The soliton model applied to the electrons can be extended to the electromagnetic field providing an unambiguous description for the photon." https://arxiv.org/abs/1612.00110 – Ethan Reesor Jun 19 '21 at 02:26