B Understanding Waves, Particles and Probabilities

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Wave-particle duality is explained through quantum mechanics by modeling particles, like electrons, with a wavefunction that represents a probability distribution in space. This distribution resembles a wave, accounting for the wave aspect of duality, while the particle aspect emerges during interactions. Classical physics previously categorized light as a wave and electrons as particles, but experiments revealed their dual behavior. Quantum mechanics does not inherently include wave-particle duality as a fundamental concept; rather, it provides a unified framework that describes both behaviors. Understanding this model clarifies the relationship between probability waves and particle interactions in quantum theory.
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Am I getting close to a basic understanding of probability waves?
In the ongoing quantum interpretations and foundations thread vanahees71 explained to me that the wave particle duality has been explained by the model where the position of a particle is calculated according to a probability distribution traveling in space.

Am I understanding this correctly.The probability distribution has the same shape as a wave and that accounts for the wave part of the wave-particle duality?

And the particle part is when an interaction actually takes place?

Or am I nowhere near understanding this still?
 
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geordief said:
Am I understanding this correctly.The probability distribution has the same shape as a wave and that accounts for the wave part of the wave-particle duality?
Roughly, yes.
geordief said:
And the particle part is when an interaction actually takes place?
The wave looks like a particle when the width of wave is small. Interaction can be a part of the reason why this happens, but it's not that simple.
 
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geordief said:
Summary: Am I getting close to a basic understanding of probability waves?

In the ongoing quantum interpretations and foundations thread vanahees71 explained to me that the wave particle duality has been explained by the model where the position of a particle is calculated according to a probability distribution traveling in space.

Am I understanding this correctly.The probability distribution has the same shape as a wave and that accounts for the wave part of the wave-particle duality?

And the particle part is when an interaction actually takes place?

Or am I nowhere near understanding this still?
Classical physics involves two seemingly different physical things: particles and waves. It was assumed that some things were particles (e.g. electrons) and some things were waves (e.g light).

Then certain experiments were carried out that appeared to show light behaving like a particle (photoelectric effect) and electrons behaving like waves (electron diffraction). This was called wave-particle duality.

QM explains wave-particle duality by modelling an electron using a wavefunction. This single model explained both its particle-like and wave-like behaviour.

QM itself doesn't have wave-particle duality as part of the theory. And, indeed, some popular QM textbooks (e.g. Griffiths and Sakurai) either mention it only as a historical footnote or not at all.
 
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We often see discussions about what QM and QFT mean, but hardly anything on just how fundamental they are to much of physics. To rectify that, see the following; https://www.cambridge.org/engage/api-gateway/coe/assets/orp/resource/item/66a6a6005101a2ffa86cdd48/original/a-derivation-of-maxwell-s-equations-from-first-principles.pdf 'Somewhat magically, if one then applies local gauge invariance to the Dirac Lagrangian, a field appears, and from this field it is possible to derive Maxwell’s...