Comments by "Lepi Doptera" (@lepidoptera9337) on "Quantum Mechanics of the Electron" video.

  1. There are no particles. Quanta are small amounts of energy. When we detect one we get a "click" in a detector. The "clicks", i.e. when and where these detectors absorb a small amount of energy seem random. We therefor start to collect statistical information (histograms) about them. In the limit of large numbers these histograms become probability distributions. The theory predicts these probability distributions as the product between a wave function, its conjugate complex and a Hermitian projection operator that represents the absorption spectrum of a physical measurement system (the detector). What happens is that almost nobody who makes these videos actually knows WHY the formalism looks the way it looks. For that you would have to read Heisenberg's matrix mechanics papers, where this is somewhat laid out in a language that still relates to physics and that will give you a bit of physics intuition about what is happening. A few years later a mathematician called von Neuman generalized the relatively straight forward physics and math in Heisenberg's papers to an abstract mathematical formalism that comes from functional analysis (the mathematics of linear operators and function spaces). At that point the connection to measured quanta of energy disappears from the textbooks and is replaced with a general notion of "quantum mechanical state". You also lose a sense that this "state" means the state of a quantum mechanical ensemble, i.e. an infinite repetition of the same experiment. Instead it starts looking like as if the wave function relates to an individual system. That is complete nonsense. It was never constructed that way, neither by Heisenberg nor by von Neumann. It's just easy to loose sight of the translation between physical measurements ("clicks") and mathematical formulas.
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  2. No, they aren't different. Quantum mechanical effects are NOT restricted to "small thing" and the usual notions of physics (energy, momentum, angular momentum and charge) work exactly the same.
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