What Term must be used for this formalism?

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Discussion Overview

The discussion revolves around the interpretations of quantum mechanics, particularly focusing on the nature of wave functions and the concept of localization of particles like electrons. Participants explore the implications of the Many Worlds, Bohmian, and Copenhagen interpretations in relation to the reality of wave functions and the behavior of particles before and after measurement.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants propose that the wave function should be considered a real entity, raising questions about what term should be used to describe this interpretation.
  • Others suggest that the concept of localization in quantum mechanics is problematic, as the three main interpretations do not adequately model how particles localize upon measurement.
  • A participant questions the nature of electrons before measurement, suggesting they are not localized and exist as state vectors, similar to the Many Worlds interpretation where they are not considered as definitive particles.
  • Another participant emphasizes that the wave function describes the probability distribution of an electron's location, rather than the electron being the wave function itself.
  • There is a mention of the idea that quantum mechanics does not provide clarity on the state of particles when not observed, leading to further inquiry about whether particles exist in all possible states simultaneously before measurement.

Areas of Agreement / Disagreement

Participants express differing views on the interpretation of wave functions and localization, with no consensus reached on the terminology or the implications of these interpretations.

Contextual Notes

The discussion highlights limitations in the interpretations of quantum mechanics, particularly regarding the definitions of localization and the nature of wave functions, which remain unresolved.

jlcd
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I noticed something especially in Physicsforums. It seems we have cornered quantum stuff to attain classical attributes.What I mean is this. You have the 3 main interpretations

Many Worlds
Bohmian
Copenhagen

In all 3 versions. there are either classical worlds branching or particle with trajectories or subjective Bayesian views. What happens to the idea about wave function of an electron being also present elsewhere.. or in the absence of measurement to determine a particle properties.. the particles has no definite particles? What I'm asking is.. what interpretation should it be called.. this idea wave function being real? There should be a name of it especially when you can't falsify it so it should be a valid interpretation too.
 
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I'd call it esoterics ;-)).
 
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Or let me ask about this question of localization. Quantum system like the electrons in atoms are delocalized.. upon measurement, it localizes. But the 3 main interpretations can't model this localization. In Many Worlds.. the electrons before measurement has a world of each own? or are they delocalized? In Bohmian.. it has trajectories as all time meaning before measurements.. the electrons in atoms have trajectories.. in Copenhagen.. the wave function is just tools or subjective (but then in Copenhagen what happens to the electrons in the atoms?)
 
What do you mean by localization? You measure the position of, say an electron. That means the electron has interacted with some device like a photoplate leaving a track which let's you read off the position at an accuracy given by the apparatus's resolution. If you know the quantum-theoretical state, you can know only the probability for where the electron will be found, and nothing else. What happens to the electron after the measurement depends on the apparatus. In the case of a photoplate it gets absorbed.

For your electron in an atomic state you can use some scattering experiment, e.g., shooting with another electron or photons on the atom and measure the electromagnetic form factor of the atom, from which you can get an idea of the charge-density distribution of the electrons within the atom. Usually then you excite the atom or even kick out one or more electrons. You can calculate the various transition properties from the initial (usually the ground state) to another atomic state (including scattering states, where you are left with an ionized atom and one or more free electrons) from quantum scattering theory.
 
vanhees71 said:
What do you mean by localization? You measure the position of, say an electron. That means the electron has interacted with some device like a photoplate leaving a track which let's you read off the position at an accuracy given by the apparatus's resolution. If you know the quantum-theoretical state, you can know only the probability for where the electron will be found, and nothing else. What happens to the electron after the measurement depends on the apparatus. In the case of a photoplate it gets absorbed.

For your electron in an atomic state you can use some scattering experiment, e.g., shooting with another electron or photons on the atom and measure the electromagnetic form factor of the atom, from which you can get an idea of the charge-density distribution of the electrons within the atom. Usually then you excite the atom or even kick out one or more electrons. You can calculate the various transition properties from the initial (usually the ground state) to another atomic state (including scattering states, where you are left with an ionized atom and one or more free electrons) from quantum scattering theory.

What I meant was.. before measurement.. the electron are not localized.. they don't have physical locations. They are just state vectors. Is this also the idea of Many worlds.. where before measurement.. the electrons are not really electrons but just wave function?
 
Electrons "are" not the wave function, but the wave function describes the probability distribution of their location. A point particle in classical physics "is" also not a column of six position-momentum vectors.
 
vanhees71 said:
Electrons "are" not the wave function, but the wave function describes the probability distribution of their location. A point particle in classical physics "is" also not a column of six position-momentum vectors.

But without being observed.. there are only wave functions... Bill just wrote in the other thread that "QM is silent on what's going on when not observed." Perhaps you believe it is not silent? Pls. elaborate on whether photons/particles exist in all possible states simultaneously before measurement or others you have in mind.
 

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