Are Electrons Really Indistinguishable in the One Electron Universe?

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Discussion Overview

The discussion centers around the philosophical implications of the 'one electron universe' concept proposed by Feynman and Wheeler, particularly focusing on the identity and existence of electrons. Participants explore the nature of electrons as indistinguishable particles and the criteria for existence in a physical context, touching on both theoretical and philosophical aspects.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested
  • Meta-discussion

Main Points Raised

  • Some participants reference the 'one electron universe' as a thought experiment, questioning whether electrons can be said to exist given their indistinguishable nature.
  • Others argue that electrons do have an identity based on their association with specific atoms, suggesting that this distinction is sufficient for their existence.
  • One participant emphasizes that while electrons are indistinguishable in terms of properties, they cannot occupy the same state, which implies a form of distinction among them.
  • Another participant challenges the philosophical framing of existence, stating that the concept of existence does not affect the physics of atomic models.
  • There is a mention of Feynman's own conclusion that the 'one electron universe' is impossible, as it raises questions about the number of electrons compared to positrons.

Areas of Agreement / Disagreement

Participants express differing views on the implications of indistinguishability for the existence of electrons. While some assert that electrons can be considered distinct entities, others maintain that their indistinguishable nature raises legitimate philosophical questions about their existence. The discussion remains unresolved with multiple competing views.

Contextual Notes

Participants highlight the complexity of defining existence in a physical context, particularly in relation to indistinguishable particles. The discussion also touches on the limitations of philosophical arguments in the face of established physical theories.

Quotidian
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I have heard that Feynman and Wheeler briefly discussed the idea of the 'one electron universe'. According to Wikipedia it came up as follows:

Feynman said:
I received a telephone call one day at the graduate college at Princeton from Professor Wheeler, in which he said, "Feynman, I know why all electrons have the same charge and the same mass" "Why?" "Because, they are all the same electron!"

It wasn't really a serious idea, more a 'thought experiment'. But what interests me is the fact that electrons are literally indistinguishable. Not only do they all have exactly the same properties, but 'it's essentially impossible to tell them apart at all. This is because determining specific electrons by their position would require measuring their trajectories with exact precision, and the laws of quantum mechanics forbid this.' 1

So this leads me to ask the question: do electrons exist? The obvious answer is, of course they do, you can capture their signal in all kinds of experiments. But the criterion for something that 'exists' is generally that it has an identity - it is 'this' as distinct from 'that'. The word 'exist' means to stand (ist) apart (ex).

So the 'one-electron universe' is not really that whimsical an idea. Something corresponding to 'electrons' can certainly be described, and it fulfils certain functions and turns up in predictable ways. But whether it exists can still be legitimately questioned. (I know that this is a tricky philosophical issue, but I would be interested to hear others' views on it.)
 
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Electrons do have an identity that separates them, the electron in one atom can be associated with that atom versus one in another.
 
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Quotidian said:
But the criterion for something that 'exists' is generally that it has an identity - it is 'this' as distinct from 'that'. The word 'exist' means to stand (ist) apart (ex).
Macroscopically, negative charges repel other negative charges, and we have deduced this is a mass version of the same property in individual negative charges. You can't physically put two electrons in the same space and appear to have one electron the way you can with, say, two congruent triangles. So, it is electrons, themselves, that tell us they are distinct entities from each other.

But, the thing electrons are mostly distinct from are protons and neutrons. To propose that electrons might not exist because we can't distinguish one electron from another (in the sense they all have the same properties), is just kind of whacky, and would require we also propose protons and neutrons don't exist for the same reason. Then you'd have to propose nothing exists.
 
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Quotidian said:
I have heard that Feynman and Wheeler briefly discussed the idea of the 'one electron universe'. According to Wikipedia it came up as follows:
It wasn't really a serious idea, more a 'thought experiment'. But what interests me is the fact that electrons are literally indistinguishable. Not only do they all have exactly the same properties, but 'it's essentially impossible to tell them apart at all. This is because determining specific electrons by their position would require measuring their trajectories with exact precision, and the laws of quantum mechanics forbid this.' 1

So this leads me to ask the question: do electrons exist? The obvious answer is, of course they do, you can capture their signal in all kinds of experiments. But the criterion for something that 'exists' is generally that it has an identity - it is 'this' as distinct from 'that'. The word 'exist' means to stand (ist) apart (ex).

So the 'one-electron universe' is not really that whimsical an idea. Something corresponding to 'electrons' can certainly be described, and it fulfils certain functions and turns up in predictable ways. But whether it exists can still be legitimately questioned. (I know that this is a tricky philosophical issue, but I would be interested to hear others' views on it.)

Electrons are not special by being indistinguishable. See, for example:

https://en.wikipedia.org/wiki/Identical_particles

You have not really grasped what it means for electrons to be indistinguishable. Although you cannot label individual electrons (or other elementary particles) in any way, it's also the case that no two electrons can be in the same state. In an atom, for example, there can only be one electron in each possible state. If there are two in the same "energy" state, then one will be spin-up and one spin-down.

Finally, the meaning of the word "exist" has no relevance to the physics of an atom, for example. You could conclude that electrons do not exist and the standard model of the atom with its electrons would be no better or worse as a result.
 
Electrons do have a position in space and time (sort of) so they are not indistinguishable from each other, what Feynman was talking about was the fact that they seem to have no internal structures so that if you pulled one out of a box with some electrons in it, examined it, then put it back and pulled another one out, you wouldn't be able to determine if it was the same one or not.

The one electron universe was quickly determined to be impossible by Feynman himself, who according to him, he immediately asked then why there were more electrons than positrons.
 
Since we don't do philosophy anymore, thread closed.
 

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