Light Interaction with Electrons in Glass

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    Glass Photons
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Discussion Overview

The discussion revolves around the interaction of photons with electrons in glass, specifically whether a photon retains its identity after being absorbed and re-emitted by an electron. Participants explore concepts of entanglement, the nature of photons in different media, and interpretations of quantum mechanics related to these interactions.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants propose that upon absorption by an electron, a photon is not the same as the one that is re-emitted, suggesting that while the re-emitted photon may be identical in properties, it is fundamentally a different photon.
  • Others argue that the photon retains its identity through the interaction, asserting that it is merely perturbed rather than replaced during its transit through materials like glass.
  • A question is raised about the entanglement of photons, specifically whether a photon that has interacted with glass maintains its entanglement with another photon after the interaction.
  • Some participants challenge the absorption-reemission model, suggesting that it does not adequately explain the behavior of photons in experiments, such as the Afshar experiment, which they believe does not require this model for its interpretation.
  • There is a discussion about the coherence of photons and how interactions with materials affect their properties, with some suggesting that coherence does not imply identity.

Areas of Agreement / Disagreement

Participants express differing views on whether a photon retains its identity after interacting with electrons in glass, with no consensus reached. The discussion includes multiple competing interpretations of quantum mechanics and the nature of photon interactions.

Contextual Notes

Participants reference various quantum mechanics concepts and experiments, including the Afshar experiment and the principle of complementarity, without resolving the implications of these references on the discussion at hand. There are also mentions of assumptions regarding the behavior of photons in different media and the nature of wave coherence.

thenewmans
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If I look through glass, the photons I see have encountered electrons. Is the photon that went into an electron the same one that comes out?
 
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You can never truly state that any particle retains its individual identity, for that is a question demoted of any fundamental basis. Upon the absorption of a photon by an electron, a subsequent collision releases an identical photon traveling in a slightly altered path. Though however identical these photons may be to one another, that does not conclude that they are in fact the same photon.
 
So let’s say photons A and B are entangled and B goes through glass or bounces off a mirror and photon C pops out. (B and C might be the same.) Is C just as entangled to A as B was?
 
There is a problem anyway : photon only exist in vacuum. You can insist to describe the propagation of light with photons in the vacuum in the glass, but that is not the proper way to describe it : in the glass, you have another effective wave propagating.

There is no way to bounce photons. You can only absorb them and re-emit another one.
 
thenewmans said:
So let’s say photons A and B are entangled and B goes through glass or bounces off a mirror and photon C pops out. (B and C might be the same.) Is C just as entangled to A as B was?
Entanglement experiments often route photons through wave filters, off mirrors, and beam splitters, etc. before sending them to polarization detection. And since correlations are maintained you have to say YES.

However I do not accept the absorption-reemission explanation. IMO it is the same photon; perturbed by, but not replaced when transiting those things it went through.
 
RandallB said:
However I do not accept the absorption-reemission explanation. IMO it is the same photon; perturbed by, but not replaced when transiting those things it went through.
You may like it your may not, but wave coherence does not mean it's the same photon.

Otherwise, you have Afshar which-way experiment to explain.
 
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humanino said:
You may like it your may not, but wave coherence does not mean it's the same photon.

Otherwise, you have Afshar which-way experiment to explain.
I do not see in Afshart any requirement for absorption-reemission of photons by atoms and or the electrons in them. So I don’t see your Point.

I case it is involved some how; I do not accept the idea that the http://en.wikipedia.org/wiki/Principle_of_complementarity" , even though Afsher himself did not like it. And I will “in due course”, but in my priority and time, submit that to FOP as he requested.
 
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RandallB said:
I do not see in Afshart any requirement for absorption-reemission of photons by atoms and or the electrons in them. So I don’t see your Point.

I case it is involved some how; I do not accept the idea that the http://en.wikipedia.org/wiki/Principle_of_complementarity" , even though Afsher himself did not like it. And I will “in due course”, but in my priority and time, submit that to FOP as he requested.
Interesting. The way I see it, the photon is in a coherent sum of position eigenstates after the pinholes. Assuming the wires infinitely thin, and interferences there, then you have the lens, which is a momentum measuring device. It breaks the position coherence. Now you cannot assume this if you say this is the same photon before and after the lens. But I do not see any QED diagram of photon-non-interaction, so I don't understand how a single photon could be deflected by a lens if there was no atomic interaction (for the uses of lenses in most EPR experiments).

Note that this simple explanation is not contradictory to most of the other ones. I don't know of any experiment challenging elementary QM which cannot be simply explained once it is understood. Note also that the lens does not measure angular momentum.
 
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