Electron tunneling and classic electrdynamics.

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    Electron Tunneling
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Discussion Overview

The discussion revolves around the concept of electron tunneling, particularly in the context of classical electrodynamics as described by the Maxwell-Lorentz equations. Participants explore whether tunneling could have been proven impossible or predictably quantified within this classical framework, as well as drawing analogies to other wave phenomena.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions whether electron tunneling could have been proven impossible within classical electrodynamics.
  • Another participant suggests that tunneling phenomena occur in various wave problems, indicating that it involves regions of no wave propagation but decay-like solutions.
  • Frustrated total internal reflection is introduced as an analogy for tunneling, with a participant noting its occurrence between closely placed glass plates.
  • There is a discussion about the conservation of energy related to the evanescent wave in frustrated total internal reflection, with two interpretations proposed regarding photon energy transfer.
  • Participants express curiosity about the empirical detectability of evanescent waves and whether they are merely theoretical constructs.
  • Questions arise about the nature of photon interactions during the "overhearing" phenomenon, including whether it implies actual crossover of photons.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the implications of tunneling in classical electrodynamics, and multiple competing views remain regarding the interpretations of energy conservation and the nature of evanescent waves.

Contextual Notes

Limitations include the dependence on definitions of tunneling and evanescent waves, as well as unresolved questions about the empirical detection of these phenomena.

Austin0
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Hi
Supposing that someone had come up with the hypothese of electron tunneling before the discoveries and mathematical structure of QM... Solely within the Maxwell-Lorentz mathematical structure :
1) Could it have been proven that tunneling was impossible ??

2) Could it have been predictably quantified? Probabilities of occurrence calculated for ranges of energy levels , ranges of potential barrier penetration for energy levels etc.

My knowledge of electrodynamics is totally insufficient to have any real idea so I am hoping that someone who knows both classic and QM might have some kind of answer available.
Thanks
 
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Austin0 said:
Hi
Supposing that someone had come up with the hypothese of electron tunneling before the discoveries and mathematical structure of QM... Solely within the Maxwell-Lorentz mathematical structure :
1) Could it have been proven that tunneling was impossible ??

2) Could it have been predictably quantified? Probabilities of occurrence calculated for ranges of energy levels , ranges of potential barrier penetration for energy levels etc.

My knowledge of electrodynamics is totally insufficient to have any real idea so I am hoping that someone who knows both classic and QM might have some kind of answer available.
Thanks

Tunneling phenomena occurs in all kind of wave problems. Its a region where there is no wave propagation but a decay like solution. For example you could have overhearing between two optical fibers when distance between is around the wavelength of the light. You could see it as the "particle" photon tunnels (classically forbidden) in analogy with an electron that tunnels.

Also light and acoustic waves could be confined and quantized, its called resonance modes, where the frequency is quantized. Take that frequency and multiply with Planck's constant and you get an energy!
 
per.sundqvist said:
Tunneling phenomena occurs in all kind of wave problems. Its a region where there is no wave propagation but a decay like solution. For example you could have overhearing between two optical fibers when distance between is around the wavelength of the light.

This is known as frustrated total internal reflection and can be observed by placing two very flat glass plates very close together without actually touching.
 
jtbell said:
This is known as frustrated total internal reflection and can be observed by placing two very flat glass plates very close together without actually touching.
Hi Although this is far from my original question it is a fascinating topic and new to me.

I am unclear on the conservation of energy regarding the evanescent wave that passes the diffraction barrier. Does this simply mean that
1) a photon that would have been reflected is now in the second medium with a loss of one photons energy from the reflected total in the first plate
or does it mean that
2) the evanescent energy that would have simply dissipated is now an active photon??

I would normally assume number 1) but with QM I am not so sure.
Also I am curious whether the evanescent wave that is presumed present even if a second plate is not, is something that is empirically detectable or is it just a theoretical assumption?
Thanks
 
per.sundqvist said:
Tunneling phenomena occurs in all kind of wave problems. Its a region where there is no wave propagation but a decay like solution. For example you could have overhearing between two optical fibers when distance between is around the wavelength of the light. You could see it as the "particle" photon tunnels (classically forbidden) in analogy with an electron that tunnels.

Also light and acoustic waves could be confined and quantized, its called resonance modes, where the frequency is quantized. Take that frequency and multiply with Planck's constant and you get an energy!

Hi
When you say overhearing does that mean actual crossover of photons??
It would seem that statistically the exchange would be reciprocal so how do they detect the phenomenon?
When you said classically forbidden does that imply yes to 1) of my original question and no to 2) ?
Thanks for your responce you have given me some new and interesting subjects to explore.
 

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