What Happens to an Electron During Quantum Tunneling?

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Discussion Overview

The discussion revolves around the behavior of an electron during quantum tunneling, particularly when it encounters a potential barrier that it does not have enough kinetic energy to overcome. Participants explore various interpretations and implications of this phenomenon, including the nature of kinetic energy within the barrier and the potential for observing the electron in different forms.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Syed questions what happens to an electron within a potential barrier during tunneling and whether it can be observed with negative kinetic energy.
  • Some participants suggest that the electron exists simultaneously within and outside the barrier.
  • One participant explains Bohm's theory, noting that while kinetic energy is positive, there exists a negative quantum potential energy, and contrasts this with the Copenhagen interpretation which denies the existence of negative kinetic energy.
  • Another participant proposes that the electron could be observed as a positron during tunneling, inviting further discussion on this perspective.
  • A later reply dismisses the previous point about observing the electron as a positron, suggesting that misinterpretations of basic physics should not be discussed without proper education.

Areas of Agreement / Disagreement

Participants express differing views on the interpretation of quantum tunneling, with no consensus on the nature of the electron's behavior within the barrier or the implications of negative kinetic energy. The discussion remains unresolved regarding the validity of observing the electron as a positron.

Contextual Notes

Some claims rely on specific interpretations of quantum mechanics, such as Bohm's theory and the Copenhagen interpretation, which may not be universally accepted. The discussion includes assumptions about the nature of kinetic and potential energy that are not fully explored.

KAZSyed
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Hi I'm Syed ,loving Physics from my childhood.I have no knowledge of hard core Physics,though I'm an M.Sc Physics.My area of interest is Theoretical Phyiscs,which needs Paper,Pen and Brain of which I have the first two and lacks third.So,Please help me to do better in this field.I'd be much obliged for that.

Here is the question I persevere to know a Better Answer .

What happens to an electron within a Potential barrier when it tunnels through it without enough KE to overcome it ?

Can we observe an electron with negative KE within the barrier ? What is the Physical Meaning of this all ?
(I am not satisfied with the answer David Bohm has given in his book)
 
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What answer does Bohm give? I haven't read his book.
 
"What happens to an electron within a Potential barrier when it tunnels through it without enough KE to overcome it ?"


Nothing really. The electron exists within the barrier and outside of it at the same time.
 
David Bohm basically formulated the following theory: Reality has 2 things - the wavefunction of all degrees of freedom, and the actuall current position (a classical point in phase space). The wavefunction evolves in time via the ordinary equations of QM, and completely ignores 'the actuall position', while the position evolves accourding to Newton's laws of motion with an addition of a quantum potential which is a non local functional of the wavefunction.

This theory is compatible with all observations of QM, but it doesn't have any new predictions, so it's untestable.

Bohm's answer to Syed's question is therefor that the kinetic energy is positive, but there is negative 'quantum potential' energy.

The answer within the Coopenhagen's interpretation's viewpoint should probably be just that the wavefunction is all that is, and that the tunneling particle never has 'negative kinetic energy'. The kineric energy operator is minus the laplacian, and that's a hermitian operator with a strictly positive spectrum.
 
Those who have read Dirac,Feynmann and the All powerful Wheeler there is a simple answer to the question I have posted earlier concerning the tunneling of an electron through a potential barrier:

We can still observe it but not as an electron but as a positron !
I should like to discuss this.
 
KAZSyed said:
Those who have read Dirac,Feynmann and the All powerful Wheeler there is a simple answer to the question I have posted earlier concerning the tunneling of an electron through a potential barrier:

We can still observe it but not as an electron but as a positron !
I should like to discuss this.


We don't discuss posting based on misinterpretation of basic physics except to say: get an education!
 

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