I How does a nanogenerator work in quantum field theory?

I studied the work of a nano generator in quantu mechanics. The generator uses the principle of triboelectrics. How does this work in quantum field theory?
I think that the electron (wave packet in the field) is in the atom in a small volume because the nucleus inhibits the propagation of the packet. When the contact of two materials occurs, the electron wave packet moves from one atom to another in a localized form under the action of an electromagnetic field, right?
 
Electron is wave packet in field. Can it move from one atom to another?
 
Yes.
 

ZapperZ

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Electron is wave packet in field. Can it move from one atom to another?
This question is puzzling, and odd.

Whether an electron can move from "... one atom to another.. " has nothing to do with "... electron is a wave packet... " or QFT. It has everything to do with whether the electron is in a bound, localized state or not!

Zz.
 
Zz. [/ QUOTE]
This question is puzzling, and odd.

Whether an electron can move from "... one atom to another.. " has nothing to do with "... electron is a wave packet... " or QFT. It has everything to do with whether the electron is in a bound, localized state or not!

Zz.
in quantum field theory, can electrons move from one atom to another atom?
 

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Zz. [/ QUOTE]

in quantum field theory, can electrons move from one atom to another atom?
nikkkom has answered you. Besides, you seem to have not understood my first reply to you, so why should I bother?

Zz.
 
nikkkom has answered you. Besides, you seem to have not understood my first reply to you, so why should I bother?

Zz.
excuse me, does the electron go from atom to atom like a wave packet?
 
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Quantum field theory is a more general version of quantum mechanics, in the limit of low energies they make the same predictions. Using quantum field theory to describe atomic processes is possible in principle but it is way too complicated in practice. It is like trying to describe the motion of a car on a highway with general relativity. Possible? Yes. But you need a week for the easiest processes where you can get a solution with Newtonian mechanics in a minute. Why would you want to do that?
 
The question is asking how you describe ionization or electron transfer in QFT.
 

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The question is asking how you describe ionization or electron transfer in QFT.
Let's note that even that is vague.

For example, in covalent bonding, electrons are shared between 2 atoms. So is this an "electron transfer" that goes back and forth? In tight-binding approximation, we have the "hopping" parameter "t" that corresponds to the overlap of the wavefunction between neighboring ions. Is this an "electron transfer"? In the conduction band, we have the Bloch wavefunction of the conduction electrons as they move across periodic lattice potential. Is this an "electron transfer"?

In all of those, one can easily be mistaken into thinking that these are electrons moving from one atom to another.

I'd like to know if the OP has similar issues in using the 'non-QFT' Hamiltonian, especially considering that one can often rewrite such Hamiltonian using Second Quantization.

Zz.
 
Quantum field theory is a more general version of quantum mechanics, in the limit of low energies they make the same predictions. Using quantum field theory to describe atomic processes is possible in principle but it is way too complicated in practice. It is like trying to describe the motion of a car on a highway with general relativity. Possible? Yes. But you need a week for the easiest processes where you can get a solution with Newtonian mechanics in a minute. Why would you want to do that?
I would like to know if an electron can move from one atom to another in quantum field theory
 
Let's note that even that is vague.

For example, in covalent bonding, electrons are shared between 2 atoms. So is this an "electron transfer" that goes back and forth? In tight-binding approximation, we have the "hopping" parameter "t" that corresponds to the overlap of the wavefunction between neighboring ions. Is this an "electron transfer"? In the conduction band, we have the Bloch wavefunction of the conduction electrons as they move across periodic lattice potential. Is this an "electron transfer"?

In all of those, one can easily be mistaken into thinking that these are electrons moving from one atom to another.

I'd like to know if the OP has similar issues in using the 'non-QFT' Hamiltonian, especially considering that one can often rewrite such Hamiltonian using Second Quantization.

Zz.
Are you saying that in quantum field theory, an electron cannot move from one atom to another?
 

ZapperZ

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Are you saying that in quantum field theory, an electron cannot move from one atom to another?
No, I did not say that.

How about you answer MY question: are you familiar with the standard QM, and Second Quantization?

Zz.
 
No, I did not say that.

How about you answer MY question: are you familiar with the standard QM, and Second Quantization?

Zz.
I am familiar only with quantum mechanics.
So say that in a quantum field theory an electron can move from one atom to another, for example in a triboelectrical effect? In quantum mechanics, this was described by the movement of the wave packet.
 

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I am familiar only with quantum mechanics.
So say that in a quantum field theory an electron can move from one atom to another, for example in a triboelectrical effect? In quantum mechanics, this was described by the movement of the wave packet.
And in tight-binding approximation, it is NOT described by "... movement of the wave packet...". That is the point that you seem to have trouble understanding. The concept of electrons going from one atom to another is VAGUE because there can be MANY different types and mechanism! I gave several different examples above, and you didn't seem to comprehend the significance in their differences!

If you have a specific phenomenon that you want this, then you should clearly describe it, rather than making an over-generalized description of "electrons going from one atom to another". Secondly, do you have the Hamiltonian to describe it in the usual quantum description? If you do, then you need to look up "Second Quantization", because this is what is involved in the QFT formulation. QFT is NOT something different!

Zz.
 
And in tight-binding approximation, it is NOT described by "... movement of the wave packet...". That is the point that you seem to have trouble understanding. The concept of electrons going from one atom to another is VAGUE because there can be MANY different types and mechanism! I gave several different examples above, and you didn't seem to comprehend the significance in their differences!

If you have a specific phenomenon that you want this, then you should clearly describe it, rather than making an over-generalized description of "electrons going from one atom to another". Secondly, do you have the Hamiltonian to describe it in the usual quantum description? If you do, then you need to look up "Second Quantization", because this is what is involved in the QFT formulation. QFT is NOT something different!

Zz.
for example a triboelectric where an electron must move from one atom to another under the action of an electromagnetic field? Is this possible in quantum field theory?
 

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for example a triboelectric where an electron must move from one atom to another under the action of an electromagnetic field? Is this possible in quantum field theory?
Is it possible in quantum mechanics?

Zz.
 
Is it possible in quantum mechanics?

Zz.
Yes it is possible in QM but i don't understand about QFT because in quantum field theory, a virtual photon is used in electromagnetic interaction.Thank you
 
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What happens? What you ask does not happen, so what are you asking about now?
I asked "can field quanta (electron) move from one atom to another?" Thank you
 
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I asked "can field quanta (electron) move from one atom to another?"
And this question, as you ask it, is too vague to answer. Various suggestions have been made in this thread about how to make your question more precise so it can be answered. You don't seem to have the background to grasp any of these suggestions, so further discussion is unlikely to be helpful. You basically seem to be asking for someone to explain QFT to you, and that is much too broad for a PF discussion; you need to learn QFT from a textbook.

Thread closed.
 

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