QED & In-Ground Electrons: Why No Photon Emission?

In summary, the concept of ground state in quantum mechanics means that an electron is at its lowest possible energy level and cannot emit a photon without absorbing one first. The phenomenon is explained by Quantum Electrodynamics, where the atom as a whole is involved in the emission or absorption of photons in order to conserve both energy and momentum. While the electron may not appear to be doing anything in the ground state, it is still coupled to the Quantum EM field and can absorb photons. This concept highlights the need for Quantum Field Theory in understanding the behavior of particles and fields at a more advanced level.
  • #1
fxdung
388
23
In ground state electron does not emit photon.Can we use QED to explain why in ground state electron does not emit any photons?
 
Physics news on Phys.org
  • #2
When it's in the ground state it isn't doing anything so why SHOULD it emit photons?
 
  • #3
Follow QED electrons would always be possible to emit photons even in ground state of atom. But in fact atom is stable.Thus why I ask the question.
 
  • #4
fxdung said:
Follow QED electrons would always be possible to emit photons even in ground state of atom.

Why do you think this is true? Do you understand what "ground state" means?
 
  • #5
I would like use QED to demonstrate the existence of ground state.
 
  • #6
fxdung said:
I would like use QED to demonstrate the existence of ground state.

That's a different question from the question of why an electron does not emit a photon when it is in the ground state. You can start a separate thread if you want to discuss that question. If you aren't convinced that a ground state exists, for an electron or anything else, then your question in the OP of this thread makes no sense and we can just close this thread.
 
  • #7
fxdung said:
Can we use QED to explain why in ground state electron does not emit any photons?
If it could emit a photon then it wouldn’t be the ground state, by definition. By the way, it is not the electron that emits the photon, it is the atom. And it is not the electron that is in the ground state, it is the atom.
 
  • Like
Likes vanhees71
  • #8
I think electron would emit photon because nucleus too heavy to motion to radiate(?)
 
  • #9
fxdung said:
I think electron would emit photon because nucleus too heavy to motion to radiate(?)
An electron cannot emit a photon, it would not be able to conserve both energy and momentum. It has to be the atom as a whole in order to conserve both. This is a fairly straightforward exercise to calculate for yourself. I recommend it.
 
  • Like
Likes vanhees71 and bhobba
  • #10
phinds said:
When it's in the ground state it isn't doing anything so why SHOULD it emit photons?

Your answer is a very common view of it, and indeed would likely get full marks in an introductory QM course, at least I would give it full marks, but a more advanced look at it shows what is going on is more subtle.

It will not emit a photon because its in the lowest state it can go. However it is still doing 'something' because it's not in a stationary state as its coupled to the Quantum EM field that permeates all of space which is why it can still absorb photons. If its not in the ground state, but an excited state, again while supposedly in a stationary state, it isn't really, but as previously mentioned coupled to the Quantum EM Field. Again the electron and EM field, as a system, will change with time, and it will eventually emit a photon, or perhaps even absorb another one.

Their seems to be a lot of queries along these lines at the moment, so I will start a new thread with the full answer and associated detail. Excellent introduction to why we need Quantum Field Theory as well.

Thanks
Bill
 
  • Like
  • Informative
Likes vanhees71 and phinds

FAQ: QED & In-Ground Electrons: Why No Photon Emission?

What is QED and how does it relate to in-ground electrons?

QED stands for Quantum Electrodynamics, which is a theory that explains the interactions between electromagnetic fields and charged particles, including electrons. In-ground electrons are electrons that are located within the Earth's crust. QED helps us understand the behavior of these electrons and their interactions with other particles.

Why do in-ground electrons not emit photons?

In-ground electrons do not emit photons because they are in a stable state. According to QED, electrons can only emit photons when they are in an excited state, meaning they have absorbed energy and are in a higher energy level. In-ground electrons are in a lower energy state and do not have enough energy to emit photons.

How does the concept of virtual particles explain the lack of photon emission from in-ground electrons?

According to QED, virtual particles are constantly popping in and out of existence in the vacuum of space. These virtual particles can interact with particles like electrons, causing them to emit or absorb energy. However, in the case of in-ground electrons, these virtual particles do not have enough energy to cause the electrons to emit photons. Therefore, the lack of photon emission can be explained by the absence of high-energy virtual particles in the Earth's crust.

Can in-ground electrons ever emit photons?

Yes, in-ground electrons can emit photons under certain conditions. For example, if an external energy source, such as a high-energy particle, collides with an in-ground electron, it can transfer enough energy to the electron to put it in an excited state and cause it to emit a photon. However, in the absence of such external energy sources, in-ground electrons will not emit photons.

How does QED help us understand the behavior of in-ground electrons?

QED provides a mathematical framework for understanding the interactions between particles and electromagnetic fields, including in-ground electrons. By using this theory, scientists can make predictions about the behavior of in-ground electrons and test them through experiments. QED also helps us understand why in-ground electrons do not emit photons and how they interact with other particles in their environment.

Similar threads

Replies
15
Views
3K
Replies
19
Views
2K
Replies
3
Views
1K
Replies
21
Views
2K
Replies
4
Views
2K
Replies
3
Views
1K
Back
Top