Photon Exchange - Frequency? And uncharged antiparticles

In summary, the conversation covers the topic of photon exchange mechanism, with the individual wondering about the analogy used in class and whether or not photons have a frequency of 0. They also ask about the attraction between neutrally charged particles and the concept of virtual photons. The conversation touches on topics such as QED, photon characteristics, and the composition of neutrons and antineutrons.
  • #1
MrNerd
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0
I wondered about the photon exchange mechanism when my AP physics teacher taught about it. Essentially, it's like shooting a basketball back and forth. I don't see the attractive part, but's that what the analogy was on the internet thing used. I assume it's in the math, anyway.

But my main question is, do these photons have a frequency of 0? In order to be constant repel or attract, would the photon not have to see on the same cycle to keep the charge correct(EM radiation is a cycling electric field, oscillating between positive and negative). To be constantly positive or constant negative, the photon would have to not oscillate, hence 0 Hz. The main contradiction with accepting this is that photons ARE oscillations in the electric field(magnetic arises from the changing electric, I believe), causing EM radiation. So am I envisioning in incorrectly, or can photons sometimes have frequency and sometimes not have frequency, depending on the source?

Since I'm also in the quantum mechanics section, which covers antimatter(I think), what is it that attracts neutrally charged particles/antiparticles together, like a neutron/antineutron pair? I think I've read somewhere that neutrons are polarized somehow, so this is the only thing I can think of, aside from the other opposite features attracting(like quarks or the other things)

Thank you for your help.
 
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  • #2
MrNerd said:
I wondered about the photon exchange mechanism when my AP physics teacher taught about it. Essentially, it's like shooting a basketball back and forth. I don't see the attractive part, but's that what the analogy was on the internet thing used. I assume it's in the math, anyway.

For the question about attraction have you ever read http://math.ucr.edu/home/baez/physics/Quantum/virtual_particles.html"
 
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  • #3
MrNerd said:
I wondered about the photon exchange mechanism when my AP physics teacher taught about it. Essentially, it's like shooting a basketball back and forth.
That analogy is completely false. You need to use the mathematics of QED.
 
  • #4
As Clem posted, the details of electromagnetic interactions go way beyond photon characteristics.

Photons have different frequencies depending on their energy...E = hf...

So a photon from one frequency (color) of light will exhibit a different energy from a photon of another color...gamma rays, for example, are very high energy high frequency...

Check the first few paragraphs here: http://en.wikipedia.org/wiki/Photon

and skip down to see PHYSICAL PROPERTIES.

Not also that photons DO exhibit wave particle duality...

You can also check:
http://en.wikipedia.org/wiki/Electromagnetic_radiation#Particle_model
 
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  • #5
Since I'm also in the quantum mechanics section, which covers antimatter(I think), what is it that attracts neutrally charged particles/antiparticles together, like a neutron/antineutron pair? I think I've read somewhere that neutrons are polarized somehow, so this is the only thing I can think of, aside from the other opposite features attracting(like quarks or the other things)

A neutron is only neutral overall. It is composed of 3 quarks, of which 1 of them has a charge of + 2/3 and the other 2 have charges of - 1/3. An antineutron would actually be composed of an anti-upquark and 2 anti=downquarks. It is a similar situation like (but not exactly like) an anti-hydrogen atom contacting a normal hydrogen atom I believe. I don't believe that a neutron and antineutron would attract each other from a distance, but if they do get close enough to contact then they should annihilate.
 
  • #6
Ah, so a virtual photon is like the ball passing only for repulsion, but for attraction, the photon goes away from the attracted/ing object and back in time, enabling it to be absorbed by the other particle. This seems certainly plausible considering the bizarrely twisted logic(at first glance, at least) of quantum mechanics.

For the uncharged antimatter pair then, they aren't attracted. I assume they can't be captured or used or whatever because they can't be stopped electromagnetically from flying into normal matter in their path.

Thanks for the help
 
  • #7
Ah, so a virtual photon is like the ball passing only for repulsion, but for attraction, the photon goes away from the attracted/ing object and back in time, enabling it to be absorbed by the other particle. This seems certainly plausible considering the bizarrely twisted logic(at first glance, at least) of quantum mechanics.
That is bizarre all right, but neither plausible nor correct. And yet that is exactly what John Baez said, isn't it. :frown: John is an excellent mathematician, but this explanation of his of Coulomb attraction/repulsion is completely made up, and I can only suggest you look elsewhere.
 

1. What is photon exchange and how does it relate to frequency?

Photon exchange is a process in which two particles interact by exchanging a virtual photon. This interaction is responsible for the electromagnetic force between particles. Frequency, on the other hand, refers to the number of cycles a wave completes in a given amount of time. In photon exchange, the frequency of the virtual photon determines the strength of the interaction between particles.

2. Can uncharged particles participate in photon exchange?

Yes, uncharged particles can participate in photon exchange. This is because the virtual photon is a carrier of the electromagnetic force, which can act on both charged and uncharged particles. However, the strength of the interaction may differ depending on the charge of the particles involved.

3. What is the relationship between photon exchange and the electromagnetic force?

Photon exchange is the mechanism by which the electromagnetic force is transmitted between charged particles. When two particles interact by exchanging a virtual photon, they experience a force that is either attractive or repulsive depending on their charges.

4. How does the frequency of the virtual photon affect the strength of the electromagnetic force?

The frequency of the virtual photon is directly proportional to the strength of the electromagnetic force. This means that the higher the frequency of the virtual photon, the stronger the force between the interacting particles will be.

5. Can antiparticles participate in photon exchange?

Antiparticles can participate in photon exchange just like regular particles. However, the virtual photon exchanged between antiparticles may have opposite charge compared to the one exchanged between regular particles. This results in a repulsive force between antiparticles, whereas regular particles may experience an attractive force.

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