The magnetic field of a photon

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Discussion Overview

The discussion revolves around the nature of the magnetic field associated with photons of varying frequencies and energies. Participants explore whether different photons exhibit the same magnetic field characteristics, considering both classical and quantum perspectives.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants question whether it is valid to describe photons, which are quantum particles, using classical notions like magnetic fields.
  • There is a discussion about the variability of magnetic fields with time, suggesting that higher frequency photons have magnetic fields that change more rapidly.
  • One participant notes that while photons have different linear momentum, they all share the same angular momentum, raising questions about the implications of this similarity.
  • Another participant emphasizes the need to treat electromagnetic phenomena according to the context, suggesting that photons should not be strictly classified as particles or waves.
  • Some participants express skepticism about achieving consistency in describing photon characteristics within the limitations of language.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the nature of the magnetic field of photons, with multiple competing views and ongoing debate about the appropriateness of classical descriptions in a quantum context.

Contextual Notes

Participants highlight the limitations of classical descriptions when applied to quantum phenomena, indicating unresolved issues regarding definitions and the nature of electromagnetic fields.

bobie
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Do different photons with different frequencies/energies have same magnetic field?
Does the fact that all photons have same magnetic angular momentum imply a positive answer?
 
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bobie said:
Do different photons with different frequencies/energies have same magnetic field?

What do you mean by 'the same'? The magnetic field also varies with time, so higher frequency photons have magnetic fields which vary faster over time.
 
I'm not sure it is even a valid thing to try to describe a quantum particle in terms of a classical notion like a field.
I realize that may be an annoying answer but you may need to accept it.
 
Drakkith said:
What do you mean by 'the same'? The magnetic field also varies with time, so higher frequency photons have magnetic fields which vary faster over time.
The question was rhetorical of course, different photons have different linear momentum hf/c, why should the all have same angular momentum = 0.159 h ?
 
bobie said:
The question was rhetorical of course

Rhetorical, or pointless?
 
sophiecentaur said:
I'm not sure it is even a valid thing to try to describe a quantum particle in terms of a classical notion like a field.
I realize that may be an annoying answer but you may need to accept it.
Funny thing is that we also have lots of threads where we explicitly NOT want the photon described as a particle (e.g. here), because it isn't .

Even after all these years I kind of like to keep an open mind and be satisfied that we all we can do is describe a big part of the behaviour of a photon in terms we also use for particles. And a (perhaps bigger :smile:) part in terms of electromagnetic fields, quantum states and what else humanity has come up with over the years. But then, I'm only an experimental physicist...[edit] oh, and bobie: I think the answer to your question has to do with the coupling of E and B field for an electromagnetic wave. I need to re-read big parts of Jackson before I can really answer, so I'm glad to be watching this thread. Who knows what may be added yet !
 
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BvU said:
Funny thing is that we also have lots of threads where we explicitly NOT want the photon described as a particle (e.g. here), because it isn't
I think the problem here is that you / they are assuming that the EM phenomenon is 'in fact' particulate. That approach is bound to bring in difficulty because a classical Field has to be 'somewhere' and relate to a position and extent. When you have a photon that is nowhere, in particular, until it is interacting with matter (that's the quantum aspect) you can't talk in terms of the fields. That applies even when discussing a quantity like angular momentum
You have to treat the EM phenomenon according to the situation you are studying. It's more than just the old Duality thing that we learned in the beginning of our Advanced Physics courses. So it is not sense to want to describe a photon NOT as a particle. You need to step back and choose to describe EM as particle or wave - those are the options.
Drakkith said:
The magnetic field also varies with time, so higher frequency photons have magnetic fields which vary faster over time.
I am surprised at your making that comment in the light of many of the comments you have made in the past which imply a distinct nature between the two approaches - but here, you appear to bolt them together again. ?? :confused:
 
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sophiecentaur said:
I am surprised at your making that comment in the light of many of the comments you have made in the past which imply a distinct nature between the two approaches - but here, you appear to bolt them together again. ?? :confused:

I don't think there's any way of getting consistency AND general applicability into an English-language handwave about photon characteristics...
 
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sophiecentaur said:
I am surprised at your making that comment in the light of many of the comments you have made in the past which imply a distinct nature between the two approaches - but here, you appear to bolt them together again. ?? :confused:

o:)
 
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Drakkith said:
o:)
I think Nugatory has summed up the situation so far. :biggrin: (No egg on any faces here)
 

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