The discussion centers on the interaction between light, which consists of propagating electric and magnetic fields, and charged particles, particularly focusing on whether there is a magnetic interaction analogous to the electric interaction with charged particles. The scope includes theoretical considerations and interpretations from both classical physics and quantum electrodynamics.
Participants do not reach a consensus; multiple competing views remain regarding the nature of interactions between light and charged particles, with ongoing debate about the clarity of the original question and the validity of various claims made.
Some statements made in the discussion reflect a mix of classical physics and quantum electrodynamics, leading to potential confusion. The original question appears to have ambiguities that contribute to the varied interpretations and responses from participants.
The question in the body is about charged particles but the question in the summary is about photons which are not charged particles, so it’s not completely clear what you’re asking here?jeremyfiennes said:Summary:: Do photons interact with magnetic poles?
Light is propagating electric and magnetic fields. The electric field interacts with electrically charged particles, e.g. electrons. Is there a corresponding magnetic interaction?
This does not look right to me. Do you have any references about these statements?Helena Wells said:Sure if you place a bar magnet in and a light beam passes near the magnet , the bar magnet will experience some force. And if it passes near a current carrying conductor the path of the electrons inside the conductor will be distorted.
Berkeman then said: This does not look right to me. Do you have any references about these statements?Helena Wells said:
Sure if you place a bar magnet in and a light beam passes near the magnet , the bar magnet will experience some force. And if it passes near a current carrying conductor the path of the electrons inside the conductor will be distorted.
Are you thinking of loop antennas and H-fields?Helena Wells said:And if it passes near a current carrying conductor the path of the electrons inside the conductor will be distorted.
The human body affects dipole antennas particularly strongly. This is because in the near field (very close to the antenna), the Electric Fields are particularly strong. Interestingly, the body isn't really magnetic (i.e. does not have a large permeability). Hence, the magnetic fields are not significantly perturbed by the human body, and hence aren't affected like the electric fields are. And because the loop antenna is somewhat the "dual" of the dipole as discussed earlier, the magnetic fields are strong in the near field of the loop antenna. These magnetic fields ultimately give rise to the antenna radiation, and since they are somewhat immune to the human body, loop antennas tend to be much more robust in terms of performance when they are placed near a human. As a result, antennas in hearing aids and other "wearable antennas" are often loop antennas. This property makes loop antennas extremely useful.
Yes sure but one distinction between electric and interaction is there aren't any magnetic monopoles.jeremyfiennes said:My question is rather the other way around. Photons interact with electrically charged particles (e.g. electrons) due to being in part propagating electric fields. Does the same apply to the magnetic aspect. Do photons interact with particles with a magnetic moment due to being in part propagating magnetic fields?
berkeman no the beam of light is made of propagating electric and magnetic which can interact with the electrons inside the conductorberkeman said:Are you thinking of loop antennas and H-fields?
https://www.antenna-theory.com/antennas/smallLoop.php
berkeman and motore are just wrong don't listen to them :)jeremyfiennes said:Berkeman then said: This does not look right to me. Do you have any references about these statements?
Helena Wells' answer was of the kind I was wanting. But it now seems to have been cast into doubt. So ??
Yes it will tend to allign and since the bar magnet will change orientation->it has moved->it has experienced a force which forced it to change orientation.jeremyfiennes said:Helena: But a magnetic dipole will tend to align with a passing magnetic field.
All: I'm after a amgnetic correlate for light photons interacting with electrically charged particles, should there be one. And if there isn't, why not.
You still owe us links to your references on this:Helena Wells said:berkeman and motore are just wrong don't listen to them :)
Helena Wells said:Sure if you place a bar magnet in and a light beam passes near the magnet , the bar magnet will experience some force. And if it passes near a current carrying conductor the path of the electrons inside the conductor will be distorted.
Mr berkeman there aren't links for all the subcases of all the natural phenomena.berkeman said:You still owe us links to your references on this:
But I supplied a link for the case of the loop antenna, which is a real thing.Helena Wells said:Mr berkeman there aren't links for all the subcases of all the natural phenomena.
I don't say it will vibrate I say it will rotate.berkeman said:But I supplied a link for the case of the loop antenna, which is a real thing.
Do you know the typical frequency of "light"? Do you really think that a bar magnet will vibrate at that frequency when you shine light on it?
LOL. Which direction? At what rate?Helena Wells said:I don't say it will vibrate I say it will rotate.
At the direction depending on the polarisation of the photons which make up the light beam.berkeman said:LOL. Which direction? At what rate?
This is incorrect. Yes, photons do interact with electrically charged particles, but this is not due to them "being in part propagating electric fields" - they are no such thing and this confusion is leading us to mix up classical field concepts with quantum electrodynamics.jeremyfiennes said:Photons interact with electrically charged particles (e.g. electrons) due to being in part propagating electric fields.
This question is about electrical and magnetic fields so properly belongs in the Classical Physics section. Magnetic dipoles will move in response to oscillating magnetic fields. NMR is one example, and in principle a bar magnet could be made to oscillate in response to a electromagnetic radiation of sufficiently high amplitude and low frequency (but probably not in practice - the energies and field strengths are not realistic). If this is what OP means by "corresponding magnetic interaction" then the answer is yes.Light is propagating electric and magnetic fields. The electric field interacts with electrically charged particles, e.g. electrons. Is there a corresponding magnetic interaction?
That is a subject for quantum electrodynamics, and it is not clear that there's a B-level answer beyond the one that @vanhees71 offers: "of course in the Compton effect the photon scatters on the electron due to both the electric charge of the electron and its magnetic moment. I however, don't know how to separate these two effects."Do photons interact with magnetic poles?