Oscillating charged particles and E.M waves

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Discussion Overview

The discussion revolves around the behavior of oscillating charged particles and the generation of electromagnetic (E.M.) waves, particularly from the perspective of an observer oscillating in parallel with the charged particle. Participants explore the implications of different frames of reference and the detection of E.M. radiation.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant questions whether an observer oscillating with the charged particle would detect E.M. waves, given that the particle appears at rest from their perspective.
  • Another participant suggests that while the observer may find it difficult to detect the waves, other radio devices would still function, indicating the presence of E.M. waves.
  • A participant expresses confusion about the implications of radio detection in the context of the observer's motion.
  • It is noted that in an accelerating frame, the rules regarding radiation emission differ from those in inertial frames, suggesting that the observer may still detect radiation.
  • One participant emphasizes that the motion of the charged particle and the observer is presumed to be below the speed of light, which may simplify the analysis.
  • There is a discussion about how radio waves are detected through the motion of electrons in a wire, and how oscillations could still lead to a response from a receiver.

Areas of Agreement / Disagreement

Participants express differing views on whether an observer in a non-inertial frame can detect E.M. radiation from an oscillating charge. Some argue that detection is possible despite the observer's frame, while others question the implications of being at rest relative to the charge.

Contextual Notes

The discussion includes assumptions about the nature of motion (inertial vs. non-inertial) and the conditions under which E.M. waves can be detected. There are unresolved aspects regarding the specifics of how detection occurs in different frames.

Slimy0233
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TL;DR
Effect of parallel motion and observation in parallel motion concerning oscillating charged particles
If I were to tie a friend of mine adjacent to the oscillating charge and make him oscillate in parallel to my oscillating charged particle such that to him the oscillating particle is at rest, would he observe the generation of electromagnetic waves.
 
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Sure. You might make it difficult for him to detect if you get the phase of his oscillation right, but nobody else's radios are going to stop working just because you're shaking him around.
 
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Ibix said:
but nobody else's radios are going to stop working just because you're shaking him around.
I am sorry, I don't understand this, the radios thing.

Also, I get a feeling that you are saying he would be able to detect those oscillations? I mean, it's literally at rest from his perspective. So, I was just wondering how?
 
Slimy0233 said:
I mean, it's literally at rest from his perspective.
In a frame that is accelerating...
 
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DrClaude said:
In a frame that is accelerating...
sorry Dr, but what's your point? please explain
 
Slimy0233 said:
I am sorry, I don't understand this, the radios thing.
Well, if there's a source of radio waves then radio detectors will be able to detect them. Even if your friend's radio is disabled by circumstance, he can still hear other radios detecting the waves, so he knows they're there. And he can tell he's oscillating using accelerometers, so even assuming that the oscillation disables the radio he can correct for it and make his radio inertial.
Slimy0233 said:
Also, I get a feeling that you are saying he would be able to detect those oscillations? I mean, it's literally at rest from his perspective. So, I was just wondering how?
You detect radio waves using the motion of electrons in a wire under the changing electromagnetic field of the wave. If you oscillate the wire I think you will cause the electrons to oscillate along with it, and they will be further accelerated by the electromagnetic field of the wave. So I think you'll still get a response from the receiver.

Remember that your friend can detect whether he is moving inertially or not in an absolute sense. So he can tell whether the charged particle holding position infront of his nose is moving inertially or not. It is, therefore, not at all obvious that he shouldn't expect EM radiation.
 
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The motion of the two is presumed to be far below the speed of light so relativity does not come into it.
In this case the radiation from one, when it reaches the other, will be detectable.
 
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Slimy0233 said:
sorry Dr, but what's your point? please explain
You seem to be thinking that in the frame where he particle is at rest, since it is at rest and not accelerating, it cannot emit radiation. But that is only true for particles at rest in inertial frames.
 
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DrClaude said:
You seem to be thinking that in the frame where he particle is at rest, since it is at rest and not accelerating, it cannot emit radiation. But that is only true for particles at rest in inertial frames.
thank you very much for explaining that.
 
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Ibix said:
Well, if there's a source of radio waves then radio detectors will be able to detect them. Even if your friend's radio is disabled by circumstance, he can still hear other radios detecting the waves, so he knows they're there. And he can tell he's oscillating using accelerometers, so even assuming that the oscillation disables the radio he can correct for it and make his radio inertial.

You detect radio waves using the motion of electrons in a wire under the changing electromagnetic field of the wave. If you oscillate the wire I think you will cause the electrons to oscillate along with it, and they will be further accelerated by the electromagnetic field of the wave. So I think you'll still get a response from the receiver.

Remember that your friend can detect whether he is moving inertially or not in an absolute sense. So he can tell whether the charged particle holding position infront of his nose is moving inertially or not. It is, therefore, not at all obvious that he shouldn't expect EM radiation.
hey... thank you again! that's very helpful!
 

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