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A charge is at rest in an inertial reference frame.

Consider this situation:

From the point of view of an observer who is accelerating relative to the charge. Would the observer observe electromagnetic waves generated by the charge?

A few thoughts on this question recently in response to the link given below by joshphysics:

Assuming energy conservation, and considering classical physics, it seems the observer will observe no EM waves -- Since in inertial frame all the energy the charge gets is from its electric field - and it is proportional to $\int\limits_{\text{all space}}(\frac{1}{r^2})^2 \, \mathrm{d}v$ , which is some value/bounded (assuming no point charge), meanwhile assuming there exist EM waves in accelerating frame, the EM waves will have arbitrary energy, as it totally depends on the observer.

If there is EM waves in accelerating frame, Where does the energy come from? It is indeed strange if you input energy to the observer, somehow the charge get the energy and emits it instead.

So I will guess probably no. Once no EM waves in inertial frame, then no EM waves in accelerating frame. (okay, I admit it is kind of appealing to ignorance.)

Pierre Polovodov
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Shing
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1 Answers1

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As you accelerate toward the charge you would observe a time changing electric field which would generate a time varying magnetic field and so on. You can measure this by interacting with the fields using something like an antenna. So yes, in a sense you would observe energy between the charge and your measuring device which is accelerating.

Alex
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