EM Field Angular Momentum Emission Without Emitting Energy?

AI Thread Summary
The discussion centers on the conditions under which electromagnetic (EM) angular momentum can be emitted into space without corresponding energy loss. It highlights that the Poynting vector must decrease in a specific manner to avoid energy radiation. Kevin M. suggests that applying torque to a magnetic field can transfer angular momentum to the EM field, but this is more about absorption than emission. The conversation also touches on the concept of photons, noting that they cannot possess momentum without energy. The Unruh effect is mentioned as a potential framework for understanding these phenomena.
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To radiate energy, the Poynting vector must not drop faster than with the inverse square of the distance. Under what circumstances can EM angular momentum be emitted to the vacuum of space (i.e. without being recovered via inductive coupling) and yet not lead to energy losses through radiation? Is it possible?
Kevin M.
 
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Say there is a magnet. We bring charge from infinite distance and put it on magnet. Magnetic field give Lorentz force to the charge so we give torque to the field. Thus angular moment is put to electromagnetic field. This is an absorption not a emission but the reverse process, i.e. discharge from charged magnet might be of your interest. Best regards.
 
I am not sure at all here, but thinking in terms of photons, its like you want a photon to possesses momentum but not energy which simply is not possible.
 
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Hello

Well... I don't want to full your head with hot air (my mother-language is not English, I don't know if the idiom is correct), but you may take a look to this
https://en.wikipedia.org/wiki/Unruh_effect

Unruh derived the effect assuming linear acceleration; I think that it is still correct for centripetal.

Greetings.
 
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