Radiation of an accelerated charge

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SUMMARY

The discussion centers on the radiation emitted by an accelerated charge, particularly an electron in a capacitor's electric field. It is established that an accelerated charge radiates photons, but the emission is not continuous due to quantum mechanics principles. The participant questions the nature of the electric field and the directionality of emitted photons, suggesting that the radiation has a certain symmetry rather than randomness. The conversation highlights the distinction between classical electromagnetism and quantum field theory (QFT) in understanding these phenomena.

PREREQUISITES
  • Quantum Mechanics (QM) fundamentals
  • Electromagnetism (EM) principles
  • Quantum Field Theory (QFT) concepts
  • Heisenberg's Uncertainty Principle
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  • Study the quantization of the electric field in Quantum Field Theory (QFT)
  • Explore the relationship between acceleration and photon emission in Quantum Electrodynamics (QED)
  • Learn about the classical versus quantum treatment of electromagnetic radiation
  • Investigate the implications of the Heisenberg Uncertainty Principle on particle behavior during acceleration
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Students and professionals in physics, particularly those focusing on quantum mechanics, electromagnetism, and quantum field theory, will benefit from this discussion.

fluidistic
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I'm asking this question in the quantum physics part because I'd like a quantum related answer.
When a charge is accelerated, it will radiate photons. In my belief, it must radiate continuously as long as it's accelerated.
Maybe I'm getting a wrong picture. Imagine an electron moving through empty space between 2 opposite charged plates (capacitor). It will be accelerated toward one plate. But since I had not took any serious quantum course, I don't know if the E field between the plate is really continuous or made of EM waves or whatever I can imagine. Thus I'm not 100% sure if the electron will be accelerated at any moment, or by quanta. If it is accelerated at any moment, it should emit continuously I believe... Producing infinitely many photons, which doesn't occur obviously. Therefore I'm missing someting.
Another question: When a charge is accelerated very shortly, its speed will increase, it will emit at least 1 photon... but in what direction? Is that random? Or opposite to the direction motion of the accelerated particle, so that the speed of the charge gets lower than the speed it had right after the acceleration? And if so, is the speed of the particle the same as it was before the acceleration? If so, it would mean that the energy required to accelerate the electron has been 100% converted into a single photon and that the electron's motion remains unchanged... But with Heisenberg's uncertainty principle, I guess I'm far from guessing things right.

I'd appreciate any comment or any link/name of textbooks on the subjet.
Thanks a lot.
 
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Greg Bernhardt said:
@fluidistic did you find any more insight on this topic?
Yes, I completed all the undergraduate courses, including QM and EM. I don't have the books (Zangwill & Jackson) at hand to answer my questions right now.
My intuition regarding my last question tells me that the radiation will have a certain rotational symmetry and will not point randomly nor in a sharp direction.

Otherwise I seem to confuse a classical treatment of an electron with a QM or QFT treatment.

About the quantization of the E field, in QM I dealt with classical E field, but I think it can be quanticized in QFT.
 
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