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Electromagnetic radiation

  1. Dec 31, 2007 #1
    What is the mechanism that operates behind the production of electromagnetic radiations when charged particles are accelerated?

    How are electromagnetic radiations produced in this way?
  2. jcsd
  3. Dec 31, 2007 #2


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    It seems our understanding of electromagnetic phenomena can be encapsulated in Maxwell's equations and the relativistic extensions. There's nothing about 'how' the radiation is produced in this. Since quantum theory some models based on vacuum polarization have been utilised.

    There is an experiment called PVLAS going on ( or finished) in Italy which is looking for dichroism in light going through a strong magnetic field. If this effect is found, it will give weight to the vacuum polarization theories.

    Maybe someone else can pick this up...

    [edit] I just noticed the word 'accelerated' in the question, so my reply might be bit off-beam.
    Last edited: Dec 31, 2007
  4. Jan 1, 2008 #3
    The EM radiation produced by accelerated charges is troubling my head. Consider the following case.

    The principle of synchrotron and cyclotron is based on the fact that the charged particles take up circular path in magnetic feilds. In a circular path the body is under the state of acceleration. So it would emit radiation. As a result, its energy would decrease. Therefore after a certain period of time the energy of the particle would decrease instead of increasing which was the primary goal. Then how does these devices simplify our task.

    Similar conversation also applies to a Bhor Atom. As the electron goes around the nucleus its energy would continue to decrease and collide with the nucleus. But I think I have an answer for this. Bhor's Theory also suggessts that energy of an electron is quantised. So it should not have energy less than -13.6eV. That prevents the electron from colliding with the nucleus. Am I right?
  5. Jan 1, 2008 #4


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    Since Bohr's bold step in assuming that the energy levels of atoms are quantised, a new theory call 'Quantum Mechanics' was developed which is able to predict correctly the energy levels of the hydrogen atom. In this theory the actual movement ( if any ) of the electron is not specified but a probability distribution is given.

    Try looking up Schrodingers equation or quantum mechanics in some books.
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