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Electromagnetic Energy propagation

  1. Apr 13, 2010 #1
    Hi All

    Is the following statement true:

    Electromagnetic energy requires a wave medium to propagate. (The way free electrons in a copper conductor transfer energy in an AC circuit. Electrons can act as wave medium).

    If it is true, How does EM energy travel in space. Can gravity act as a wave medium?
  2. jcsd
  3. Apr 13, 2010 #2
    EM energy travels via vacuum through space. Gravity itself is propagated in waves and light is curved because of said gravitational fields. As for EM radiation needing a medium to propagate, what you are speculating is luminiferous ether, which was thought to exist for centuries because waves had only been seen to move though some sort of medium.The thought was that if light traveled constantly at c through a light medium, then a light medium must exist throughout the universe, for light to move through all space. This view was successfully disproved by an experiment done by Michelson and Morley. The specifics and results can be found here http://scienceworld.wolfram.com/physics/Michelson-MorleyExperiment.html.
  4. Apr 13, 2010 #3
    Electromagnetic radiation do not need a medium to travel into.

    It can be deduced from the Razor's law, that electromagnetic wave do no need a medium to travel, following the Michelson-Morley experiment.

  5. Apr 13, 2010 #4
    Thank you all for the clarification
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