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How can electrons form a wave?

  1. Aug 19, 2014 #1
    an air wave takes place in volumes of air, water takes place in volumes of water... but u can have an electromagnetic wave go through empty space using only one particle. how does this work? this to me does not seem analogous to the waves that i am used to. does this "wave" instead refer to the electromagnetic charge of the particle or something?
  2. jcsd
  3. Aug 19, 2014 #2


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    Let's say a charge is accelerating through free space. From one instant of time to the next, the electromagnetic field the charge carries will change at the location of the charge. But the electromagnetic field of the charge stretches throughout all of the space while at the same time being relativistic so its local change from one instant to the next has to propagate out to spatial infinity at some finite speed akin to a disturbance in an elastic body. This propagation is electromagnetic radiation. Scroll down in the following document until you see the section on radiation: http://physics.weber.edu/schroeder/mrr/MRRtalk.html

    But keep in mind an important point: the radiation propagates out to spatial infinity independently of the charge in the sense that it "detaches" itself from the charge. The key difference between the near-zone electromagnetic field of the charge and the radiation field is the latter does not die out fast enough by the time it reaches the far-zone ("wave-zone").

    This is not unlike the sound waves that propagate throughout the entirety of a solid by means of successive vibrations of atoms in lattice sites when you say disturb the solid by punching it at a single point.
    Last edited: Aug 19, 2014
  4. Nov 7, 2014 #3
    thx i get it now ur description was very helpful
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