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Magnets in vacuum

  1. Sep 23, 2011 #1
    Hello, sorry for bad english.

    I have probably a very stupid question :)

    Let's place two magnets in vacuum (empty space)
    How does one magnet "know" of the other one, if there is "nothing" between them?
    How "nothing" that exists between them can interact with magnets?
    I know of course that there is a "field" between them, but if the field exist there is no more "nothing" there ?
  2. jcsd
  3. Sep 23, 2011 #2
    Yes, the field is contained in the space.
  4. Sep 23, 2011 #3


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    Gold Member

    the magnetic field between magnets is not carried by or in the air between them, so why would it surprise you that removing the air would have no effect on the field?
  5. Sep 26, 2011 #4
    The interaction is carried by the energy in the magnetic field...electromagnetic fields do not require particles to vibrate like,say, sound waves do.

    In fact all four fundamental forces (strong, weak, electromagnetic, gravitational) do NOT require any intermediate entity, like air or particles....they produce their own particles...or waves....and these convey the energy of interaction.
  6. Sep 26, 2011 #5
    Virtual photons can be postulated to convey how magnets "know" that other magnets exist. This knowledge cannot be acquired faster than the speed of light in vacuum, which is the speed that photons - virtual or not - travel. This has nothing to do with air, water, or any other medium between the magnets, so magnetic fields still exist even in a complete vacuum (whatever that really means).
  7. Sep 26, 2011 #6
    Vacuum just means that there is no air (or as little air as physically possible). Vacuum's can still contain electromagnetic fields, gravitational fields, vacuum fluctuations.
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