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EM spectrum

  1. Jan 26, 2008 #1
    Are there wavelength limits at either end of the Electromagnetic spectrum? Is it true there could be a wavelength the size of the universe? What happens at the other end? Is there a quantum limit?
  2. jcsd
  3. Jan 26, 2008 #2


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    No limit in either direction.
  4. Jan 26, 2008 #3


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    Pam, the lowest possible theoretical wavelength is zero.
  5. Jan 26, 2008 #4
    Shorter wavelength photons are more energetic, so it requires more and more energy to make them. That's sort of the reason particle accelerators get so huge - it takes tremendous amounts of energy to make particles with short enough wavelengths to probe the tiny length scales that are of interest.
  6. Jan 28, 2008 #5

    Andy Resnick

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    At the upper limit, the longest wavelength (lowest frequency) is set by the size of the universe. At the low end, the smallest wavelength (highest frequency) is set by the Planck energy and corresponds to an energy density at which concepts like "wavelength" break down. I'm sure you can find numbers for each of these easily enough.
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