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Matter waves

  1. Feb 15, 2016 #1
    De Broglie's postulate states that λ=h/p and ƒ=E/h. If you plug in E=pc, then you get λ=c/ƒ. Using the equation for wavelength λ=v/ƒ, I found that v=c, but this can't be true, because the matter waves would be traveling a c. What did I do wrong? Thanks!
  2. jcsd
  3. Feb 15, 2016 #2


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    E=pc holds only for massless particles. You have obtained that massless particles propagate at the speed of light. But that is obvious.
  4. Feb 15, 2016 #3
    So do I need to factor in mc^2 too?
  5. Feb 16, 2016 #4


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    Staff: Mentor

  6. Feb 16, 2016 #5
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