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Wavelength of matter at rest

  1. Jan 8, 2010 #1
    if de Broglie's equation: wavelength = h/(mv) works allways, then what is the wavelength of an object at rest (v=0) is it undefined or infinity or something?
  2. jcsd
  3. Jan 9, 2010 #2


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    Staff: Mentor

    Because of the uncertainty principle, you can't have a wave function for a particle that is definitely exactly at rest, just as it can't have any other definite exact value of momentum (and velocity).

    The best you can do for a "stationary" particle is a wave packet whose momentum has an expectation value of zero, and includes waves with both positive and negative values of momentum, in a range that is centered on zero. I suspect that such a wave packet would be a standing wave with maximum amplitude at the most likely location of the particle, and decreasing to zero in either direction so the width and the momentum range satisfy the uncertainty principle.
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