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Homework Help: De Broigle's equation for matter wave and slowing down an object

  1. May 14, 2009 #1
    De Broigle's equation for "matter wave" and slowing down an object

    I was reading the wave-particle duality and there are is something I don't understand:

    Can you slow down an object enough for it to start behaving as a wave ?

    ej: let's say I weight 81 kg and I want to behave as a wave of λ = 600nm(yellow light) then according to De Broigle's equation :
    v = h / mλ
    v = (6.626068 * 10^-34) / (81 * 6.0 * 10^-7) = 1.36338848 × 10-29 m/ s

    Now, is this possible ? does the velocity have to be absolute or can I have wave behaviour for a given frame of reference?

    Meaning, let's say I start running from rest until I reach a velocity of 8 km/h, then, there was a point in time where I had to have the required velocity to behave as a wave for the given λ, at least to the observers that were on my same frame of reference.

    Or does it have to be absolute ?

    Meaning, I have to take into account the velocity of my planet as it goes around the sun, plus the solar system as it goes around the center of the galaxy, and the galaxy as it moves towards some point in the universe.

    Do such places exist, where the velocity of an object is so slow that I could behave as a wave ?
  2. jcsd
  3. May 16, 2009 #2


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    Homework Helper

    Re: De Broigle's equation for "matter wave" and slowing down an object

    If you were one giant elementary particle, maybe so. But you're made up of nested structures of cells and molecules and atoms and electrons and protons and neutrons and quarks etc.etc.etc. (well I guess that's it really)... the point is, you are not an elementary particle, and that means the various components of your body will have velocities relative to each other which, under all but the most extreme circumstances, are far larger than 10^-29 m/s. Random thermal motion alone probably accounts for a few meters per second. So there's no way you could behave as a single coherent wave.

    Although if you want to try to cool yourself down to 10^-58 Kelvin to see if you turn into a wave, don't let me stop you! You might even discover something cool :biggrin: along the way. Let us know how it goes ;-)
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