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Increase in amplitude of an electron wave

  1. Feb 18, 2012 #1
    Like photons, all particles have a wave/particle duality, so when energy is added to an electron, say in a particle accelerator, why does the "amplitude" of the electron wave never increase (say as an increase in the actual number of electrons) - why is it that the energy added always just comes out in the form of a reduction in wavelength of the single electron, keeping the number of electrons at "1"? It seems to be the same with photons - whenever energy is added it's just the frequency that changes, never the amplitude/intensity, as would happen with a wave? For example - if we added energy to a water wave, it would get physically bigger - it's amplitude would increase.
  2. jcsd
  3. Feb 18, 2012 #2


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    For photons it is more complicated, depending on how the energy is added. For example, in a laser the frequency stays the same, but the amplitude is increased.
  4. Feb 18, 2012 #3
    The wavefunction of a particle must satisfy the following condition:
    \int_{-\infty}^{\infty} |\Psi|^2 dx = 1
    Basically, this means that the total probability of finding the particle anywhere is one. It doesn't really make sense otherwise.

    If you were to increase the amplitude of the wave by 2 everywhere, for example, the integral would be equal to 4. That essentially means there are now 4 particles.
  5. Feb 18, 2012 #4
    The amplitude is of probabilities (of locating photon) not frequency/energy. This "wave" is just a mathematical tool not any actual wave.

    The probabilities as Browne suggests must equal one. However it does not have to be four particles, just one particle
    with probabilities re-normalized.
  6. Feb 18, 2012 #5
    What does "probabilities normalized" mean?
  7. Feb 18, 2012 #6
    the summation/integral brought back to one...

    a sum above 1 would mean the same particle showing up at two places at the same time.....
    Last edited: Feb 18, 2012
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