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Homework Help: Fermi Question - quantum tunnelling of a person

  1. Jul 23, 2007 #1
    1. The problem statement, all variables and given/known data

    The probability of a person quantum mechanically tunnelling through a wall

    2. Relevant equations

    3. The attempt at a solution

    I'm not too sure how to approach this problem, I calculated the de Broglie wavelength of the person (mass = 60kg, velocity = 30 m/s; These values are made up by me). But then I get stuck, what can I infer from the wavelength that is calculated. I looked at the barrier potential problem, and I'm not sure how to construct a wavefunction for the person (if it is even possible? I thought of using the plane wave solution and calculating the momentum and wavenumber that appears in the complex exponential term), also the wall would represent the barrier potential (would this potential tend to infinity? like the infinite square well problem?)

    My brain is melting...
  2. jcsd
  3. Jul 23, 2007 #2
    I guess that you have to estimate the probability for EACH single atom to tunnel through the potential barrier and then multiply all the probabilities together and get something like almost 0. However, I don't know how to calculate the energy for each atom and how many atoms our body has.
  4. Jul 23, 2007 #3


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    Sounds reasonably straightforward to use a plane wave type tunneling problem as a model. But I have no clue how you are supposed to estimate the height of the potential barrier. If it's infinity, there is no tunneling.
  5. Jul 25, 2007 #4
    I know this is cheating but I found the answer here http://physuna.phs.uc.edu/suranyi/Modern_physics/Lecture_Notes/modern_physics6.html [Broken]
    Last edited by a moderator: May 3, 2017
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