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De broglie and electron transitions

  1. Aug 29, 2004 #1
    Is it possible that electron transitions from a high energy state to a low energy state are caused by the electrons interacting with some other partilces in the space around atoms.Let's look at the case of a hydrogen atom:
    According to Niels Bohr, for an electron, r = n^2 h^2 / (8 pi x epsilonx me^2)
    and Energy = - E / n^2

    So in Bohr's model an electron with a greater energy (an electron that has undergone a transition) has a greater value of orbital radius.

    The de broglie wavelength of the electron is given by lambda = h/mv
    and is about 10^-11 metres.This a length we can associate with the electron.
    So if we square the de Broglie wavelength we get an area we can associate with the electron and this is 10^-22 square metres.

    Now, space is filled with dark energy, at a density of 10^-27 kg per cubic metre.If the area of our electron was facing 1m^2 of dark energy this would
    be 10^-22 x 10^-27 = 10^-49 kg of the mass of the total mass of dark energy in a cubic metre.Nobody knows what dark energy really is but let's suppose
    that like anything else in the universe that has energy it consists of particles of some sort.These particles must move close to the speed of light because dark energy is considered by experts to be more energy-like than mass-like.
    At the speed of light,10^8 m/s, 10^49 kg of dark energy particles could strike
    an area equal to the de Broglie wavelength squared in 10^-8 seconds.
    Thus is the maximum force the dark energy particles can exert on the
    area (assuming the dark energy particles are all repelled by the coulomb charge) is F = m x change of velocity/ time = 10^-49 x 10^8/10^-8
    = 10^-33 Newtons.The acceleration this would produce on an electron of mass 10^-31 kg is acceleration = Force/mass = 10^-2 m/s^2.
    A transition from n = 2 to n= 1 in the Bohr model of hydrogen amounts to a distance of about 10^-10 m.An acceleration of 10^-2 m/s^2 acting on an electron would thus move it back to the ground state in a minimum time of
    10^-8 seconds.This is what is observed.Can anyone come up with a quantum mechanical calculation that could give some more convincing evidence for dark energy causing an electronic transition from an excited to a ground state.
     
  2. jcsd
  3. Aug 29, 2004 #2
    This area you are talking about is another speculation. What is your proof for making such a statement.

    But let's suppose you are "right". I don't see how this area can be coupled to an interaction of certain particles with this electron???

    Besides a transition from excited to groundstate has very high probability so that it occurs automatically. Why trigger these events ???


    regards
    marlon
     
  4. Aug 29, 2004 #3
    Marlon:
    This area you are talking about is another speculation. What is your proof for making such a statement.

    Kurious:
    The de Broglie wavelength itself was speculation when it first came out.

    Marlon:
    Besides a transition from excited to groundstate has very high probability so that it occurs automatically. Why trigger these events ???

    kURIOUS:
    I am talking about a mechanism that can account for the time taken for the transition.

    Marlon:
    I don't see how this area can be coupled to an interaction of certain particles with this electron???


    Kurious:
    In an EM wave the electric field is spread out over the length of the wave.
    I am asking by analogy if the de Broglie wavelength says that the electric field of
    an electron can be spread out over that wavelength so that interactions with other electrically charged particles can occur in a small area given by the square of the de Broglie wavelength.
     
  5. Aug 29, 2004 #4

    Your last statement is untrue. The EM-interactions are GLOBAL. Besides the de Broglie-wavelength describes the particle in itself (not the way it can interact), not the electric field. You gotta think of these two things as some kind of dual aspects. The are different , yet they are used to describe the same thing (electron)

    regards
    marlon
     
  6. Aug 29, 2004 #5
    Not sure if this helps much, but X-ray photo-ionization cross-sections for most atoms is between 1 and 50 x 10e-28 sq-cm. Hydrogen and helium are not observed by conventional, fixed-wavelength XPS which suggests their cross-section are smaller still. The X-rays for XPS are most often Aluminum K-alpha with 8.3 ang wavelength and 1486 eV of energy.
     
  7. Aug 30, 2004 #6

    chroot

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    This is quite clearly too speculative.

    - Warren
     
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