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Positronium from vacuum fluctuations ?

  1. Apr 22, 2014 #1

    I wondered if it is theoretically possible that the vacuum energy produces an electron/positron pair which then bonds into positronium instead of directly annihilating again. And if it is theoretically possible has this ever been observed ?

    Thanks and cheers.
  2. jcsd
  3. Apr 22, 2014 #2
    No. This would violate energy conservation.
  4. Apr 23, 2014 #3
    I see. So how could I visualize this ? The electron/positron pair which can be spontanously produced by vacuum fluctuations (which should be possible, causing the casimir effect) do not separate far enough to escape each other (to produce a "real" electron/positron pair) nor to separate enough to create a positronium system ? Is that right ?
  5. Apr 23, 2014 #4
    It's a really new paper.


    Submitted on 21 Apr 2014


    Positron scattering and annihilation on noble gas atoms below the positronium formation threshold is studied ab initio using many-body theory methods. The many-body theory provides a near-complete understanding of the positron-noble-gas-atom system at these energies and yields accurate numerical results. It accounts for positron-atom and electron-positron correlations, e.g., polarization of the atom by the incident positron and the non-perturbative process of virtual positronium formation. These correlations have a large effect on the scattering dynamics and result in a strong enhancement of the annihilation rates compared to the independent-particle mean-field description. Computed elastic scattering cross sections are found to be in good agreement with recent experimental results and Kohn variational and convergent close-coupling calculations. The calculated values of the annihilation rate parameter Zeff (effective number of electrons participating in annihilation) rise steeply along the sequence of noble gas atoms due to the increasing strength of the correlation effects, and agree well with experimental data.
    Last edited: Apr 23, 2014
  6. Apr 28, 2014 #5
    ah thank you. so if i understand it correctly this article seems to suggest that spontaneous creation of virtual positronium is indeed a possibility.
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