As I understand it, the dynamical Casimir effect has been demonstrated in the laboratory and has been found to allow the emission of photons from the vacuum. Given the right frequency of the oscillating mirror, and the right energy supplied to the experiment, could one potentially produce fermions such as a proton or neutron? Do protons/positrons get created as virtual particle pairs in the zero point energy fluctuations, or only bosons?


It is confusing to think of vacuum as "no energy there". When real photons are produced, i.e with a four vector that can be measured in the lab, this means the energy has been supplied . This means that the mathematically assumed vacuum in the model for the experiment has an energy density that can produce the photons.

If the energy density of the vacuum is enough for the production of a pair of fermions there is no reason why this cannot happen. A pair of fermions has to be produced because of quantum number conservation laws: a vacuum may have energy in the mathematical formulation, but no quantum numbers.

As one needs 0.551MeV for each, electron and positron, this cannot happen in the Casimir experiment. The vacuum energy density is supplied by the solid state electromagnetic energies which are of much smaller energy, as the experiment found microwave radiation ( order ~$10^{-5}$ electron volts).

  • $\begingroup$ I'm unfortunately a beginner on the subject. Does the vacuum have differing energy densities? I would assume that the vacuum is pretty uniform outside of a field interaction...? $\endgroup$ Feb 3 '20 at 5:16
  • $\begingroup$ You would need a field theory course. see if my summary on field theory here physics.stackexchange.com/questions/515923/… . and here physics.stackexchange.com/questions/461821/… $\endgroup$
    – anna v
    Feb 3 '20 at 5:45
  • $\begingroup$ I'm curious to know if the standard model would allow the creation of fermions. $\endgroup$ Feb 19 '20 at 20:39
  • $\begingroup$ The problem is conservation of energy, which is a law higher than the standard model. The SM allows pair protduction , particle antiparticle, of fermions, but the energy has to be supplied . In the Cassimir effect there is not enough energy in the vacuum generated by the Casimir effect. $\endgroup$
    – anna v
    Feb 20 '20 at 4:01
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    $\begingroup$ In general, if energy is supplied yes, as with pair creation by photons in the nuclear field. There are no materials that can supply such an energy.as I say in my last paragraph. $\endgroup$
    – anna v
    Feb 22 '20 at 5:38

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