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Electron-positron pair production

  1. Jun 14, 2015 #1
    Is it true that static electric field 10^16 V/cm2 is capable to create positron-electron pairs? Is this process associated with energy release? If yes, where energy comes from?
     
  2. jcsd
  3. Jun 15, 2015 #2

    Simon Bridge

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    You can get pair production from a static electric field.
    The process is not associated with any additional energy release.

    i.e.
    http://arxiv.org/abs/1112.4120
     
  4. Jun 15, 2015 #3

    ChrisVer

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    How can one produce a Sauter electric field/potential? The potential looks like a step-function one.
     
  5. Jun 15, 2015 #4
    But if you need no energy to maintain electrostatic field, in principle, and this field creates positrons and electrons from ''nothingless'' and these positrons have real energy and could annihilate with something releasing gamma rays, wouldn't it mean we received energy from physical vacuum?
     
  6. Jun 15, 2015 #5

    mfb

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    For fields so strong that you get pair production you do need energy to maintain them. Otherwise the produced charges will weaken it over time (as electrons go to the positive side and positrons go to the negative side).
    It is just a conversion of energy - from strong electric fields to particle masses and weaker fields.
     
  7. Jun 15, 2015 #6

    Simon Bridge

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    ... the field does not make positrons and electrons out of "nothingness" nor out of "physical vacuum". As you point out, if it did, then energy would not be conserved.

    The energy to make the particle/anti-particle pair comes from the electric field.
    Please see: http://ryuc.info/creativityphysics/energy/pair_production.htm
     
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