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Positron - hole theory

  1. May 1, 2005 #1
    In sense of the Dirac hole theory the space must have a charge that is infiniti positive. Why do then electric neutral atoms exist?
  2. jcsd
  3. May 1, 2005 #2


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    Where did u get that conclusion...?:bugeye:

  4. May 1, 2005 #3
    There is an equation E^2=m^2p^2+m^2c^4 and of course it has negative energy solutions. So an electron could emit photons until it is in a infinite negative energy state. To prevent that Dirac said that all negative energy states in an atom are filled (Pauli exclusion principle). And if there are all states field there must be an infiniti charge. You see?
  5. May 1, 2005 #4


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    What are positrons doing in electronic atoms...?

  6. May 10, 2005 #5
    But the Dirac theory has been out of date, replaced by QFT. In QFT, the space is not full of positron, and your question is solved.

    But I think even using Dirac's theory, the problem can also be sattled. Because if the space is full filled with positron, the force related with the positron are canceled because of the uniformity of spacetime. As the
    EM force is linear, the force we feel is the departure, that is, force produced by electrons or holes. So we call them charge, instead of calling the real charge in space "charge". This is only a matter of definition.

    I hope this would be helpful.

  7. May 11, 2005 #6
    That is incorrect. Dirac theory is essential in QM and relativistic QM. QFT is the unification of both QM and special relativity so the things you say can't be true by simple definition.

    I also don't understand what the original poster is talking about. Please, elaborate on your conceptual problem

  8. May 11, 2005 #7
    I have solved my problems. Sorry that the post was so weird.
  9. May 11, 2005 #8
    I only say the Dirac hole theory, not the hole Dirac theory, sorry for not saying clearly.

    In my opinion, the Dirac hole theory is not very useful in non-relativistic QM because no nagative energy accured from the Pauli equation. In relativistic QM, the Dirac hole theory may slove some difficulties, to say, the nagative energy of the 1/2 spin particle. But the method can not pass through to spin 0 and spin 1 particles. The charged scalar particle's negative energy and anti-particle can not be worked out in the same way, but they accually exists as \pi^{\pm}. The same reason for W^{\pm}, H^{\pm}, etc. so the relativistic QM contains inconsistency inside itself. And the modern experiments are not relativistic QM flavored, but support QED.

    thank you for pointing out my weakpoint, and eager to discuss:)
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