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Have all the electrons in this universe come from a single electron?

  1. Jun 11, 2007 #1

    Suppose we have a problem that, in a given 3D space, we had isolated a single electron. But after 5 minutes, there are a 100 electrons there. The physicists are confused where these extra electrons came from?

    Feynman said that an electron can absorb a photon and convert to a positron, which travels back in time.
    The above problem happened as follows: we had a single electron at 0600 hrs. At 0601 hrs, it collided with a photon, converted into a positron and travelled back in time. It reached 0600 hrs, released a photon and converted back into an electron inside the same 3D space. This electron again converted to a photon and came back as an electron at 0605 hrs. In such a way a large number of electrons are formed, out of which 100 electrons were
    present at 0605 hrs, when the physicists made the observation.

    I know this must be extremely weird, but is there a probability for this to happen? If yes, isn't there a possibility that a large number of electrons are actually made out of a single electron? Maybe all the electrons in the whole universe are actually formed from a single electron.

    Just tell me if it is probable at all.

    Thanks so much

    Mr V
  2. jcsd
  3. Jun 11, 2007 #2
    anything is possible I guess.
  4. Jun 11, 2007 #3
    It seems that you are talking about virtual electrons, those with an energy less than Planck's constant over the time measured. There can exist such an effect by a near-infinity of virtual particles, as long as they obey this relation.

    Electrons are only distinguishable with respect to the state they're in. An observer can measure only one real electron, with its unique set of quantum numbers, at a time.

    The overall effect of many electrons considers an aggregate "wavefunction" ("probability density"), which in general is not the same as the sum of individual electron wavefunctions. I. e., in quantum mechanics the total wavefunction is most often not equal to the summed wavefunctions of its parts.
  5. Jun 11, 2007 #4
    Thanks for the web site. its interesting ^
  6. Jun 12, 2007 #5
    Actually, there's definitely no chance of it happening the way you've described. If an electron travels back in time after an interaction with a photon, it's the same as a positron traveling forward in time; so we would be able to to observe a positron at the past time in the first place. Interaction with a photon can not allow an electron to signal its own past, or change it's past time line.

    Feynman was just pointing out that a positron traveling forward in time is indistinguishable from an electron traveling the other direction; this doesn't allow signaling to the past, it just demonstrates the reversibility of time on the small scale. But on a large enough scale, entropy indicates a definite direction of time, anyway.
  7. Jun 12, 2007 #6
    What I really meant to ask was: is there any chance of an electron to be present at two places at the same time, by any type of interaction with its surroundings.

    Mr V
  8. Jun 13, 2007 #7


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    You need verifiable references here and something more concrete than what you have so far to continue. If not, this is considered to be nothing more than speculative personal theory, and that is covered clearly in our PF Guidelines.

    I know you are asking a question here, but you really need some justifiable impetus for such a speculative question.

  9. Jun 13, 2007 #8
    Dear ZapperZ
    I actually once listened to Feynman's lectures, where he mentioned that a positron is actually an electron going backwards in time. He did not actually give any mathematical explanation for this in his lectures. However, he did draw some diagrams in which repetitive electron-positron conversions along with time travel were taking place (and he assured the audience that they had carried out those experiments in labs). That is why I thought if this idea. It is only an idea. And since QED is not my field, I do not have any concrete mathematical explanation for it.

    Mr Virtual
  10. Jun 13, 2007 #9


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    But even you must admit that it is A HUGE JUMP from Feyman's diagram description of electrons going back in time to all electrons in the universe come from a single electron!

    Furthermore, and this has been mentioned already, an electron going back in time is identical to a positron going forward in time. If what you described in the OP is true, then in creating all those photoelectrons in a photoelectric effect, I would also be detecting the identical number of positrons! Where are they? And when I put a conductor in a magnetic field and do something similar to a Hall effect, how come I get no measurable effect due to these co-existing positrons?

    You have no offered plausible mechanism to explain what we have observed.

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