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what is exactly the electron(matter) part and the positron(anti-matter) part in the electromagnetic wave? is't the oscillation or is't the E&M fields or is't something entirely else? Explanation: Pair Production

Pair production is the creation of an elementary particle and its antiparticle, for example creating an electron and positron

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    $\begingroup$ There is no "electron" or "positron" part in an electromagnetic wave, I don't understand the question. $\endgroup$
    – ACuriousMind ♦
    Commented Mar 6, 2017 at 15:11
  • $\begingroup$ @ACuriousMind watch the video $\endgroup$
    – wld.qtr
    Commented Mar 6, 2017 at 15:32
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    $\begingroup$ If the video is, indeed, telling you that three are electron and positron pats to an electromagnetic waves then it is simply wrong, but many users here are unwilling to go off site and watch a video (especially one of unspecified length) in order to first hunt down and then deal with an unspecified claim made by an unspecified source. $\endgroup$
    – dmckee --- ex-moderator kitten
    Commented Mar 6, 2017 at 16:48

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The video is not clear on what is happening. A single photon travelling in vacuum can never create a real electron positron pair, because of inconsistency in the rest frames of before and after. Before there is only the photon which has no rest frame and 0 invariant mass. After there is an electron positron pair whose added fourvectors will have at least 2*m_electron invariant mass.

This is what is happening as far as quantum mechanical solutions go for creation by an incoming impinging photon an electron positron pair.:

enter image description here

The incoming real photon exchanges a virtual electron which interacts with a virtual photon with the electric field of the nucleus, andthe incoming energy is converted to the outgoing pair of a real electron and a real positron. Thus energy and momentum balances are kept.

what is exactly the electron(matter) part and the positron(anti-matter) part in the electromagnetic wave? is't the oscillation or is't the E&M fields or is't something entirely else?

There does exist the phenomenon of virtual electron positron feynman loops as the photon goes along in vacuum, but they are a mathematical construct that allows calculations of finer structure than the first order calculations ( the above diagram) give. And that is another story that needs quantum electrodynamics to understand the mathematics.

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  • $\begingroup$ According to this other video the matter & anti-matter are actually appearing and disappearing all the time and when a photon with the right condition interact with them they scatter and don't disappear as they usually do. So I guess light has nothing to do with the creation of matter & anti-mater but space are. $\endgroup$
    – wld.qtr
    Commented Mar 6, 2017 at 16:38
  • $\begingroup$ They are not appearing and disappearing as real particles, only virtual ones . i.e. mathematical constructs. They cannot be real because of the energy momentum rules. The" right conditions" mean a field with which the photon can interact in order to keep the energy momentum balances. imposed by special relativity. The video at best is misleading. It is not only the heisenberg uncertainty that constrains , but also momentum and energy conservation as I have explained. The particles can become real only if fed by an external field which will conserve momentum. $\endgroup$
    – anna v
    Commented Mar 6, 2017 at 17:07
  • $\begingroup$ As the expectation value energy of the vacuum is zero, it has no meaning to say space is populated. Space can be populated if there are sources of fields , as the nucleus above. $\endgroup$
    – anna v
    Commented Mar 6, 2017 at 17:12
  • $\begingroup$ Yes, momentum and energy conservation were mentioned in the video and this what i meant by the right conditions (right energy level & external field) but I was interested in the particles them self and from where they originate, turns out from space. $\endgroup$
    – wld.qtr
    Commented Mar 6, 2017 at 17:25

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