Two questions(adsbygoogle = window.adsbygoogle || []).push({});

Both of these occur in a vacuum:

If a photon has the exact energy to electron-positron pair product, since the electron and the positron are the same mass, if stationary would have an energy of Mc^2. Since they are moving would there energy be (of one fermion):

E=(mc^2)+(1/2mv^2)

or

E=mc

If that is true does that mean the energy of the photon (in a vacuum) would be:

Ey=2((mc^2)+(1/2mv^2)

or

Ey=2(mc^2)

Then, in a vacuum, would the electron and the positron collide? The second question is the previous one and what is velocity needed for anihilation?

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# Electron velocity

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