Prove that a photon in a vacuum, no matter how high its energy is, cannot transform to an electron-positron pair.

Prove that a photon in a vacuum, no matter how high its energy is, can

1.	Prove that a photon in a vacuum, no matter how high its energy is, cannot transform to an electron-positron pair.
Answer» Solution :Suppose that the photon PRODUCES a pair of PARTICLES with identical momenta. In this CASE the laws of conservation of energy and the momentum will be writen in the form `epsi_(ph)=2mc^(2),epsi_(ph//c)=2mvcosalpha` Hence `2mc^(2)=2mvc COSALPHA,orc=vcosalpha`, which is impossible.

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Prove that a photon in a vacuum, no matter how high its energy is, cannot transform to an electron-positron pair.

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