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Title: GR9677.096
Post by: conantee on December 08, 2010, 04:40:20 AM
96. Which of the following reasons explains why a photon cannot decay to an electron and a positron (\gamma \to e^+ + e^-) in free space?
(A) Linear momentum and energy are not both conserved.
(B) Linear momentum and angular momentum are not both conserved.
(C) Angular momentum and parity are not both conserved.
(D) Parity and strangeness are not both conserved.
(E) Charge and lepton number are not both conserved.