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Among the problems yet to be solved by particle theory, we consider those that are most important in our opinion, some of which require physics beyond the Standard Model (neutrino oscillations, probably inconsistent with the usual three-generation scheme; astrophysical evidence for new physics; electroweak symmetry breaking, and the hierarchy of parameters) and some of which do not (description of strong interactions at low and intermediate energies).
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S. Troitsky (2012) studied this question.
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