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The proton is not decaying as fast as the simplest unified field theory—SU(5)—predicts. But this is no cause for despair: the search should be for something even simpler.
IN a recent issue of Nature, Jean Wang discussed the differences between the cellular and viral versions of the abl oncogene1. This week John Wyke reports some recent explorations of two versions of v-src and its cellular homologue.
