Physicists investigate why matter and antimatter are not mirror images

AS MISMATCHES go, it's a big one. When physicists bring the Standard Model of particle physics and Einstein's general theory of relativity together they get a clear prediction. In the very early universe, equal amounts of matter and antimatter should have come into being. Since the one famously annihilates the other, the result should be a universe full of radiation, but without the stars, planets and nebulae that make up galaxies. Yet stars, planets and nebulae do exist. The inference is that m...