Physicists have created antimatter in the laboratory. But when they do, they create an equal amount of matter. That suggests that the Big Bang must have created matter and antimatter in equal quantities. Yet almost everything we see around us, from the ground beneath our feet to the most remote galaxies, is made of ordinary matter.
1 Answer
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This is a very well-known problem in physics, and the short answer is we don't know. Conditions for baryogenesis have been proposed, and there is some physical mechanism for producing more matter than antimatter (see CP violation), but not in sufficient quantities to explain the current dominance of matter over antimatter.
Whoever figures out the answer to this question is virtually certain to win a Nobel Prize.
