This is an open question, and an important one to understanding the early history of the universe. Essentially, as far as everything we have seen in the lab sho

This is an open question, and an important one to understanding the early history of the universe. Essentially, as far as everything we have seen in the lab shows, and everything we know about the laws of physics says, certain quantities like charge must be conserved, so matter and antimatter are always generated together. However, this creates a glaring issue- where the Hell is all the antimatter? The universe is, as far as we know, made almost entirely of matter with very little antimatter, and so there must be some kind of asymmetry somewhere that we haven't found yet. Otherwise the universe would be 50/50 matter/antimatter, or would just be constantly forming and destroying matter and antimatter.