Main Question or Discussion Point
Why do antimatter and matter annihilate when they collide?
Generally speaking, many physicists do not answer questions starting by "Why"...
LOL. Not being a physicist myself I can respond to that. (Though you probably weren't entirely serious, I kind of feel as though this might be the place for a “Why did the physicist cross the road?” joke.)Why not?
Actually, it is a consequence opf marrying quantum mechanics with special relativity. When you do that (or, when dirac did that I should say) you have no choice than to introduce the concept of antiparticles. It is forced upon you by the formalism. And then, once you couple the electron (and its antiparticle) to an electromagnetic field, you have no choice than to accept that an electron and a positron will annihilate into photons. When you couple them to the weak gauge bosons, you find that they will also annihilate into Z bosons.Why do antimatter and matter annihilate when they collide?