Answer to Question #121957 in Astronomy | Astrophysics for Christina Nguyen

Question

Explain why the process of particle-antiparticle pair annihilation stopped happening, and the significance of it stopping to the formation of the Universe

Answer 1

After the Big Bang, the universe should have produced an equal number of particles and antiparticles. Of course, they should have annihilated and the universe that we see now would be just energy. For some reason, the mechanisms responsible for the existence of particles and antiparticles cannot be equally applied both for particles and antiparticles. The equilibrium is shifted to the particles’ side. Scientists still try to figure out what could lead to this disbalance. But there is a good consequence: since not all particles annihilated, the universe could form. And the major part of the universe we see now is made of particles.