How the Tiniest Particles in the Cosmos Saved Us All from Annihilation

Matter and anti-matter completely annihilate when they meet, erupting into pure energy. If the Universe began with equal amounts of each, why does anything still exist? The answer may lie with the smallest particle of all.

Ripples in spacetime known as gravitational waves could reveal the answer to one of the greatest questions in the study of the Cosmos — why anti-matter in the early Universe did not completely annihilate every particle of matter and vice versa.

According to widely-accepted models of the Big Bang, the enormous energy of the explosion soon began to freeze into subatomic particles. As the Universe continued to expand and cool, matter and anti-matter formed (theoretically) in equal amounts. Were that the whole story, however, these particles should have eventually wiped each other out of existence.

Anti-matter is seen on the surface of the Sun, as it collides with matter, annihilating both partners in subatomic collisions. So, why is matter so prevalent in the Universe, and anti-matter so rare? Image credit: NASA

But, when we look around us, everything we observe — from the tiniest microbe to the largest galaxy, is made of matter, while the presence of anti-matter seems to be relegated to high-energy environments like the surface of stars or the merger of black holes.

It’s Just a Phase…

One way to explain why matter seems omnipresent today is that early in the age of the Cosmos, a tiny amount of the anti-matter of the…