A substance called antimatter is at the heart of one of the greatest mysteries of the universe. We know that every particle has an antimatter companion that is virtually identical to itself, but with the opposite charge. When a particle and its antiparticle meet, they annihilate each other—disappearing in a burst of light.
A substance called antimatter is at the heart of one of the greatest mysteries of the universe. We know that every particle has an antimatter companion that is virtually identical to itself, but with the opposite charge. When a particle and its antiparticle meet, they annihilate each other—disappearing in a burst of light.
Our current understanding of physics predicts that equal quantities of matter and antimatter should have been created during the formation of the universe. But this doesn’t seem to have happened as it would have resulted in all particles annihilating right away.
Instead, there’s plenty of matter around us, yet very little antimatter—even deep in space. This enigma has led to a grand search to to find flaws in the theory or otherwise explain the missing antimatter.
One such approach has focused on gravity. Perhaps antimatter behaves differently under gravity, being pulled in the opposite direction to matter? If so, we might simply be in a part of the universe from which it is impossible to observe the antimatter.
Our new study, published in Nature, reveals how antimatter actually behaves under the influence of gravity.
Other approaches to the question of why we observe more matter than antimatter span numerous sub-fields in physics. These range from astrophysics—aiming to observe and predict the behavior of antimatter in the cosmos with experiments—to high energy particle physics, investigating the processes and fundamental particles that form antimatter and govern their lifetime.
While slight differences have been observed in the lifetime of some antimatter particles compared to their matter counterparts, these results are still far from a sufficient explanation of the asymmetry.
