Stars, galaxies, and everything in the universe, including our own bodies, are comprised of so-called regular matter. Regular matter includes atoms and molecules, which are made up of tiny particles, such as electrons, protons, and neutrons.
These particles dominate our universe, vastly outnumbering their lesser-known counterparts: antimatter particles. First experimentally discovered in 1932 by the late Nobel laureate and longtime Caltech professor Carl Anderson (BS ’27, PhD ’30), antimatter particles have the opposite charges to their matter counterparts. The antimatter particle to the negatively charged electron, for example, is the positively charged positron.
How did matter come to overshadow antimatter? Scientists believe that something happened early in the history of our cosmos to tip the balance of particles to matter, causing antimatter to largely disappear. How this occurred is still a mystery.
In a new study in the journal Physical Review Letters, Nick Hutzler (BS ’07), assistant professor of physics at Caltech, and his graduate student Phelan Yu, propose a new tabletop-based tool to search for answers to the antimatter riddle. Like other physicists studying the problem, the researchers’ main idea is to look for asymmetries in how regular matter interacts with electromagnetic fields. This is related to a type of symmetry commonly seen in particles called charge parity, or CP. Any deviations from the expected CP symmetry might explain how matter ultimately edged out antimatter in our universe.
Source: “Radioactive Molecules May Help Solve Mystery of Missing Antimatter”, Whitney Clavin, California Institute of Technology