Based only on the latest measurement of the antiproton magnetic moment, the universe shouldn’t exist. The value shows that protons and their antiparticles are equal in everything but charge and they should have annihilated themselves in the first few instants after the Big Bang.
Obviously, there is a lot more to antimatter physics than just antiprotons, but this result tells us that the answer to why matter dominates in the universe won’t be discovered here. The finding, published in Nature, is 350 times more precise than the previous one. This is the first time that the uncertainty of antiproton measurement is smaller than it is for protons.
“It is probably the first time that physicists get a more precise measurement for antimatter than for matter, which demonstrates the extraordinary progress accomplished at CERN’s Antiproton Decelerator,” first-author of the study Christian Smorra, from CERN, said in a statement.
To perform the measurement, the researchers had to store antiprotons in a Penning trap, a special device that uses magnetic and electric fields to keep charged particles from encountering matter and annihilating themselves. You wouldn’t be able to store antimatter in a regular container.
“This result is the culmination of many years of continuous research and development, and the successful completion of one of the most difficult measurements ever performed in a Penning trap instrument,” Stefan Ulmer, a spokesperson for the BASE collaboration, added.
The BASE collaboration was also the team that found the most accurate value for the proton magnetic moment in 2014. If we were to base our interpretation of the universe on these measurements alone, we would have to conclude that our universe couldn’t exist. Matter and antimatter are exactly the same, perfectly symmetric, and neither should have dominated at the dawn of time.
Obviously, the universe seems to care very little about our current ignorance, as well as how it exists, it has even hidden what causes this asymmetry. How antiprotons respond to a magnetic field is one of the many avenues that physicists around the world have been investigating to answer this mystery. Neutrino detectors across the world and even the LHCb experiment at CERN are all looking at potential sources of this asymmetry. Matter clearly has something going on. We just have to find it.