Northwestern University Physicists Trap Antimatter for Months

Physicists at Northwestern University have managed to keep an antimatter particle under control for months. Published in the journal Physical Review Letters, the study captured a positron, the antiparticle of the electron; the researchers first slowed down the high-speed particle emerging from radioactive sodium and then dropped its temperature down to minus 273 degrees.

Antimatter encountering normal matter enters into a reaction that causes the two particles to annihilate each other. Therefore, to capture the positron, the researchers developed a special device called a single-positron quantum cyclotron, which can precisely alter the energy levels of the particle. Moreover, doing this without destroying the positron paved the way for repeatedly examining the behavior of the particle for months.

The team's main goal is to compare the magnetic properties of the positron and the electron. Current laws of physics state that there should be no unexpected difference between them. On the other hand, a potential discrepancy could help understand why matter remained dominant after the Big Bang. While future measurements are expected to be 30 times more precise with the new method, Gerald Gabrielse, who led the research, emphasized the significance of the potential outcome by stating, "If they turn out not to be equal, it would be the biggest physics discovery of the past hundred years."