By Ares Astro
On January 4th, 1996, CERN managed to produce the first atoms of antimatter ever created in a lab. This spawned into a now 20 year strong field of research resulting in some incredible science. You see, much of our understanding of the early Universe rests upon complex physical models which attempt to coherently explain the phenomena that we believe led to our existence. It is very rare that we have a chance to test these phenomena in a lab, and doing so often requires nothing short of some of the greatest minds on Earth coming together to design experiments around proving or falsifying them. One of these phenomena is that of matter and antimatter, and we hope that by studying it, we may come to know more about how our universe came into being.
Our models predict that in it’s infancy, the Universe consisted of many pairs of matter and antimatter. Most of these pairs instantly annihilated one another due to their opposing charges, however for reasons unknown, there was a slight imbalance. This led to the existence of more matter than antimatter in our Universe. This is commonly referred to as the baryon asymmetry problem, and by understanding it, we will in turn gain a better understanding of how the Universe works.
One of the predictions of antimatter theory was that antimatter atoms should display the same behaviours and properties as their matter-based counterparts. This is because they are essentially a mirror image of one another. For example, where a hydrogen atom consists of an electron and a proton, an antihydrogen atom consists of a positron and an antiproton. One of the ways to test this hypothesis is to observe the visible spectrum of an antimatter atom and compare it to it’s counterpart as it transitions between different levels of excitation when exposed to a laser.
“Using a laser to observe a transition in antihydrogen and comparing it to hydrogen to see if they obey the same laws of physics has always been a key goal of antimatter research,” – Jeffrey Hangst, Spokesperson of the ALPHA collaboration.
This prediction has been quite difficult to test as trapping antimatter at all is exceedingly difficult, let alone trapping enough antimatter atoms to be able to observe spectral data. In previous trials, they were only able to trap an average of 1.2 antihydrogen atoms. Astonishingly, with their new method of collaborative anti-atom stacking, the team at the ALPHA collaboration at CERN were able to produce 14 whole atoms of antihydrogen in their most recent trial. This has finally enabled them to their hypothesis, and the results are in: Our physical models are correct! Needless to say, we’re incredibly excited to see where this new breakthrough leads in expanding our knowledge and understanding of the Universe and our place in it.
For more information about the experiment, check out this video from the ALPHA collaboration at CERN.