antimatter

Matter and antimatter particles can behave differently, but where these differences show up is still a puzzle. Scientists on the LHCb experiment at the Large Hadron Collider study much more subtle differences between matter particles and their antimatter equivalents. A recent analysis allowed them to revisit an old mystery — an asymmetry between asymmetries.

Handedness — and the related concept of chirality — are double-sided ways of understanding how matter breaks symmetries. Different-handed object pairs reveal some puzzling asymmetries in the way our universe works.

Einstein’s equation E = mc2and the theory of the Big Bang are both generally accepted physics theories, and yet, between them, they make an unphysical prediction. They predict that matter and antimatter should be observed in equal quantities. Yet the universe is made only of matter. Why is that? In this 11-minute episode of Subatomic Stories, Fermilab scientist Don Lincoln explains what is going on.

From Physics Today, June 1, 2020: Somewhere in the laws of physics, particles must be allowed to behave differently from their antiparticles. If they weren’t, the universe would contain equal amounts of matter and antimatter, all the particles and antiparticles would promptly annihilate one another, and none of us would exist. Fermilab’s NOvA neutrino experiment and the international Deep Underground Neutrino Experiment, hosted by Fermilab, are pinning down CP violation, the property that could explain the imbalance.

From Gizmodo, May 18, 2020: Neutrino physics is a trek into the unknown, one that the United States physics community has chosen to pursue full-on. A flagship experiment called LBNF/DUNE will lead the search, in pursuit of answers that may take decades or more to find. Fermilab Deputy Director for Research Joe Lykken, DUNE spokesperson Ed Blucher, and DUNE scientists Chang Kee Jung and Elizabeth Worcester talk about how neutrinos will enhance our understanding of the universe.

One of the amazing claims in physics is that for every kind of known matter, there is a cousin version called antimatter. Antimatter is the opposite of ordinary matter and will annihilate into pure energy when it encounters matter. In episode 7 of Subatomic Stories, Fermilab scientist Don Lincoln gives you the low-down on this amazing substance.

From Sanford Underground Research Facility, May 12, 2020: Part I in Sanford Lab’s series exploring the science goals of the international Deep Underground Neutrino Experiment discusses antimatter, CP violation and the origins of the universe.

From Quanta Magazine, April 15, 2020: The first official evidence of a key imbalance between neutrinos and antineutrinos provides one of the best clues for why the universe contains something rather than nothing. Fermilab scientist Debbie Harris comments on the T2K experiment’s latest result. Fermilab’s NOvA experiment and the international Deep Underground Neutrino Experiment, hosted by Fermilab, will also help provide a more precise understanding of the asymmetry.