antimatter

From Reccom Magazine, Feb. 26, 2021: Chuck Brown of the Fermilab SeaQuest research team is quoted in this piece on the sea of quarks inside the proton. The article discusses Fermilab’s contributions to the SeaQuest and NuSea experiments.

Protons are built from three quarks — two “up” quarks and one “down” quark. But they also contain a roiling sea of transient quarks and antiquarks that fluctuate into existence before swiftly annihilating one another. At the Fermilab-hosted SeaQuest experiment, researchers report that that lopsidedness persists in a realm of previously unexplored quark momenta.

From Forbes, Feb. 10, 2021: Fermilab scientist Don Lincoln explains why there should be equal amounts of matter and antimatter in the universe. There aren’t. He discusses several current theories that try to explain the discrepancy. Better understanding this imbalance is an aim of ongoing experiments, such as DUNE, which is being built at Fermilab.

From New Scientist, Jan. 25, 2021: The Big Bang left us the universe — and a major set of mysteries around antimatter, dark matter, dark energy, and cosmic inflation. While the Large Hadron Collider looks at what the laws of physics were like a trillionth of a second after the Big Bang, Dan Hooper, head of theoretical astrophysics at Fermilab, thinks the answers to these puzzles may depend on better understanding that first fraction of a second — even closer to the universe’s beginning.

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.

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.