Belgian-American scientist Francis Halzen won the Nobel Prize in Physics Oct. 6 for his research on a rare group of cosmic neutrinos, tiny electrically neutral particles that are often referred to as “ghost particles” and could reveal the evolutionary story of the universe.
Neutrinos are hard to track due to their small size, and travel everywhere, all at once, leaving stars like the sun in trillions and entering our bodies every second, according to The Associated Press News.
“[Neutrinos] are coming from various parts of our own galaxy, and they are coming also from other galaxies because of lots of nuclear events that are happening, and neutrinos are being produced,” Itzhak Bars, a USC physics and astronomy professor, said.
Halzen used Antarctic ice to track neutrinos’ behavior by monitoring when the particles collided with ice. His research contributed to the creation of the IceCube Neutrino Observatory in Antarctica, which captured the first high-energy neutrinos from faraway galaxies, according to the AP.
“Coming from other galaxies that are very far away from us, those neutrinos have very high energies, and it was expected that these neutrinos do exist, but nobody really had seen them, nobody had detected them, but this facility called the IceCube managed to detect this,” Bars said.
Bars explained that using the IceCube, “neutrinos can tell you much more precisely exactly from which direction they are coming from.” While telescopes track light, light often interacts with multiple sources before reaching researchers, according to NASA, but neutrinos can arrive at Earth without significantly interacting with another source.
These neutrino studies could reveal clues about the creation of other galaxies and even the universe, according to the AP. Halzen’s work made neutrino astronomy possible, and with the now 400 scientists representing 14 countries at the IceCube Neutrino Observatory, the possibilities are endless.
Some at USC believe that Halzen’s discoveries pushed research in the evolution of the universe to a different level.
“Photons change energy as they go up in the atmosphere, but it will take a million years for that neutrino’s energy to emerge from the surface, but on the other hand, the neutrino must travel at the speed of light, so they just slip right through,” said Geraldine Peters, a USC physics and astronomy professor. “So by observing the neutrino flux from the sun at this point in time, we’re getting an idea of what is really happening inside the center of the sun.”
At USC, Bars said that the physics department engages with theoretical research relating to neutrinos and space physics. Bars specifically works with the High Energy Physics Group, which focuses on high-energy physics relating to quantum mechanics and black holes.
Edited by Ally Nakamura and Leo Li