Dark matter could be an entire dark sector of the universe, with its own particles and forces.

By Kathryn Zurek edited by Clara Moskowitz

Have you ever stood by the sea and been overwhelmed by its vastness, by how quickly it could roll in and swallow you? Evidence suggests that we are suspended in a cosmic sea of dark matter, a mysterious substance that shapes galaxies and large structures in the universe but is transparent to photons, the carriers of the electromagnetic force. Our galactic home, the Milky Way, is submerged in dark matter, but this hidden body but does not devour us, because its forces cannot touch the regular matter we’re made of.

Ultrahigh Energy Cosmic Rays are the highest-energy particles in the universe, whose energies are more than a million times what can be achieved by humans. But while the existence of UHECRs has been known for 60 years, researchers have not succeeded in formulating a satisfactory explanation for their origin that explains all the observations.

But a new theory introduced by New York University physicist Glennys Farrar provides a viable and testable explanation for how UHECRs are created.

“After six decades of effort, the origin of the mysterious highest-energy particles in the universe may finally have been identified,” says Farrar, a Collegiate Professor of Physics and Julius Silver, Rosalind S. Silver, and Enid Silver Winslow Professor at NYU. “This insight gives a new tool for understanding the most cataclysmic events of the universe: two neutron stars merging to form a black hole, which is the process responsible for the creation of many precious or exotic elements, including gold, platinum, uranium, iodine, and xenon.”