Tantalising peeks at a particle recluse

摘要

Sterile neutrinos, hypothetical particles so aloof they may flit off into other dimensions at the drop of a hat, may finally be stepping into view. If their existence is confirmed, they might account for dark matter and could point the way to other exotic particles that do not fit into the standard model of physics. The model is physicists' best idea of how particles interact with three of the four fundamental forces - electromagnetism and the strong and weak nuclear forces. "So far we have no compelling measurement of a particle that doesn't participate in the standard model interactions," says Tom Weiler of Vanderbilt University in Nashville, Tennessee.