Sterile Neutrinos

A hypothetical, "sterile" counterpart to the three known "active" neutrinos. They are so named because they would not interact via the weak force - the only known force that affects regular neutrinos. A sterile neutrino would feel only gravity, making it an immediate and compelling candidate for dark matter. Its existence is hinted at by several anomalous experimental results that suggest neutrinos might be oscillating into this hidden, sterile state. If it exists, it would be a monumental discovery, providing a single, elegant solution to two puzzles: the anomalous behavior of neutrinos and the identity of the invisible matter that holds the universe together.