European scientists are shocked by an experiment that showed neutrino particles moving faster than light. The result, if confirmed, could challenge Einstein's signature theory on relativity or point to a universe of more than four dimensions.
Scientists at the European Organization for Nuclear Research (CERN) say they have measured tiny subatomic particles traveling faster than light.
The difference in speeds is tiny – some 60 billionths of a second over a distance of 454 miles. Even so, if other labs can reproduce the effect, physicists envision one of two far-reaching outcomes.
In one, the CERN team's results could bolster quantum theories of gravity – the last of nature's four fundamental forces scientists are trying to fit under the umbrella of quantum physics. Theories of quantum gravity suggest that at sufficiently high energies, particles can appear to travel faster than light because they traverse extra dimensions of space.
One example is string theory, which posits a universe of many more dimensions than the four humans experience.
"If you have a theory in which there is more than one way to get from A to B, maybe you can have a shortcut and have the appearance of traveling faster than the speed of light," says Stephen Parke, who heads the theoretical physics department at the Fermi National Accelerator Laboratory in Batavia, Ill.
The alternative? A pillar of modern physics – Einstein's theory of special relativity, in which the speed of light is a particle's absolute speed limit – could take its first serious hit. Perhaps not flat wrong, but only a piece of a more complete picture.