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Scientists at the CERN physics laboratory in Geneva, Switzerland, claimed recently to have clocked a subatomic particle, known as a neutrino, traveling faster than the speed of light. If true, the event would violate a central tenet of physics and undermine Albert Einstein's 1905 special theory of relativity. But ascientists at the Fermi National Accelerator Laboratory outside Chicago, Illinois, also known as Fermilab, are not convinced.
Fermilab Scientists, Faster-Than-Light Neutrino Claims, CERN, Einstein, physics, particle accelerator lab
Einstein's special theory of relativity is basic physics to scientist Patrick Fox. "I have been studying that for years. It is something you use day-to-day. And it basically boils down to the statement that physics should be independent of how fast you are moving."
That includes traveling at the speed of light. "The only objects that can travel at the speed of light are massless things, like light," he said.
Scientist Robert Plunkett explains the prevailing wisdom about subatomic particles like neutrinos is that they can accelerate to nearly the speed of light, but never faster. "The speed of light is the absolute cosmic speed limit for the travel of particles," he said.
But scientists in Europe claim they have recorded a neutrino particle that broke that "cosmic speed limit." If true, the discovery would upend almost a century of research, and force scientists to rethink the laws governing mass and movement.
Plunkett is not convinced. Not yet. "Skepticism is something we always bring to the table anytime there is a revolutionary claim like this," he said.
"Before we throw away a cherished principle we have to, of course, check that this result, which is a very interesting result, is confirmed by other sources," said Fox.
One of the "other sources" is the MINOS experiment at Fermilab. Located in a massive underground tunnel, MINOS shoots a particle beam through the earth to another, offsite location. Scientists at the lab clock how fast the particles travel.
"It is likely that the MINOS experiment is one of the best checks that can be done on this measurement," said Plunkett.
But Plunkett says it is easy to make a mistake when trying to measure something as small as a neutrino. He believes the MINOS facility, with an upgrade, can provide a more precise measure of the CERN results. "Our plans are to upgrade this equipment using a system of atomic clocks, much like what they had in the European experiment, to in fact do a measurement that is more precise than theirs, in many ways," he said.
But if MINOS, too, clocks a neutrino traveling faster than the speed of light, theorists like Patrick Fox will have their work cut out for them, designing a new foundation for future physics research.
subatomic: of or relating to particles that are smaller than an atom [化學] 亞原子的；原子內的
neutrino: any of three electrically neutral subatomic particles in the lepton family 微中子
Einstein Exhibit Opens in New York
（來源：VOA 編輯：Rosy）
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