The heads of three major physics labs said Thursday they're skeptical a subatomic particle traveled faster than the speed of light.
The three lab directors spoke two weeks after European scientists said they clocked a neutrino going faster than the 186,282 miles per second _ thought to be nature's speed limit under Einstein's 1905 special theory of relativity.
The European Organization for Nuclear Research, or CERN, on the Swiss-French border, provided the particle accelerator that sent neutrinos on their 454-mile (730-kilometer) trip underground from Geneva to Italy.
There's a good chance the research won't hold up, said Rolf Heuer of CERN, Pier Oddone of Fermi National Accelerator Laboratory, or Fermilab, in the U.S., and Atsuto Suzuki of High Energy Accelerator Research Organization, or KEK, in Japan.
"I'm a complete skeptic," Oddone said.
Suzuki said he also is "expecting" it to turn out to be untrue, while Heuer agreed "one has to be very, very skeptical" until someone else can confirm the findings.
They also shared a growing conviction the elusive Higgs boson _ a theoretical particle that would explain why matter has mass, an enormous scientific breakthrough _ will be found or ruled out within 12 months.
"I think by this time next year I will be able to bring you either the Higgs boson or the message that it doesn't exist," Heuer said, confident because of the reams of new data being generated at CERN's $10-billion Large Hadron Collider near Geneva.
Scientists theorize as part of the Standard Model of how the universe works that the Higgs boson gives mass to other particles, and thus to other objects and creatures in the universe.
The collider also may lead scientists to other discoveries such as seeing dark matter, the strange stuff that makes up more of the universe than normal matter but has not been seen on Earth.
European researchers reported Sept. 22 that a neutrino beam fired from a particle accelerator near Geneva to a lab in Italy traveled 60 nanoseconds faster than the speed of light. The margin of error was 10 nanoseconds, each of which is equal to one-billionth of a second.
France's National Institute for Nuclear and Particle Physics Research collaborated with Italy's Gran Sasso National Laboratory on the neutrino experiment at CERN.
If the work can be replicated, they said, scientists would have to fundamentally alter their explanations of how the universe operates.
The lab directors said there were four possibilities for trying to do that _ in the U.S., Japan, Italy and the world's biggest physics lab on the Swiss-French border.
Oddone said Fermilab hoped to accomplish it by next May.
Much of current scientific understanding is based on Einstein's theory that energy equals mass times the speed of light squared. Already, they agreed, the world seems to be moving beyond it in ways once thought unimaginable.
"Well, who tells you we are only living in three space dimensions? Maybe our imagination is not good enough," Heuer said. "If we find an extra dimension, or a number of extra dimensions, that could bring us much further beyond Einstein.
Oddone said that "in some sense we have moved already beyond Einstein" in our understanding of the universe.
"It's still Einstein's dream of getting to a unified picture of nature," Oddone said. "We really don't know what's out there. And that's why it's so exciting."