The CERN team's observation "is a pretty revolutionary result. There will be a lot of people who are skeptical about it in the community, and rightfully so," Dr. Parke says. "Other people need to redo this experiment and see whether they get similar results."
The particles involved are neutrinos, fiendishly difficult to work with because they rarely interact with matter. Thus particle accelerators must produce them in vast quantities in order to spot rare interactions with detectors when they do occur.
They come in three types, and the experiment the team was running – dubbed OPERA – was designed to track neutrinos as they morph from one type to another as they travel.
The team generated beams of neutrinos at CERN, which straddles the French-Swiss border. They aimed the beams at detectors in a cavern at Gran Sasso, Italy, some 450 miles away. With a set of detectors at CERN, and another at Gran Sasso, the team was measuring the neutrinos' travel time between the two. That's when the discrepancy began to emerge.
Rumors of the results have been circulating in the physics community for several weeks, Parke notes. But word leaked more broadly. A draft research paper describing the experiment, results, and efforts to rule out glitches is expected to be posted on the Internet Thursday night. In addition, OPERA scientists are holding a talk at CERN Friday to shed more light on what the team found and the process it underwent to eliminate sources of error in its results.
"We tried to find all possible explanations for this," said Antonio Ereditato, a member of the OPERA collaboration in an interview with the BBC. After hunting for all the mistakes, large and small, the team could think of, it didn't find any.