One of CERN's biggest discoveries has to do with neutrinos. Neutrinos are one of the fundamental subatomic particles that make up our universe. They function somewhat like an electron except for the fact that they cannot carry a charge. While conducting studies on neutrinos in the Large Hadron Collider (which essentially accelerates particles to the speed of light and then forces them to collide), scientists discovered something remarkable: neutrinos can apparently travel faster than light. From the Associated Press:
Scientists at the world's largest physics lab said Thursday they have clocked neutrinos traveling faster than light. That's something that according to Einstein's 1905 special theory of relativity — the famous E (equals) mc2 equation — just doesn't happen.And though this discovery probably doesn't stand out to most people it is a massive discovery for physicists, for it challenges one of the fundamental theories of Albert Einstein's Theory of Special Relativity.
"The feeling that most people have is this can't be right, this can't be real," said James Gillies, a spokesman for the European Organization for Nuclear Research, or CERN, outside the Swiss city of Geneva.
Gillies told The Associated Press that the readings have so astounded researchers that they are asking others to independently verify the measurements before claiming an actual discovery.
Scientists agree if the results are confirmed, that it would force a fundamental rethink of the laws of nature.
Einstein's special relativity theory that says energy equals mass times the speed of light squared underlies "pretty much everything in modern physics," said John Ellis, a theoretical physicist at CERN who was not involved in the experiment. "It has worked perfectly up until now."
"This would be such a sensational discovery if it were true that one has to treat it extremely carefully," said Ellis.
One of the fundamental teachings of Einstein's Theory of Relativity is that nothing in the universe can travel faster than light (approximately 186,287 miles per second). This is important because Special Relativity teaches that time is relative to one's motion and position in space. Simply put, the faster a person is moving, the slower he/she will perceive time.
So if neutrinos really do travel faster than light does that mean they are traveling back in time? I won't even pretend to think that I understand physics well enough to answer this question. But what everyone, expert or not, is recognizing is the fact that if this discovery is true, our understanding of the universe will once again have to change. It will force physicists to reevaluate the notion that light is the "speed limit" of the universe.
But before we all rush out and buy our Deloreans and Flux Capacitors don't get too excited. As is the case with any major alleged scientific discovery, skeptics have questioned these findings. As one physicist states:
The things you need to know about this result are:In other words, verifying that neutrinos are traveling faster than 186,000 miles per second is a difficult thing to do, even with all of the technology and expertise at CERN. Despite these difficulties we can all rest assured that the good folks at CERN will do all they can to get this right. If the finding is true, then we can look forward to improving our understanding of the universe. If not, it just confirms that we already are on the right track. Either way, this alleged discovery does prove one thing right beyond a shadow of a doubt: science is alive and well in our day and age!
- It’s enormously interesting if it’s right.
By the latter point I don’t mean to impugn the abilities or honesty of the experimenters, who are by all accounts top-notch people trying to do something very difficult. It’s just a very difficult experiment, and given that the result is so completely contrary to our expectations, it’s much easier at this point to believe there is a hidden glitch than to take it at face value. All that would instantly change, of course, if it were independently verified by another experiment; at that point the gleeful jumping up and down will justifiably commence. This isn’t one of those annoying “three-sigma” results that sits at the tantalizing boundary of statistical significance. The OPERA folks are claiming a six-sigma deviation from the speed of light.
- It’s probably not right.
But that doesn’t mean it’s overwhelmingly likely that the result is real; it just means it’s overwhelmingly unlikely that the result is simply a statistical fluctuation. There is another looming source of possible error: a “systematic effect,” i.e. some unknown miscalibration somewhere in the experiment or analysis pipeline. (If you are measuring something incorrectly, it doesn’t matter that you measure it very carefully.) In particular, the mismatch between the expected and observed timing amounts to tens of nanoseconds; but any individual “event” takes the form of a pulse that is spread out over thousands of nanoseconds. Extracting the signal is a matter of using statistics over many such events — a tricky business.