A ghostly particle has broken the speed of light, and Einstein’s relativity – scientists claim

by anastasiyakudryashova ’12

“No! There’s no way!” says UAHS AP Physics teacher Jeff Schuster, “That’s not what I believe!”

Sept. 23, 2011 the impossible was announced: modern physics was broken, one of the 20th century’s greatest minds rebuffed, and time came to a standstill. The scientific community was in a frenzy of excitement and dismay.

But, as many physicists now claim, the trailblazing discovery is turning out to be just another awkward false alarm…

CERN, the European Organization for Nuclear Research, famed for its experiments with the Large Hadron Collider, has made yet another perplexing discovery. This summer, scientists at CERN had consistently measured neutrino particle beams, subatomic particles with masses so small they have yet to be precisely determined, to exceed the speed of light by 60 nanoseconds (a statistically significant number) – something that should not be possible, as far as modern science tells us.

CERN researchers, having extensively verified the experiment over the months preceding the press release, finally disclosed the results in September inviting peer review of their experiment. And criticism came, by the handful.

By now, the consensus is that a systematic error was responsible for the upheaval, but that doesn’t mean the inquiry was worthless. The resulting enthusiasm, which reached far beyond the professional community of nuclear physicists into the general public, will provide impetus for new challenges and ideas. Meanwhile, scientists across the spectrum can learn from the mistakes.

Light, Time, and Einstein

With most objects, the frame of reference matters with regard to their relative motion. Light is the exception. The speed of light in vacuum is always 670 million mph, regardless if you (the observer) are moving towards the light or away from it. In order to explain the phenomenon, Albert Einstein in his special theory of relativity developed the famous E=mc2 and claimed that the speed of light is the speed limit of the universe.

The key difference between photons, the bundles that make up light, and all other matter is that photons are massless at rest (and have indeterminate mass when moving at light speed). Any object that has mass, no matter how small, would require an infinite force on an infinite mass to surpass the speed of light.

Since neither infinite mass nor infinite force is possible, Einstein believed that the speed of light could not be broken. The neutrino – one of the fundamental particles of the universe, orders smaller than even the electron – nonetheless has mass, and should thus abide by Einstein’s relativity.

What’s more, as an object approaches the speed of light, time slows down. As San Jose State University computer science student Yu Song says, we don’t know what would happen if the speed of light was actually breached: time could be at a standstill. “It would just break down and wouldn’t exist.” Or, it could move backwards!

MIT physicist Seth Lloyd said in an interview for LiveScience that neutrinos, if they really did surpass the speed of light, could be used to send messages into the past – whether they’d be noticed or not is a different question.

Faster Than Light

If we can really measure faster than light speeds with certainty, in this experiment or in the future, the consequences would not bear lightly on the future of physics.

“All the Physics text books in the world would have to be changed,” Schuster said. This does not apply to the hard-rock foundation of Galileo and Newton, but if Einstein’s theory of relativity is proven inadequate, nearly all of modern physics (most of the discoveries since Einstein, based strongly on relativity) would have to be reworked.

If Einstein's relativity cracks, modern physics is in danger

If Einstein's relativity is cracked, all of modern physics is in danger. Graphic by: Anastasiya Kudryashova. Source: Jeff Schuster.

This can either be seen as a major setback, or as an opportunity to move physics towards new realms.

University of Pennsylvania junior and Astrophysics major Thomas Krane says “who knows what the scientific implications would be if Einstein is proven wrong about relativity. Maybe it means that we could find a way to go faster than the speed of light – reach distant galaxies in seconds, travel through time itself.”

Palisades Charter High School senior Elliot Chou is likewise excited by the idea of hyperspeed travel, or FTL as “Faster Than Light” speed is known in the world of sci-fi. “In the future, we will eventually expand beyond Earth, and the expansion of humanity includes everyone,” Chou says, “It would speed up the expansion into space, and I might be able to get involved with that.”

No one really knows what breaking the “speed limit of the universe” would entail. Theoretical string physicist Michio Kaku goes as far as to say in an article in Big Think that we would have to wait for a new “Einstein” to fill in the gaps in relativity. Certainly, it would mean a new age for physics.

Not So Fast…

It seems like now, however, is not the time.

The scientific community was skeptical from the outset.

“When you are told something like that for over 30 years, you start to believe it. Not just think it’s true because of experimental evidence, but to really have faith that the speed of light is the speed limit of the universe,” Shuster said, “so when someone comes up with experimental evidence that the speed of light has been broken, I feel like my faith is being attacked.”

The university atmosphere, too, was fraught with doubt.

“The first thing I said was ‘it must be a systematic error,’ ” Krane said, “and [my professor] agreed and said that’s basically what all the professors think too.”

The mass of a neutrino particle is very small, so it is expected to travel at nearly the speed of light – and the result was a mere 60 nanoseconds (billionths of a second) faster, not leaving much room for a margin of error.

And besides, earlier observations of supernova explosions – which release large numbers of neutrino particles – demonstrate the opposite point. Neutrinos travel slightly below light speed.

Nearly a month following the CERN press release, University of Groningen physicist Ronald van Elburg claimed that he had found the error, and many of his colleagues agree.

The slip-up lies in relativity. Both time and distance were measured by GPS satellites in orbit around Earth. But the satellites were also moving with regards to the Earth – a factor that wasn’t taken into account, though by Einstein’s theory of relativity, the frame of reference matters.

The calculations redone to account for relative motion, van Elburg calculates it the error to be 32 nanoseconds on both ends (64 nanoseconds total) – enough for the neutrinos to come just short of the speed of light.

“It’s all about relativity,” Yu Song says, and it seems that the team at CERN had introduced more variables than they could keep track of.

If van Elburg’s criticism is correct, which time will tell with peer review, there is an acute sort of irony in this mistake: the discovery that was presumed to have challenged the theory of relativity actually only confirms it.

Even though this solution appears to be a valid one, peer review by independent researchers is necessary before any conclusions can be made. Whether this discovery is confirmed or not, the scientific community has been shaken into a whirl of discussion and enthusiasm. Scientists will be debating theories and possibilities at least until peer review by groups of physicists in Japan and the US is completed, and the echo will reverberate for much longer than that.

The controversial experiment has taught us a thing or two about relativity, and reminded scientists once again of the importance of paying attention to the details. Even more importantly, it has revitalized the field of physics itself. The interest generated in a study previously thought relatively well understood may spark a revolution of new and creative research, attracting fresh minds like Elliot Chou inspired to make their own contribution. Only time will tell.

“Maybe physicists now have a naive sense of security in their knowledge,” Krane said in conclusion, “and I think that there’s something to be said for an experiment that challenges the fundamentals on such a deep level.”

After all, Einstein’s theory of relativity itself had overturned the pillar of Newtonian physics which had gone unquestioned for centuries.