The claim by a group of Italian scientists that they have observed faster-than-light travel promises to be the opening act of a dramatic illustration of the way science works.
To understand the plot, you need a little physics.
Early last century, Albert Einstein formulated two theories of relativity — the special and the general — that between them formed the basis of most theoretical physics of the last hundred years. Subsequent experiments backed up Einstein’s work. Relativity works. Without it, we would not have cell phones, GPS, atomic energy, solid-state technology or a host of other high-tech apps.
Now, relativity rests on a very important principle: the speed of light is a limiting constant. It doesn’t matter where you are or how fast you are travelling, if you were to measure the speed of a light beam, going in any direction, it would clock in at just under 300,000 kilometres per second. (299,792,458 metres per second, to be exact). It follows that it is theoretically impossible for an object to exceed this speed.
So much for the basic physics. On with the story.
Along comes OPERA (Oscillation Project with Emulsion-tRacking Apparatus) of the
Gran Sasso National Laboratory in Italy,whose scientists have been tracking neutrino emissions from CERN, Europe’s premier high-energy physics laboratory located 730 kilometres away near Geneva. The OPERA group has observed that the neutrinos — subatomic particles that supposedly travel at light speed — are arriving 60 billionths of a second before they should.
That might not sound like a big deal, but in the world of physics, the slightest deviation from theory means the whole theory is open to question. If the OPERA observations are correct — and OPERA is no basement lash-up run by an unshaven crank — modern physics collapses.
The drama will unfold as physicists home in on the OPERA finding. They will do this in two ways.
First, peer review. The observation has to be vetted by competent physicists and published in a journal. If the referees can find errors in the methods or the calculations the claim is dead.
Second, replication. The experiment has to be repeated by other groups of physicists. This is done in order to detect any errors the referees missed.
Notice that the purpose of these two tests is not to justify the finding. The opposite, in fact. It is to expose weaknesses in the observation.
And that’s how science works. Someone comes up with a new idea or a novel observation and other scientists (including the originator him or her self) tries to disprove it. If the novelty passes the test, science has to find a way of fitting it in with the canon of established knowledge.
Compare this with the way crank beliefs work. The crank comes up with an idea — that the universe was created 10,000 years ago, that water will hold the memory of substance that was once dissolved in it, that the Apollo missions to the moon were faked — and then rushes madly about trying to prop up the shaky hypothesis.The idea of actually testing the hypothesis is absurd to the crank.
It is also common for cranks to complain that scientists ignore or contradict their ideas, that there is a conspiracy to suppress the brilliant idea. Nonsense. If the OPERA finding passes the tests, theoretical physicists will be all over it like grad students lining up for free beer. Academic fame (but unfortunately not fortunes) is made by investigating anomalies like this.
I’ll try to keep you posted. You can read more about the OPERA experiment at Nature News.