WE KNOW the sun will rise every day. Or will it? It always has but will it always continue to do so? Evolution is an established fact, but if we have confidence in what it propounds then why do we call it a theory? Scientists can be tricky people to pin down. They steer clear of absolute statements about future events, not that they fear the sun won’t rise or evolution will be halted. Rather, it is because a fact is only a fact once there is evidence to prove it. Just such a tussle between presumption and confirmation in the scientific world has unfolded over recent months.
One of the great immovable monoliths of scientific thinking is that the universe applies an absolute speed limit for movement of any particle, wave or information through space, the speed of light. The great physicist Albert Einstein explained why nothing can ever exceed light speed in his Special Theory of Relativity. This assumption is now fundamental to the mathematical and theoretical constructs used by physicists to describe the shape, scope and future of our universe.
Last September, however, researchers in Italy conducted experiments involving tiny subatomic particles called neutrinos and measured their velocity as in excess of light speed. So monumental were the consequences that the scientists repeated and repeated their tests, eventually clocking their neutrinos as exceeding light speed by 60 billionths of a second. A matter of nothing you might think, less than the speed of a thought. And yet if light speed can be exceeded, even under special circumstances, then what else is open to question?
There then began a process of examination to find whether there were flaws in the experimental devices assembled to study the neutrinos or the scientists had actually found an exception for the light speed limit. We received a partial answer to that question on Thursday, but the matter is yet to be settled finally. The researchers discovered a faulty coupling that connected a fibre-optic cable to the equipment. They also found that the equipment’s own internal clock was running at the wrong speed. Unfortunately the cable issue would make the neutrinos appear to run faster while the clock problem would make them seem to move slower than light speed. A conclusion to the matter will come in May after repairs are made and the experiments are repeated. Then we will learn whether Einstein’s theory stands or falls.