One of Einstein’s fundamental laws of the universe is being questioned after researchers at the Centre for Nuclear Research (CERN) in Switzerland observed sub-atomic particles moving faster than the speed of light.
Did you know? The speed of light in vacuum is a physical constant equal to 299,792,458 metres per second. This value is defined based on the length of a metre and a standard unit of time.
Scientists involved in the Oscillation Project with Emulsion-tRacking Apparatus (OPERA) sent sub-atomic particles called neutrinos from CERN in Switzerland to the Gran Sasso facility in Italy–a 730-kilometre trip. The experiment was repeated for a total of 15,000 neutrinos over three years and the final results showed that the neutrinos arrived in Italy 60 billionths of a second faster than light would have.
Did you know? Neutrinos are electrically neutral sub-atomic particles that only very weakly interact with matter and can thus travel great distances through solid materials.
In any experiment, potential errors are involved and must be accounted for. For this project, scientists estimated an error margin of 10 billionth of a second, which still does not account for the difference in arrival times.
Let us assume for a moment that it is indeed possible for particles with mass to travel faster than the speed of light. What are the implications?
Perhaps the most troubling consequence is that in order to travel faster than the speed of light, one must to travel backwards in time. And, while science fiction has made this a popular, even feasible concept, it is a hard pill to swallow for scientists.
Did you know? Einstein’s theories of special and general relativity mathematically explain the concept of travelling backwards in time, but we do not know whether the laws of physics would allow for this to become a reality.
Subir Sarkar, head of particle theory at Oxford University said: “The constancy of the speed of light essentially underpins our understanding of space and time and causality, which is the fact that cause comes before effect.”
Imagine, for example, your friend catching a ball that you have not yet thrown to her. Without cause (you throwing the ball) how can there be effect (your friend catching the ball)? If this fundamental law of the universe is flawed, then our entire understanding of physics and the world also falls apart.
Let us assume that Einstein was right and nothing can travel faster than the speed of light. How do we explain the experimental findings at CERN?
Scientists on the project are currently welcoming the scrutiny of their findings, and hundreds of ideas have emerged. Neutrinos are still mysterious particles to us, perhaps we do not know enough about them to accurately explain their behaviour in this experiment. Or perhaps there exists a higher dimension through which the neutrinos travel before reaching Gran Sasso.
Researchers are continuing to explore ways to disprove their experimental results because if Einstein was wrong, then how can we be sure of anything at all?
How the Neutrino Experiment Works
Faster-Than-Light Result to Be Scrutinized
Time Travel and Einstein's Relativity Made Easy
How the Speed of Sound and Light Was Discovered
Article first published November 9, 2011