In my last post I wrote about the disappearance of the ‘blip’ in the data from the LHC, a blip that implied they might have discovered a new type of particle. As I wrote I was reminded of another effect that disappeared a few years ago. To me, it was a wonderful demonstration of how the scientific method works and how science corrects itself. Unfortunately, others saw it as a validation of whatever crackpot theory they happened to hold dear. The story goes like this…
In December of 2011 Professor Antonio Ereditato held a press conference. He was the Experiment Coordinator at the Gran Sasso underground laboratory in Italy and what he was about to say would cause a furore, not so much in the world of physics but most certainly in the world’s media. He announced that the OPERA collaboration had made measurements showing that neutrinos travelled faster than the speed of light.
As we well know, nothing can travel faster than the speed of light. In 1905 Einstein revolutionised, erm, everything when he published his theory of Special Relativity. Doing not much more than having a good old think about how the universe works he came up with one of the most fundamental theories of the modern age. It is truly the bedrock of physics and has been tested, and found to be completely accurate, perhaps more than any other theory.
The fact, and despite the story I’m relating to you I think we can call it a fact, that nothing can travel faster than the speed of light isn’t just a shortcoming of our measurements; it is nothing less than an elemental property of the universe. Nothing that has mass can get to the speed of light and anything that is massless travels at the speed of light, no faster.
At CERN, near Geneva, there was a beam of neutrinos that was fired towards Gran Sasso, the distance between the two was calculated to an accuracy of 20 cm but for our purposes the pair were 732 km apart. As speed is equal to distance divided by time we can calculate the speed of the neutrinos if we can accurately measure the time it takes them to complete their journey. Professor Ereditato had gathered the world’s media to tell them that they had measured neutrinos arriving 60.7 nanoseconds before a beam of light would have.
So what was going on? Why was this press conference happening? Did Ereditato genuinely think that his team had done what no one else had in a century of trying and disproved Einstein? I think that’s rather unlikely. I doubt any serious physicist thought that the result was real, Special Relativity is too well tested to be thrown out of the window after one anomalous result.
The team at Gran Sasso had tried to find all sources of potential error in their data but had returned empty handed. They were stumped, but they still weren’t ready to claim that the cosmic speed limit had been broken. In the initial press conference ‘words of caution’ were heavily emphasised, “We tried to find all possible explanations for this,” Ereditato said. “We wanted to find a mistake… and we didn’t… now I’m forced to go out and ask the community to scrutinise this.”
This was completely the right thing to do. Although there is fierce competition in science it is also a collaborative effort. A crucial part of the scientific method is to inspect the data of others and see if it can be reliably replicated. If other groups ran similar tests and found the same result then it would add credence to the data. Also, throwing the problem open to the wider scientific community might give them some pointers as to where they went wrong.
The physics community received the data with the appropriate scepticism and set about rooting out the cause of the anomaly. By June of 2012 two potential sources of error had been discovered. One of the clocks that was used to measure the time taken for the journey was not functioning within parameters and, most crucially, there was a faulty connection in a fibre optic cable that slowed the flight time of the neutrinos by a significant 73 nanoseconds. With these two errors identified and corrected the faster-than-light neutrinos disappeared.
This, for me, is a wonderful demonstration of the self-correcting nature of science and how the community, eventually, will get to he truth of the matter. If this story had stayed within the science community then little more would have come of it, the press conference changed all that, though.
At the best of times science reporting is shoddily done these days. Newspapers and other media don’t think they have the budget to pay writers with a scientific background to write their science stories. Science is just left to English and Journalism graduates who wouldn’t know a tau from a muon neutrino if it was accelerated towards them at 99.99999% the speed of light. It’s necessary to go to specialist science news sites to know what’s really going on.
So it was that the media outlets of the world reported that:
Speed of light ‘broken’ at CERN, scientists claim – Telegraph
Faster than light particles found, claim scientists – Guardian
‘Faster Than Light’ Particles Make Time Travel Possible, Scientist Says – Fox News
Who all these scientists are that are making these claims is never made fully clear. The public, then, were being presented with the sensational claim that Einstein had been proven wrong, that things can travel faster than light and that time travel will, presumably, be the inevitable next step. No doubt they were confused when only 6 months later they are being told that the result was ‘wrong’, that the cosmic speed limit remains intact and superluminosity remains forbidden by the universe.
What are they to make of this? Most people tend to trust their news source of choice, that’s why they pick it every day so it can’t be the newspaper’s fault. Obviously it’s the scientist’s fault, then. They got it wrong, they don’t know what they’re talking about. They’re always changing their minds anyway, best not to pay them any attention. Once this small step to dismissing reality is embarked upon it is not an overly strenuous extra step to begin filling in your own version of reality. This is much better, people think, everything makes sense now. A little bit of social smoking won’t hurt me. Global warming probably won’t do me any harm.
It’s a phenomenon that seems to be spreading in recent times, or perhaps we just notice it more now that it has a name. It is said we now live in a post-truth world where reality doesn’t matter – what’s more important is how people feel. Violent crime is down globally but people feel less safe and so the rule of law is apparently under threat. Immigrants can be shown to add to the GDP of the country they move to but people feel like al the best jobs go to immigrants and so they must be restricted from arriving.
This post-truth attitude has been most prominent during the UK referendum to leave the EU and is ongoing in the US Presidential election. I realise I have strayed a long way from faster-than-light neutrinos here but I think it is a point worth making. Much of the public seems to have lost all trust in experts, especially when the experts are saying something they don’t want to hear. Naturally, as soon as someone needs heart surgery they want the best experts money can buy opening them up. It points at an inherent selfishness that I find distasteful, a selfishness that is counter to all the ideals of science and its pursuit of truth through experimentation, peer review, scepticism and collaboration. Science, done properly, is a beacon of light in a storm that only seems to be raging all the stronger.