We still don’t really know how bicycles work

Forget mysterious dark matter and the inexplicable accelerating expansion of the universe; the bicycle represents a far more embarrassing hole in the accomplishments of physics.

Let’s be honest, a bit of the pleasure at Chris Froome’s victory in the Tour de France is down to this being our second victory in a row and to the thought that the French haven’t won it since 1985. What must be worse for them, though, is that when it comes to the science of team cycling, even the Belgians are in front.
 
At the University of Mons, researchers are developing something called the Anaconda. It’s never going to be much of a speed machine because it is, in effect, a chain of monocycles with handlebars. These units are connected, by means of hinges that allow them to snake along, to a normal two-wheeled bike at the front. Every rider in the chain can be going in a slightly different direction, which means it takes an enormous amount of control and collaboration to move the thing forward. According to Olivier Verlinden, chief engineer on the project, the main qualification for riders is to be unafraid of falling off.
 
It’s fun, apparently. The idea is to unleash it as a beach-resort bike, the kind of thing that stag and hen parties will use to terrorise seaside towns across the world. But it is also scientifically interesting. Why? Because we still don’t really know how bicycles work.
 
It is rare that most people appreciate the bicycle, but it is quite an extraordinary machine. Push a riderless bike, letting it roll freely at high enough speeds, and it can withstand pushes from the side – it will wobble a little, but quickly recover. In the conventional analysis, that is because the gyroscopic force of the front wheel, its mass and the spontaneous turn of the handlebars all act together to keep the bicycle rolling forwards. This has something to do with the gyroscopic effect, the force that keeps a spinning top upright. You can feel this by removing a wheel from your pushbike and spinning it while you hold the axle spindles. If you try to change the orientation of the wheel, you’ll feel it push back against you.
 
The first mathematical analysis of bicycles suggested that this is also what keeps a moving bike on its wheels. But although the equations were written down in 1910, physicists always had nagging doubts about whether this was the whole story.
 
The most definitive analysis came exactly a century later. It involved an experimental bicycle that had all its gyroscopic effects cancelled out by a system of counter-rotating wheels. The effort of building such a strange contraption was worth it: the resulting paper was published the prestigious journal Science.
 
The publication plunged bicycle dynamics back into chaos. It turns out that taking into account the angles of the headset and the forks, the distribution of weight and the handlebar turn, the gyroscopic effects are not enough to keep a bike upright after all. What does? We simply don’t know. Forget mysterious dark matter and the inexplicable accelerating expansion of the universe; the bicycle represents a far more embarrassing hole in the accomplishments of physics.
 
And it may not be solved any time soon; very few researchers are working full-time on bicycle dynamics and there’s very little money in it. Once we’ve discovered exactly how these contraptions work, it might be possible to come up with bold new designs of bicycle – perhaps even better than the Anaconda. But nobody is desperate for that to happen; not even the French.
 
Maybe that’s OK. In an age where we have worked out the history of the cosmos and the secret of life, it’s rather nice that the humble bicycle keeps our feet on the ground. 
 
Cyclists during the Tour de France. Photo: Getty

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 29 July 2013 issue of the New Statesman, Summer Double Issue

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Like many others, Dr Hadiza Bawa-Garba was left in charge of a failing aircraft

Ony when enough hospitals shut down, and do so often, will those with true responsibility properly resource the NHS. 

The day Leicester trainee paediatrician Dr Hadiza Bawa-Garba was struck off by the High Court for her involvement in the death of six-year-old Jack Adcock, Health Secretary Jeremy Hunt posted a tweet expressing his deep concern about possible unintended consequences of the ruling. He was referring specifically to the impact on patient safety.

At a stroke, efforts to build a culture of open learning – a cause Hunt champions – had been set back decades. You don’t get people to talk honestly about critical mistakes by threatening them with prison and professional ruin.

There may be other consequences that Hunt didn’t anticipate. Comparisons with another safety-critical industry – aviation – are instructive. On the day Jack died, from undiagnosed sepsis, Bawa-Garba was functioning as would a first officer on an aircraft. The plane’s captain was elsewhere, training other pilots on a simulator in a different city. The chief steward had failed to report for duty, so Bawa-Garba was expected to oversee cabin service as well as fly the plane single-handed.

The aircraft’s IT systems had gone down, meaning one of the stewardesses was permanently occupied looking out of the window to ensure they didn’t collide with anything. Another stewardess was off sick, and her replacement was unfamiliar with the type of plane and its safety systems. And Bawa-Garba herself had just returned from a year’s maternity leave. She’d done quite a lot of flying in the past, though, and the airline clearly believed she could slot straight back into action – they arranged no return-to-work programme, dropping her in at the deep end.

Not one of us would agree to be a passenger on that flight, yet that kind of scenario is commonplace in hospitals throughout the country. Critically ill patients have no awareness of how precarious their care is, and would have no choice about it if they knew. Since the Bawa-Garba ruling, doctors have been bombarding the General Medical Council (GMC) for advice as to what they should do when confronted with similarly parlous working conditions.

The GMC’s response has been to issue a flowchart detailing whom medics should tell about concerns. But it has failed to confirm that doing so would protect doctors should a disaster occur. Nor does it support worried doctors simply refusing to work under unsafe conditions. This is akin to telling the first officer they must inform the airline that things are bad, very bad, but that they still have to fly the plane regardless.

Jeremy Hunt has responded to the crisis by announcing an urgent review into gross negligence manslaughter, the offence of which Bawa-Garba was convicted. This is welcome, and long overdue, but it still serves to retain the focus on individuals and their performance, and keeps attention away from the failing systems that let down doctors and patients daily.

An action by the British Association of Physicians of Indian Origin is, arguably, more important than Hunt’s review. The organisation has written to Leicestershire police requesting that they investigate Bawa-Garba’s hospital trust for alleged corporate manslaughter. I sincerely hope a prosecution follows. I’m no fan of litigation, but change is only going to come when those who manage the NHS know that they are going to carry the can when things go wrong.

We need clear statements of what constitute minimum acceptable staffing levels, both in terms of numbers, and training and experience. When departments, or even whole hospitals, fall below these – or when unexpected problems such as IT failures occur – managers, faced with the real prospect of corporate lawsuits, will close the unit, rather than keep operating in unsafe conditions, as routinely occurs.

Only when enough hospitals shut down, and do so often, will those with true responsibility – Jeremy Hunt and the rest of the Conservative government – finally act to resource the health service properly. 

This would be an unintended consequence from the Dr Bawa-Garba case that would be welcome indeed. 

This article first appeared in the 15 February 2018 issue of the New Statesman, The polite extremist