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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Theresa May’s Brexit speech is Angela Merkel’s victory – here’s why

The Germans coined the word “merkeln to describe their Chancellor’s approach to negotiations. 

It is a measure of Britain’s weak position that Theresa May accepts Angela Merkel’s ultimatum even before the Brexit negotiations have formally started

The British Prime Minister blinked first when she presented her plan for Brexit Tuesday morning. After months of repeating the tautological mantra that “Brexit means Brexit”, she finally specified her position when she essentially proposed that Britain should leave the internal market for goods, services and people, which had been so championed by Margaret Thatcher in the 1980s. 

By accepting that the “UK will be outside” and that there can be “no half-way house”, Theresa May has essentially caved in before the negotiations have begun.

At her meeting with May in July last year, the German Chancellor stated her ultimatum that there could be no “Rosinenpickerei” – the German equivalent of cherry picking. Merkel stated that Britain was not free to choose. That is still her position.

Back then, May was still battling for access to the internal market. It is a measure of how much her position has weakened that the Prime Minister has been forced to accept that Britain will have to leave the single market.

For those who have followed Merkel in her eleven years as German Kanzlerin there is sense of déjà vu about all this.  In negotiations over the Greek debt in 2011 and in 2015, as well as in her negotiations with German banks, in the wake of the global clash in 2008, Merkel played a waiting game; she let others reveal their hands first. The Germans even coined the word "merkeln", to describe the Chancellor’s favoured approach to negotiations.

Unlike other politicians, Frau Merkel is known for her careful analysis, behind-the-scene diplomacy and her determination to pursue German interests. All these are evident in the Brexit negotiations even before they have started.

Much has been made of US President-Elect Donald Trump’s offer to do a trade deal with Britain “very quickly” (as well as bad-mouthing Merkel). In the greater scheme of things, such a deal – should it come – will amount to very little. The UK’s exports to the EU were valued at £223.3bn in 2015 – roughly five times as much as our exports to the United States. 

But more importantly, Britain’s main export is services. It constitutes 79 per cent of the economy, according to the Office of National Statistics. Without access to the single market for services, and without free movement of skilled workers, the financial sector will have a strong incentive to move to the European mainland.

This is Germany’s gain. There is a general consensus that many banks are ready to move if Britain quits the single market, and Frankfurt is an obvious destination.

In an election year, this is welcome news for Merkel. That the British Prime Minister voluntarily gives up the access to the internal market is a boon for the German Chancellor and solves several of her problems. 

May’s acceptance that Britain will not be in the single market shows that no country is able to secure a better deal outside the EU. This will deter other countries from following the UK’s example. 

Moreover, securing a deal that will make Frankfurt the financial centre in Europe will give Merkel a political boost, and will take focus away from other issues such as immigration.

Despite the rise of the far-right Alternative für Deutschland party, the largely proportional electoral system in Germany will all but guarantee that the current coalition government continues after the elections to the Bundestag in September.

Before the referendum in June last year, Brexiteers published a poster with the mildly xenophobic message "Halt ze German advance". By essentially caving in to Merkel’s demands before these have been expressly stated, Mrs May will strengthen Germany at Britain’s expense. 

Perhaps, the German word schadenfreude comes to mind?

Matthew Qvortrup is author of the book Angela Merkel: Europe’s Most Influential Leader published by Duckworth, and professor of applied political science at Coventry University.