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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The most terrifying thing about Donald Trump's speech? What he didn't say

No politician uses official speeches to put across their most controversial ideas. But Donald Trump's are not hard to find. 

As Donald Trump took the podium on a cold Washington day to deliver his inauguration speech, the world held its breath. Viewers hunched over televisions or internet streaming services watched Trump mouth “thank you” to the camera, no doubt wondering how he could possibly live up to his deranged late-night Twitter persona. In newsrooms across America, reporters unsure when they might next get access to a president who seems to delight in denying them the right to ask questions got ready to parse his words for any clue as to what was to come. Some, deciding they couldn’t bear to watch, studiously busied themselves with other things.

But when the moment came, Trump’s speech was uncharacteristically professional – at least compared to his previous performances. The fractured, repetitive grammar that marks many of his off-the-cuff statements was missing, and so, too, were most of his most controversial policy ideas.

Trump told the crowd that his presidency would “determine the course of America, and the world, for many, many years to come” before expressing his gratefulness to President Barack Obama and Michelle Obama for their “gracious aid” during the transition. “They have been magnificent," Trump said, before leading applause of thanks from the crowd.

If this opening was innocent enough, however, it all changed in the next breath. The new president moved quickly to the “historic movement”, “the likes of which the world has never seen before”, that elected him President. Following the small-state rhetoric of his campaign, Trump promised to take power from the “establishment” and restore it to the American people. “This moment," he told them, “Is your moment. It belongs to you.”

A good deal of the speech was given over to re-iterating his nationalist positions while also making repeated references to the key issues – “Islamic terrorism” and families – that remain points of commonality within the fractured Republican GOP.

The loss of business to overseas producers was blamed for “destroying our jobs”. “Protection," Trump said, “Will lead to great strength." He promised to end what he called the “American carnage” caused by drugs and crime.

“From this day forward," Trump said, “It’s going to be only America first."

There was plenty in the speech, then, that should worry viewers, particularly if you read Trump’s promises to make America “unstoppable” so it can “win” again in light of his recent tweets about China

But it was the things Trump didn't mention that should worry us most. Trump, we know, doesn’t use official channels to communicate his most troubling ideas. From bizarre television interviews to his upsetting and offensive rallies and, of course, the infamous tweets, the new President is inclined to fling his thoughts into the world as and when he sees fit, not on the occasions when he’s required to address the nation (see, also, his anodyne acceptance speech).

It’s important to remember that Trump’s administration wins when it makes itself seem as innocent as possible. During the speech, I was reminded of my colleague Helen Lewis’ recent thoughts on the “gaslighter-in-chief”, reflecting on Trump’s lying claim that he never mocked a disabled reporter. “Now we can see," she wrote, “A false narrative being built in real time, tweet by tweet."

Saying things that are untrue isn’t the only way of lying – it is also possible to lie by omission.

There has been much discussion as to whether Trump will soften after he becomes president. All the things this speech did not mention were designed to keep us guessing about many of the President’s most controversial promises.

Trump did not mention his proposed ban on Muslims entering the US, nor the wall he insists he will erect between America and Mexico (which he maintains the latter will pay for). He maintained a polite coolness towards the former President and avoiding any discussion of alleged cuts to anti-domestic violence programs and abortion regulations. Why? Trump wanted to leave viewers unsure as to whether he actually intends to carry through on his election rhetoric.

To understand what Trump is capable of, therefore, it is best not to look to his speeches on a global stage, but to the promises he makes to his allies. So when the President’s personal website still insists he will build a wall, end catch-and-release, suspend immigration from “terror-prone regions” “where adequate screening cannot occur”; when, despite saying he understands only 3 per cent of Planned Parenthood services relate to abortion and that “millions” of women are helped by their cancer screening, he plans to defund Planned Parenthood; when the president says he will remove gun-free zones around schools “on his first day” - believe him.  

Stephanie Boland is digital assistant at the New Statesman. She tweets at @stephanieboland