Francisco Perez-Reche: No fidgeting in class, but the viral maths adds up

It is likely that you have seen a fidget spinner recently, or have heard about them. If not, a quick search on the web will convince you that they are really popular toys.

Children find it hard to explain why they love fidget spinners. Picture: John Devlin

The fidget spinner idea has been around since the 1990s but their popularity has increased at an astonishing rate only in the last months. Most children love them: They can do tricks and some even argue that spinners help them concentrating during lessons. In fact, there have been claims about the spinners’ soothing effects for both children and adults but no evidence has been reported so far.

Either way, fidget spinners have been banned in many school classes over injury fears and distraction of pupils. They’ve also been in the news. “A physicist warns that fidget spinners could affect Earth’s center of gravity” is fake news. In contrast, the appearance of “razor sharp” fidget spinners is a fact and is very bad news.

Fidget spinners are a global phenomenon and it is remarkable that such a simple toy can become so trendy overnight.

As a scientist, I think they represent an interesting social phenomenon and also have fascinating physics behind them.

Many adults do not get the point of spinners and some children find it hard to tell why they like them so much. One may then wonder why are they so popular and why demand for them has risen so quickly. Another interesting question is why it took about 20 years for their popularity to blow up.

Many features of the fad align well with our theory on explosive social contagion – or why things “go viral”.

Using a mathematical model, we showed that people’s lack of interest in a new product acts as a barrier to large contagion. The barrier delays the acceptance of the product. The surprising prediction of our model is that this delay goes on to promote explosive contagion once the interest in the product reaches a minimal level – at this point, imitation overcomes the lack of appeal.

The prediction may look paradoxical. However, it is mathematically robust and captures key traits of many popular products, ideas, etc. Examples range from the fidget spinner trend to the fame of the Beatles after an infamous initial rejection or the sudden popularity of some social movements.

From the perspective of physics, I see fidget spinners as an opportunity to illustrate the rotation of solid bodies. For instance, what would happen if the Earth spun the other way? One can neatly demonstrate an interesting consequence by just attaching a string to a fidget spinner.

I have done this in a primary school and pupils seemed to enjoy the trick – I hope they also learned something. Incidentally, spinners are banned at that school, but the ban doesn’t apply if they are used in the name of science and education.

Francisco Perez-Reche is lecturer in Physics and Life Sciences, University of Aberdeen