Splitting sausages, immigration and the “Silence of the labs”

A hot topic this week. (Courtesy: Shutterstock/indigolotos)

By Hamish Johnston

Why do sausages usually split lengthwise when cooked? That’s the subject of a fantastic article on Gizmodo that applies physics and maths to answer this important culinary question. Full of diagrams, a dozen equations and an evocation of Pascal’s principle, the article concludes that the “hoop stress” on the casing, which tends to cause lengthwise splits, is double that of the stress in the perpendicular direction. The article was adapted from a piece by the blogger Nick Berry about why pipes usually split lengthwise when frozen.

Immigration is a topic that is splitting public opinion in the UK as the government attempts to reduce the number of foreigners entering the country to work. Ongoing changes to the rules seem to be having negative effects on researchers and those who employ them. In an article in the Times Higher Education the Canadian academic Adam Barker describes what is becoming a common story. Despite having been married to a UK citizen for 10 years, Barker had a job offer from a UK university revoked because of changes to immigration policy. And to add insult to injury, when he tried to gain the visa that he now needs he was turned down. He has now decided to return to Canada while his wife finishes her PhD in the UK.

In this month’s issue of Physics World, Jeremy Good looks at UK immigration policy from the perspective of an employer. Good is the chief executive of Cryogenic Ltd, which is a hi-tech company that counts scientists among its employees and customers. As well as making it more difficult to hire skilled scientists and engineers from outside Europe, Good points out that UK policy is also jeopardizing sales because potential customers in some countries are being denied visas to visit the firm. You can read Good’s article and much more in the digital version of the magazine, which you can access free if you’re a member of the Institute of Physics. Remember that if you’re not yet a member, you can join the Institute as an IOPimember for just £15, €20 or $25 a year.

Canada has come through the recent recession relatively unscathed so you might think that Adam Barker and other academics face a rosy future there. Not so, at least according to some researchers who have been complaining for several years now about the apparently anti-science policies of Canada’s Conservative government. In the past five years more than 2000 scientists working for the federal government have been made redundant while some of the scientists who remain have complained that they are not allowed to talk to the public about their research. Others have alleged that scientific studies in topics such as pollution, food safety and climate change have been disproportionally targeted by spending cuts.

Tonight the Canadian Broadcasting Corporation (CBC) television series The Fifth Estate is airing an episode entitled “Silence of the labs” that looks at the state of science in Canada. You can watch a trailer for the programme here  and it looks like the full programme will be available on the CBC’s player after broadcast.