Physicists love numbers - this week, they are claiming that 43 per cent of UK manufacturing employment is in "physics-based" industries. The figure seems suspiciously precise, but there is no doubt that modern life depends on devices - computers, cars, aircraft, CD players - that derive from the insights of physics. However, the economic importance of physics has not been translated into student numbers.
Growth subjects such as information technology have competed for potential physics students, and newcomers such as media studies have overtaken it in a few years. Physics has a built-in disadvantage of demanding good mathematical skills. It is to be hoped that Adrian Smith's inquiry into mathematics will mean better school maths, which would be positive for physics and for related subjects such as engineering. Physics in schools has also suffered from low awareness among pupils. This is why schemes such as the research councils' Researcher in Residence initiatives, designed to show 14 to 16-year-olds that physicists and other scientists are normal people having interesting lives, are to be applauded.
But although physicists are correct to say that there would be no satellite TV and no internet without them, people in more fashionable subjects such as finance, marketing and design are entitled to reply that, in themselves, discoveries generate no employment. This is why the Institute of Physics is to be applauded when it calls for physics students to get more idea of the business context in which their science might turn into money.
Pharmaceutical companies have led the way by showing that good careers and salaries await good students. The physics-based industries should do the same.
But changing the curriculum will not be easy. Turning undergraduate physicists into second-rate business students will not help. And one of the most frequent complaints raised by science and engineering students is that their timetable is already crammed compared with that of arts students. Of course, undergraduate physicists should know more about the profit potential of their work, but steps should be taken to ensure they see the subject in its full social setting. Nuclear power, weapons manufacturing and fossil-fuel burning are among the physics-based industries, as are renewable energy and public transport. Open discussion of these might attract more students than learning how to draw up a business plan.