The flight boarding challenge has been solved by maths, but people are not numbers, writes ARTHUR GOLDSTUCK. In 2008, astrophysicist Jason Steffen published a mathematical answer to one of air travel’s most persistent irritations: the slow movement of passengers from the boarding gate into their seats. So his solution placed passengers in alternating rows, with window-seat travellers boarding ahead of those booked into aisle seats. By the rules of the model, boarding had been solved. The difference between travel and finances is that, at the boarding gate, the gap between the calculation and the passenger is visible.