(Image: Richard Giles)

HOW quickly would Usain Bolt have run the 100 metres at the Beijing Olympics if he hadn’t slowed in celebration before the finish line? A team of physicists have calculated an answer: the Jamaican gold medallist could have slashed his time from 9.69 seconds to 9.55 seconds.

In the final 20 metres of the race on 16 August, Bolt extended his arms and thumped his chest in celebration, slowing himself a little. But he still broke the world record he himself had set in May.

Hans Eriksen of the Institute of Theoretical Astrophysics at the University of …