In their quest to understand the secrets of the universe, physicists are about to launch their biggest experiment. Next Wednesday, the first atoms will race round a 27km track beneath the Swiss-French border outside Geneva, at almost the speed of light.

It will be the first step towards the real moment of truth for the $8bn (£4.5bn, €5.6bn) Large Hadron Collider. In a few weeks, two beams of protons – hydrogen nuclei – will accelerate in opposite directions and smash together, creating in miniature the intense energies of the newborn universe just after the “big bang” some 14bn years ago.