The world's biggest atom accelerator near Geneva has restarted. The Large Hadron Collider had been shut down just days after its inauguration in September 2008 due to a series of technical faults.

The 27-kilometre tunnel straddling the Franco-Swiss border was found to leak liquid helium. Tests of injecting sub-atomic particles into the tunnel are expected to run at full capacity early next year. The machine has been designed to replicate conditions reigning just after the Big Bang. Particle physicists at CERN hope the accelerator will shed new light on the origins of the universe.

(Photo: EPA)