Large Hadron Collider
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Large Hadron Collider restarts at Cern

The Large Hadron Collider, the world's most powerful particle accelerator, has been restarted, after a two-and-a-half year upgrade.

Researchers at Cern in Switzerland have already discovered the Higgs boson, and now hope to find out more about dark matter.

Science correspondent Pallab Ghosh reports.

  • 05 Apr 2015