World’s largest particle accelerator restarts

The Large Hadron Collider, housed in a 27-km tunnel under the Swiss-French border, has been shut down for three years. It has been undergoing maintenance and upgrades, which were slowed down by Covid-19 © Keystone / Laurent Gillieron

CERN, the European Centre for Nuclear Research on the Swiss-French border, on Friday restarted the world’s largest particle accelerator in a bid to find out more about the origins of the universe.

This content was published on April 22, 2022 - 12:56

The 27-kilometre Large Hadron ColliderExternal link has been out of action since the start of 2019 for maintenance and upgrades, which were slowed down by Covid-19. Restarting it is a complex procedure akin to directing “an orchestra”, where “all the right steps have to be taken at the right time”, CERN scientist Rende Steerenberg told Reuters earlier this week.

It will take six to eight weeks for the machine to run at full speed, and only then will proton collisions take place again, which scientists hope will reveal more about the fundamental laws of the universe.

Collisions observed at CERN between 2010 and 2013 brought proof of the existence of the long-sought Higgs Boson particle which, along with its linked energy field, is thought to be vital to the formation of the universe after the Big Bang 13.7 billion years ago. Physicists hope the resumption of collisions will help in their quest for so-called “dark matter” that lies beyond the visible universe.

The LHC is housed in a 27-kilometre tunnel beneath the French-Swiss border near Geneva and is the world’s largest and most complex scientific instrument. It smashes protons at almost the speed of light, recreating conditions a fraction of a second after the Big Bang 13.7 billion years ago.

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