If built, the Future Circular Collider (FCC) will form a circular tunnel under the Franco-Swiss border, 91 km long and about 5 meters in diameter, at a depth of 100 to 300 meters underground. It would pass under Geneva, under Lake Geneva and stretch to the city of Annecy, writes AFP.

Antoine Mayeau, an engineer at Cern, explained that technical and scientific ground sites could be located in eight locations, including five in Haute-Savoie, two in Aisne and one in Geneva.

After the theoretical analysis phase, “we are now starting field activities for the first time” to address environmental issues, followed by seismic and geotechnical studies, he said.

Once this major feasibility study is complete, CERN’s 23 member states (22 European countries and Israel) will decide around 2028/2029 to build this facility, which should accelerate electrons and positrons by 2060. and then hadrons until 2090.

The goal is to answer many fundamental questions in physics that remain unanswered even though 95% of the mass and energy of the universe is unknown to us.

The LHC is getting old

Cern already has the world’s largest particle accelerator, the Large Hadron Collider (LHC), a 27-kilometer ring located about 100 meters underground.

“The problem with accelerators is that at some point, no matter how much data you accumulate, you hit a wall of systematic errors. Around 2040-2045, we will eliminate the very essence of precision that we can get from the LHC,” explained Patrick Jano, a physicist at Cern.

“It’s time to move on to something much more powerful, much brighter, to better see the contours of the physics we’re trying to study,” he said.

But some researchers worry that this huge project will eat up funds that could be used for other, less abstract physics research.

Other physicists warn that if fundamental physics is stopped, applied physics will also suffer decades from now.

“The benefits of our research are extremely important,” said Malika Meddahi, Cern’s associate director for accelerators and technologies, referring to medical imaging and the fight against tumors.

Political stability and ambition / China enters the race

“The day I invented the electron gun, which became the beginning of accelerators, I did not know that it would give birth to television. “The day we discovered general relativity, we didn’t know it would be used to power GPS,” Janot added.

Asked by AFP, Harry Cliff, a particle physicist at the University of Cambridge, admitted the FCC was expensive, but “we have to bear in mind that it will be built on a lot of international cooperation over a very long period of time.”

More than 600 institutes and universities around the world use Cern facilities and are responsible for funding, conducting and managing the experiments on which they collaborate.

However, CERN is not the only laboratory in the race: China announced in 2015 that it plans to start building the world’s largest particle accelerator by 2025.