A new particle accelerator four times larger than the Large Hadron Collider is about to move a step closer, as CERN is poised to support the €20 billion (£18bn) project.
The Future Circle Collider (FCC) will have a 62 mile (100km) circumference and be six times more powerful than the Large Hadron Collider (LHC).
The FCC will allow particle scientists to study the Higgs boson in more detail, look for other particles, and could also provide new insight into dark matter.
Even if CERN backs the project, it would still need to secure funding from EU members states, the UK and other interested parties before construction can start.
If the €20 billion it will cost to build is secured, it won’t be operational until the 2040s, as work won’t start for about a decade and it will take just as long to build.
The Future Circle Collider (FCC) was first proposed back in 2017 and will have a 62 mile (100km) circumference and be six times more powerful than the LHC.
The FCC will allow particle scientists to study the Higgs boson in more detail, look for other particles and it could provide an insight into dark matter
It’s not just a case of securing the initial construction investment either; countries funding the project will have to commit to paying for operations into the 2050s.
Officials hope for a decision by CERN’s 22 member states within the next few years about the project, that would debut with an electron-positron collider at an estimated cost of €9billion.
A second phase would involve a superconducting proton machine in the same tunnel – bringing the total cost to about €20 billion.
While the first machine would start operations in the 2040s, the second machine could start smashing particles sometime in the late 2050s.
‘The FCC’s ultimate goal is to provide a 100-kilometre superconducting proton accelerator ring, with an energy of up to 100 TeV, meaning an order of magnitude more powerful than the LHC,’ said Frédérick Bordry from CERN.
‘The FCC timeline foresees starting with an electron-positron machine, just as LEP preceded the LHC,’ he said.
Expanding our understanding of the fundamental laws of nature requires the energy frontier to be pushed much further, CERN researchers said of the new collider.
‘Reaching this goal within the 21st century in an economic and energy efficient way calls for a large circular collider,’ they wrote.
The first stage after approval is given and funding secured will be to conduct a geological survey to see if there are any underground lacks beneath Geneva.
If there are it could lead to the whole plan – and location of the FCC to be reconsidered, which could delay its operational launch.
In fact some of the technology required to smash particles at the sort of energy level being proposed doesn’t exist yet.
Research is needed into high-field superconducting magnets and other technologies before construction of the actual collider can begin.
This was one of a number of projects proposed as a replacement for the LHC when it reaches the end of its life by the start of the next decade.
Another proposal was a linear collider which could have been expanded in stages, but the FCC was chosen instead due to the ability to run multiple experiments in the same tunnels.
Not only will the machine be larger, but it will be equipped with double strength magnets for more powerful collisions.
This could ultimately help to solve many of the universe’s unanswered mysteries, including dark matter.
‘When you look into things like the movement of galaxies, we see that we can only understand and explain about 5 percent of what we observe,’ Professor Michael Benedikt, leader of the FCC, told Horizon Magazine.
‘But with questions like the so-called problem of dark matter, which is linked to the fact that galaxies and stars are not moving as you would expect them to, the only explanation we have is that there must be matter we do not see which distorts the movement accordingly.’
CERN says the machine will be a kind of ‘Higgs factory’ – producing enough of the bosons – first discovered at the LHC in 2012 – to give scientists a deeper insight.
Artistic view of a collision event at the FCC. Expanding our understanding of the fundamental laws of nature requires the energy frontier to be pushed much further, CERN researchers said of the new collider
Artistic impression of the FCC accelerator and tunnel. Not only will the machine be larger, but it will be equipped with double strength magnets for more powerful collisions
‘The discovery of the Higgs boson was a milestone in the long-standing effort to complete the Standard Model of Particle Physics,’ the agency wrote.
‘Yet the Standard Model cannot explain certain observations, such as: the abundance of matter over antimatter, the striking evidence for dark matter and the non-zero neutrino masses.’
It’s hoped by producing them in greater numbers that experts will be able to understand how they decay – something not possible with the lower powered LHC.
This is important as it would allow CERN to discover if a leading theory – that Higgs particles decay into dark matter particles – is accurate or not.
‘The frontier machines envisaged by the FCC study offer a rich experimental programme spanning almost a century,’ CERN said int he design report.
Artistic view of the tunnel in the Franco-Geneva region. If the €20 billion it will cost to build is secured, it won’t be operational until the 2040s as work won’t start for about a decade and it will take just as long to build
An illustration of the layout of the FCC including locations of tunnels and experiments
‘The unprecedented precision and high energy reach, will extend well beyond the LHC our search for answers to the most fundamental questions.’
Not everyone is convinced that the FCC is a good investment, with suggestions the money could be better used for more directed research.
‘There is no reason to think that there should be new physics in the energy regime that such a collider would reach,’ says Sabine Hossenfelder, a theoretical physicist at the Frankfurt Institute for Advanced Studies in Germany.
‘That’s the nightmare that everyone has on their mind but doesn’t want to speak about,’ she told Nature.
She said other large projects would also be a better use of the money including a radio telescope on the far side of the Moon or a gravitational wave detector in orbit.
CERN said it was not possible to say exactly what benefits the new collider would bring to the world, but pointed out that the discovery of the electron in 1897 led to the electronics industry.
‘Proton colliders have been the tool-of-choice for generations to venture new physics at the smallest scale,’ said Eckhard Elsen from CERN.
‘A large proton collider would present a leap forward in this exploration and decisively extend the physics programme beyond results provided by the LHC and a possible electron-positron collider.’