Unlock the Editor’s Digest for free

Physicists in Europe this week unveiled a €16bn bid to build the world’s costliest instrument dedicated purely to scientific inquiry. They plan a giant particle accelerator in a 91km ring beneath the Swiss-French borderlands, in which subatomic particles will collide almost at the speed of light. The project has crystallised a debate about whether so many billions should be ploughed into fundamental research or spent on more practical issues, such as pandemic readiness and climate change.

The Future Circular Collider proposed by the Cern laboratory near Geneva may seem like an extravagant demand on the governments that will have to pay for it, when so many other fields of research are desperately short of public funds. But an advanced society should be prepared to pay for endeavours to extend our knowledge of the universe, be they atom smashers or space observatories such as the (almost as costly) James Webb telescope.

Cern’s current 27km Large Hadron Collider was built with one primary aim: to produce and characterise the Higgs boson, a long-sought particle that gives mass to other components of the universe. The LHC achieved that triumphantly in 2012 and since then it has been advancing knowledge of subatomic physics without making headlines beyond the scientific press.

The FCC does not have such a well-defined mission. Quite what it might find is impossible to predict, though the energies of its subatomic collisions will be so much higher than any previously achieved on Earth that physicists are confident that their understanding of nature at the smallest scales will be enhanced. Possible discoveries include the nature of the mysterious dark matter and dark energy that dominate the universe. There may even be clues about how to reconcile the two overarching theories of physics: relativity and quantum mechanics.

If Cern’s 23 European member states agree to build the FCC once a feasibility review is completed next year, detailed planning, construction and commissioning will take at least two decades. The process will lead to practical advances in fields such as cryogenics, superconductivity, magnet technology and computing. As Cern likes to remind us, it gave birth to the World Wide Web in 1989 to enable data-sharing by scientists around the world.

But the promise of technological spin-offs is very much a secondary justification. The reason to invest in the FCC is to gain fundamental knowledge about the way the universe works. This will be rewarding in a cultural or philosophical sense. It may also pay off practically in the far future through applications we cannot foresee today — just as 21st-century technology in fields from computing to satellite navigation depends on an understanding of quantum theory and relativity, whose foundations were laid by pioneering physicists almost a century ago.

The FCC’s provisional price tag of €16bn includes building its subterranean ring, associated infrastructure and four experimental stations to track the myriad particles generated by subatomic collisions. Like any large capital investment, the budget may escalate well above original estimates — and running the experiments will cost billions of euros more — but costs will be spread over many years and shared by many countries. If the FCC goes ahead, it will consume only a tiny fraction of the world’s total spending on basic research, which exceeds $100bn a year.

Although the FCC will be a European-led endeavour, Cern will count on substantial contributions from elsewhere — particularly the US but also Japan, China, India and others. It should be seen as a global collaboration, much needed in a time of geopolitical turmoil, to understand better the universe in which we all live.   

Source link