A couple of developments toward the future of FCC

Over the past few months, despite my sporadic presence on these pages, I’ve been reporting in bits and pieces on the work done for the update of the European Strategy for Particle Physics. I had, for instance, written about it during the French symposium, which was expected to lead to the drafting of a national document, similar to those produced by other European countries for the occasion: all the inputs submitted during the process are available here for anyone interested in reading them. Summarizing everything has not been (and will not be) an easy task, but part of the work has already been carried out—initially during the Venice symposium last June, and especially with the publication of the Physics Briefing Book released in early November.

I cannot summarise the contents of the Physics Briefing Book here, but I can at least highlight a few key points. All studies seem to agree that, for the future goals of particle physics, the next major project after the LHC should be an electron–positron collider, and that FCC-ee—the collider that would be installed in a roughly 90-kilometre tunnel in the Geneva area—should be the preferred machine. The integrated FCC programme, in which FCC-hh (a very high–energy proton–proton collider in the same tunnel, much like LHC followed LEP) would succeed FCC-ee, is what would best secure the future of CERN and Europe’s central role in particle physics.

The next step after the publication of the Physics Briefing Book is to draft the strategy recommendations, a sort of concise and actionable version of the conclusions reached by the European particle physics community. The European Strategy Group is working on them right now, during a meeting at Monte Verità, in Ascona, Switzerland. The recommendations will be delivered to the CERN Council—the “parliament” overseeing the laboratory’s direction—which will then have to take concrete decisions for the coming years, also reflecting the political views of the nations funding CERN. The Monte Verità meeting will end this Friday, and we should then find out how science will have managed to become political message.

In the meantime, I’d like to highlight two recent developments that may have an important impact on the process. Let’s begin with the conclusions of the CERN Council meeting held in early November, which include a few interesting—albeit very cautious—statements. In particular, this one:

FCC would provide the platform for a visionary physics programme addressing many of the open questions in particle physics, notably on the Higgs boson, that are critical to understanding the foundations of the Standard Model and to opening up opportunities for discovering new physics beyond the Standard Model, while at the same time driving the development of new technologies that will have a significant positive impact on society.

The document contains a thousand economic and social caveats, but that statement above seems important to me, and points in what I believe is the right direction.

More or less at the same time, news arrived that CEPC, FCC’s potential Chinese competitor, has not been included in the 2026–2030 Chinese five-year plan. I’m not in a position to analyse all the reasons—especially the political ones—why our Chinese colleagues were unable to get CEPC approved as a concrete project for the next five years. But the fact remains that what, until a few weeks ago, looked like a potential threat to FCC (nobody seriously imagines two major electron–positron colliders operating simultaneously in two parts of the world: the next machine will be a global machine, or it won’t happen) is now, if not gone, at least postponed. This opens a five-year window for Europe to make decisions and regain the lead. CERN’s decision on whether to build FCC is expected by 2028: we still have time, and we should try to be bold and visionary.