Future Collider Update | Not Even Wrong

Various news about a possible future collider, all pointing to the CERN FCC-ee as the leading proposal.

• For up to date background technical information on proposed colliders, including cost estimates, see here.
• The Chinese CEPC plan is now on hold, as a decision was reached to not include it in China’s plans for the next five years (2026-30).
• As part of the European Strategy for Particle Physics update process, recommendations drafted earlier this month have now been released (see here and here). As expected, the main recommendation is to pursue the FCC-ee project, which will cost an estimated \$18 billion dollars or so. The fall-back recommendation in case this is too expensive is rather odd. People were expecting such a fall-back to be some sort of linear collider, which would cost half as much. Instead the fall-back recommendation was for essentially the same FCC-ee project, saving just 15% with various cuts to its capabilities. There’s a reaction to this from the linear collider people here.
• CERN today announced that private donors have pledged \$1 billion towards the FCC-ee project.

CERN will not make a final decision on this until 2028. I’ve always been skeptical that there is a viable financial path to funding a \$15 – \$20 billion new collider. Perhaps in our new world order where everything is controlled by trillionaire tech bros, the financing won’t be a problem.