So what’s next for high-energy physics? The LHC won’t be the end. Physicists will want to go to higher energies. The question is, how? The International Linear Collider — a planned linac that will do for positrons and electrons what the LHC did for protons — is what the community wants right now, but it won’t go to any higher energies. It might be too expensive to build just to match the LHC’s capabilities. Machines like the ILC struggle to achieve accelerating gradients of 30 MeV per metre, and the radio wave power delivered to the metallic cavities would melt them were they not supercooled and superconducting.