high energy physics thinks that bigger colliders will let them find new particles, but this view is probably wrong.

You could build a circular machine 3x the size of the Large Hadron Collider to collide electrons and positrons; you could upgrade the LHC, or even build a next-generation linear accelerator. Probing higher energies offers the hope of new physics — it could be supersymmetry, it could be something else, I don’t know what. But before exploring higher energies, it makes sense to me to build a muon collider, and to clarify the question of the Higgs first. Here we already have a particle that we want to explore. We may even find signs of new physics by studying the Higgs very precisely. For that we don’t need to go to a 100-kilometer-around tunnel. Think about how many days it takes to walk 100 kilometers! And it all has to be extremely functional, every single piece has to work — it’s a miracle if people succeed in making it work.