Festkolloquium anlässlich des 85. Geburtstags von Prof. Dr. Herbert Daniel

The construction of ever larger and costlier accelerator facilities cannot continue forever,  and new technologies will be needed to push the energy frontier.  Two possible avenues for the future will be discussed: a novel acceleration technique based on plasma wake fields, and colliding muons rather than electrons. Plasma wakefield acceleration is a rapidly developing  field and the current status and experimental plans will be discussed. As for muon colliders - muons have the advantages of electrons in that they have no substructure, while the heavier mass suppresses synchrotron radiation such that high energies can be reached in a circular accelerator. However, muons are unstable and decay in two microseconds, such that novel techniques are needed to use them effectively in a particle collider.