From QCD Instantons at HERA to Electroweak B + L Violation at VLHC∗

This review emphasizes the close analogy between hard QCD instantoninduced chirality violating processes in deep-inelastic scattering and electroweak instanton-induced baryon plus lepton number (B + L) violating processes in Quantum Flavor Dynamics (QFD). Recent information about QCD instantons, both from lattice simulations and from the H1 experiment at HERA, can be used to learn about the fate of electroweak B +L violation at future high energy colliders in the hundreds of TeV regime, such as the projected Very Large Hadron Collider (VLHC). The cross-sections turn out to be unobservably small in a conservative fiducial kinematical region inferred from the above mentioned QCD–QFD analogy. An extrapolation – still compatible with lattice results and HERA – beyond this conservative limit indicates possible observability at VLHC. ∗Invited talk presented at the 26th Johns Hopkins Workshop on Current Problems in Particle Theory, August 1-3, 2002, Heidelberg, Germany.