| The Standard Model (SM) of Particle Physics can sucessfully account for all known data at particle colliders, yet as a theoretical model it is incomplete. The instability of the Higgs particle to radiative corrections, the values of the quark and lepton masses and mixings, CP violation, and lack of unification of the forces including gravity all point to the SM being a low energy effective form of a more fundamental theory. Supersymmetry (SUSY) could be a valid replacement for the SM at energies over a few hundred GeV. The phenomenology of SUSY models includes many more particles, potential sources of CP violation, and flavor-changing processes which experiments under development can test. Similarly, the SM could be a low energy effective limit of a noncommutative geometry in which the coordinates of space-time do not commute: [] ≠ 0. In a noncommutative geometry new sources of CP violation may arise, as well as a host of direction-correlated signals at high energy colliders. A novel feature of noncommutative theories is the coupling of long and short distance dynamics. It may be simple to account for this phenomenon in a field theory defined on a discrete space-time. |
