Research in theoretical elementary particle physics will include analyses of possible Higgs particle signals at future colliders, studies of the interactions between photons and neutrinos in situations of astrophysical interest, and investigations of the utility and validity of `effective field theories` intended for the simplified treatment of low-energy reactions. The Higgs particles are related to the genesis of mass, and their number, as well as their relative masses and charges, must be determined in order to fully understand the origin of mass and the underlying symmetry of elementary particle theory. Photons and neutrinos only interact appreciably under extreme conditions such as those found in the early universe or in compact astrophysical objects. It is important to determine if this interaction alters our view of such things as the relic neutrinos in cosmology or the way in which heavy objects loose energy. Since effective field theories provide a convenient description of the low energy behavior of many processes, it is essential to check them against exact theories which are accurate at all energies.
