Research in theoretical physics will concern the physics of elementary particles and other topics. Included will be novel mathematical approaches to string theory, studies aimed at selection of the "true" string theory from among many candidates, research on the physics of black holes, work on superfluidity, efforts to understand the origin of the masses of quarks and electron- like particles, and studies of quantum chromodynamics. String theories are promising candidates for a theory of all the basic forces, including gravity. The origin of the masses of the quarks and related particles is one of the outstanding problems in physics. Quantum chromodynamics is the (not-too-well-understood) theory of the strong nuclear force.
