Strangeness nuclear physics at JHF. YN and YY interaction

Understanding properties of hadrons, interactions of hadrons and forms of existence of the hadronic matter is the goal of the strong interaction physics. Most of the strong interaction of the QCD is, however, used out to confine quarks and gluons into hadrons and only a small portion comes out as interactions of hadrons. If JHF (Japan Hadron Facility) changes the environment such as finite temperature and/or density or implanting strangeness, the situation will be completely different. It is important to study YN and YY interactions together with the NN interaction as the problem of the interaction of two SU(3) baryons. In order to achieve a consistent picture of the strong interaction, strangeness, isospin, and spin dependence of the BB interaction must be understood. Three theories, namely, the lattice QCD, the QCD sum rule, and the effective field theory are discussed as the theoretical approaches to the BB interaction. It is hoped that JHF will provide with new experimental data for the YN and YY interactions and will explore yet unknown rich world of the hadron physics. Theoretically, little is understood for the three-flavor BB interaction and clearly there are many things that can be done and must done. (S. Funahashi)