In automated negotiation systems consisting of self-interested agents, contracts have traditionally been binding. Such contracts do not allow agents to e ciently accommodate future events. Game theory has proposed contingency contracts to solve this problem. Among computational agents, contingency contracts are often impractical due to large numbers of interdependent and unanticipated future ev...

The present status of the problem of neutrino mass, mixing and neutrino oscillations is briefly summarized. The evidence for oscillations of atmospheric neutrinos found recently in the Super-Kamiokande experiment is discussed together with the results of the solar neutrino experiments and the accelerator LSND experiment.