Why do the elements occur in the universe with their observed abundances? Observations of stellar spectra, combined with laboratory data on nuclear reactions, help to explain their synthesis.
Despite almost universal belief that particles cannot move faster than light, one can think of negative‐energy particles traveling backward in time whose speed exceeds that of light. Experimenters are looking for these faster‐than‐light particles.
With national committees from 37 countries directing its policy and activity, IUPAP fosters international meetings, spreads information and hopes to advance international understanding.