In this volume seven leading theoreticians and experimenters review the origin of the asymmetry of matter and antimatter in the Big Bang, solar neutrinos, the physics of enormous densities and temperatures in stars and of immense magnetic fields around collapsed stars, strong electric fields in heavy ion collisions, and the extreme conditions in quark-gluon plasmas. The articles address nuclear and particle physicists, especially graduate students, but also astrophysicists and cosmologists, since they have to deal with events under the extreme physical conditions discussed here.