Gregory Potel Aguilar obtained his Ph.D. at the University of Sevilla, Spain, in 2005. His work concerning the reaction mechanism of Cooper pair transfer in the study of pairing in atomic nuclei led him to earn a FRIB Theory Fellowship at the Facility for Rare Isotopes Beams (FRIB), Michigan. He is currently a staff scientist at the Lawrence Livermore National Laboratory. Ricardo A. Broglia earned his Ph.D. at the Institute J. Balseiro, University of Cuyo, Argentina, in 1965. Following positions at the University of Buenos Aires, the Niels Bohr Institute and the University of Minnesota, he joined the staff of the Niels Bohr Institute in 1970, where he is now an affiliated Professor. In 1985 he was called to occupy the Chair of Nuclear Structure at the University of Milan, a position at which he stayed until 2009. He is known for helping to develop the nuclear field theory based on Feynman's version of quantum electrodynamics and the theory of heavy ion reactions. His previous books include Oscillations in Finite Quantum Systems with George Bertsch and Nuclear Superfluidity with David Brink, which can be considered companions to the present volume.