This volume is a collection of lectures given during the 42nd Course of the International School of Subnuclear Physics. The contributions cover the most recent advances in theoretical physics and the latest results from current experimental facilities.In line with one of the aims of the school, which is to encourage and promote young physicists to achieve recognition at an international level, the students' recognized for their research excellence were given the opportunity to publish their work in this volume. Their contributions are joined by those from many distinguished lecturers in the field from around the world.