Preface Finally we would like to thank our colleagues in the kavli institute of nanoscience at the Delft University of Technology and in the Dahlem Center for Complex Quantum Sys- mn understanding of everyone around us for this.J.D.would like to thank in particular Piet Brouwer and Dganit Meidan:they both were always willing to free some time for very helpful discussions about the content and style of the material in preparation. Yuli V.Nazarov Jeroen Danonxiv Preface Finally, we would like to thank our colleagues in the Kavli Institute of Nanoscience at the Delft University of Technology and in the Dahlem Center for Complex Quantum Sys￾tems at the Free University of Berlin. Especially in the last few months, our work on this book often interfered severely with our regular tasks, and we very much appreciate the understanding of everyone around us for this. J.D. would like to thank in particular Piet Brouwer and Dganit Meidan: they both were always willing to free some time for very helpful discussions about the content and style of the material in preparation. Yuli V. Nazarov Jeroen Danon