In recent years, the study of weak interaction and its relationship with the other fundamnetal interactions of nature has progressed rapidly. Weak interactions of leptons and quarks provides an up-to-date account of this continuing research. The Introduction discusses early models and historical developments in the understanding of the weak force. The authors then give a clear presentation of the modern theoretical basis of weak interactions, going on to discuss recent advances in the field. These include development of the eletroweak gauge theory, and the discovery of neutral currents and of a host of new particles. There is also a chapter devoted entirely to neutrino astrophysics. Its straightforward style and its emphasis on experimental results will make this book an excellent source for students (problem sets are included at the end of each chapter) and experimentalists in the field. Physicists whose speciality lies outside the study of elementary particle physics will also find it useful.

The book “Leptons and Quarks” was first published in the early 1980s, when the program of the experimental search for the intermediate bosons W and Z and Higgs boson H was formulated. The aim and scope of the present extended edition of the book, written after the experimental discovery of the Higgs boson in 2012, is to reflect the various stages of this 30+ years search. Along with the text of the first edition of “Leptons and Quarks” it contains extracts from a number of books published by World Scientific and an article from “On the concepts of vacuum and mass and the search for higgs” available from www.worldscientific.com/worldscinet/mpla or from arxiv.org/abs/1212.1031.The book is unique in communicating the Electroweak Theory at a basic level and in connecting the concept of Lorenz invariant mass with the concept of the Extended Standard Model, which includes gravitons as the carriers of gravitational interaction.

A graduate-level description of how the theory of electroweak interactions, or so-called "Standard Model" unifies the weak and electromagnetic forces of nature in high energy physics.

Matters are made of quarks and leptons. There are three families of them, each containing two quarks and two leptons. Ordinary matters are made of leptons and quarks of Family I. Quarks also come in three colours. The interaction of lepton and quarks are described by the Standard Theory, which is described by the gauge group SU(3) x SU(2) x U(1). It consists of the electromagnetic interaction mediated by the photon, the charged weak interaction mediated by the W+ bosons, the neutral weak interaction mediated by the Z boson and the strong interaction mediated byt he eight gluons.The charged weak interaction mixes quarks from different families. It is this mixing that gives rise to CP violation phenomena. [Author's abstract].