In recent years the Standard Model of electroweak interactions has successfully passed a number of crucial tests, most notably in neutral current reactions and through the observation of W- and Z-bosons in proton-antiproton collisions. How ever, experiments are only beginning to verify one of the most basic consequences of its theoretical formulation as a local quantum field theory: quantum corrections as calculated in perturbation theory. Measurements that will be carried out at electron positron colliders at Stanford and CERN in the very near future will improve the accuracy by more than an order of magnitude. Thus either these crucial elements of the present theoretical framework will be confirmed or the road to physics beyond the Standard Model will be opened. A huge amount of theoretical work has been invested during the past few years to match the envisaged experimental precision. QED corrections, in particular from initial state radiation, will playa dominant role in the interpretation of measurements and have to be understood at a hitherto unrivalled level of accuracy. Analytical cal culations - either to a fixed order in a or by summing large logarithms to arbitrary order - are complementary to recent developments of Monte Carlo techniques in the simulation of events with multiple photon emission. Measurements with hadronic final states evidently require the understanding of hadronic corrections to high accu racy. Even purely leptonic reactions are influenced by hadronic interactions through vacuum polarization.

The Workshop on Radiative Corrections: Results and Perspectives was held at the University of Sussex in fine weather between July 9 and 14 1989. The Workshop was weIl timed: the day after its concluding session the first beam at LEP was circulated. The Original aims of the Workshop were twofold: first to review the existing theoretical work on electroweak radiative corrections in the light of the initial experiments at SLC and LEP, and to attempt to obtain a consensus on the best means of carrying out the calculations of the various processes. This aim became Working Group A on Renormalisation Schemes tor Electroweak Radiative Corrections. The second aim was to review the experimental implementation of radiative corrections and this became Working Group B. Here the problem was to obtain a consensus on the use of Monte Carlo event generators. At the time (March 1987) when Friedrich Dydak wrote to one of us (ND) to suggest a Workshop on the subject of electroweak radiative corrections to take place just before experiments at LEP were to begin, the main theoretical problem was that there was no agreement among theorists on the use of a specific renormalization scheme. Similarly, it was already becoming clear that it was going to be very difficult to compare the experimental results of different groups because they would use different event generators and experimental cuts of their data.

The field of particle physics is developing very rapidly. During this past year, physicists added a new instrument to their arsenal for the study of quark-quark, quark-lepton, and lepton lepton interactions. This machine, the PROTON-ANTIPROTON COLLIDER, achieved the highest energy in the world. With its five detectors, it is beginning to explore hitherto inaccessible regions for new physics (Section I). Lepton-Iepto~ machines with detectors at full efficiency are producing copious data of the very highest precision. The possibility of glueballs and the detailing of the properties of the upsilon family have been of major importance this year (Section II). The particle jets which are believed to be direct manifesta tions of the quark structure of matter continue to provide valuable data against which we can test the ideas of QCD (Section III). With the advent of more and better data it is now possible to study in detail the formation evolution of hadronic states. Especially interesting are the properties of heavy quark states (Section IV). A far-seeing look into the future development of any fecund scienti fic field is rarely accurate, but is always stimulating (Section V). It is against this background of participating in the clarifi cation of the Physics in Collision that we continue this series.

The XIX Physics in Collision conference reviewed experimental results in electroweak, quantum chromodynamics, neutrino, bottom and rare kaon physics, and updated recent developments in the area of gamma ray bursts as well as the issue of the cosmological constant and dark matter.The conference opened with reports on electroweak physics. A decade of precision experiments in laboratories around the world failed to uncover any significant deviations from standard model predictions. Precise W boson and top quark mass measurements suggest a low mass Higgs boson in the standard model, possibly within the reach of the LEP II and the upgraded Tevatron colliders. These presentations were followed by a summary of the latest results on searches for Higgs and supersymmetry.There were three reports on neutrino physics: atmospheric, solar and reactor/accelerator based neutrino experiments and results. Impressive Super-K results strongly suggest ????? oscillation, a scenario confirmed by less precise Soudan2 and MACRO data.The latest results on strange and heavy quark physics were summarized. High statistics from CLEO, LEP I and Tevatron have enabled experimenters to study many rare charm and bottom quark decays for the first time. Among many other interesting results presented, the first measurements of sin 2? by CDF and î?/î by KTeV provide a preview of expected developments in the near future.

Following on from the successful first (1984) and revised (1993) editions, this extended and revised text is designed as a short and simple introduction to quantum field theory for final year physics students and for postgraduate students beginning research in theoretical and experimental particle physics. The three main objectives of the book are to: Explain the basic physics and formalism of quantum field theory To make the reader proficient in theory calculations using Feynman diagrams To introduce the reader to gauge theories, which play a central role in elementary particle physics. Thus, the first ten chapters deal with QED in the canonical formalism, and are little changed from the first edition. A brief introduction to gauge theories (Chapter 11) is then followed by two sections, which may be read independently of each other. They cover QCD and related topics (Chapters 12-15) and the unified electroweak theory (Chapters 16 - 19) respectively. Problems are provided at the end of each chapter. New to this edition: Five new chapters, giving an introduction to quantum chromodynamics and the methods used to understand it: in particular, path integrals and the renormalization group. The treatment of electroweak interactions has been revised and updated to take account of more recent experiments.