Progress towards an understanding of the dynamics and interactions of galaxies has been spurred on more than ever by a wealth of new observations and numerical experiments. The Heidelberg Conference 1989, the papers of which are collected in this volume, was extremely successful in presenting a synoptic view of the field in all its aspects: galaxy interactions in the early universe and in recent times, interactions of our galaxy and its neighbours, dynamical problems of elliptical and disk galaxies, groups and clusters, starburst and nuclear activity triggered by interactions, merger scenarios, and numerical experiments. Researchers and graduate students, specialists or not, will find here a complete overview of a rapidly growing field of astronomy.

Bulges lie at the heart of most galaxies, the building blocks of our universe. With a selection of reviews and topical presentations, IAU Symposium 245 provides an up-to-date overview of our knowledge on galaxy bulges, and a concise introduction to all current research on the subject. The structure, dynamics, and stellar populations of galaxy bulges, both near and far, are analysed through state-of-the-art observations. The leading models for the formation and evolution of galaxy bulges are described in detail, and the constraints observations put on these are dissected. Particular emphasis is placed on exploring evidence for both hierarchical merging and secular processes. Special attention is also devoted to disentangling the complex web relating galaxy bulges and central supermassive black holes, and on the lessons learned from our exquisite knowledge of the bulge of our own Milky Way. This volume is the best one-stop reference on galaxy bulges currently available.

This volume contains the written versions of the lectures given at the 26th course of the renowned Saas-Fee series. The book represents a comprehensive and up-to-date review of the field of galaxy interaction. Nowadays, galaxies are no longer seen as immutable objects: they evolve, interact, merge, blaze, and reshape. Dynamic forces can induce powerful stellar activity able to transform the matter composition and morphology of galaxies. The lectures included in this book aim at a better understanding of these remarkable and fascinating phenomena. Though the book is intended for graduate students and young post-docs in astrophysics, it contains more advanced and original material, as well as historical perspectives, which will be of great interest to experts and astronomy teachers also.

These proceedings offer professional astronomers an overview of the rapidly advancing subject of galaxy interactions at low and high redshifts. The symposium gave participants an exciting glimpse of a developing synthesis highlighting galactic encounters and their role in the history of the Universe.

How gas flows and starbursts light up active galaxies.