Quantum Analogues: From Phase Transitions to Black Holes and Cosmology

Abstract

'And I cherish more than anything else the analogies, my most trustworthy masters. They know all the secrets of nature, and they ought to be least neglected in geometry.'These words of the great astronomer Johannes Kepler embody the philosophy behind the research recounted in this interesting book—a book composed of nine selected lectures (and a nice introduction by Bill Unruh) from the international workshop on 'Quantum Simulations via Analogues', which was held in the Max Planck Institute for the Physics of Complex Systems in Dresden during the summer of 2005.Analogue models of (and for) gravity have a long and distinguished history dating back to the earliest years of general relativity. However the last decade has seen a remarkable and steady development of analogue gravity models based on condensed matter systems, leading to some hundreds of published articles, numerous workshops, and several books. While the main driver for this booming field has definitely been the puzzling physics associated with quantum effects in black holes, more recently much attention has also been devoted to other interesting issues—such as cosmological particle production or the cosmological constant problem. Moreover, together with these new themes there has been a persistent interest in the possibility of simulating cosmic topological defects in the laboratory (although it should be said that momentum for this line of research has been somewhat weakened by the progressive decrease of interest in cosmological topological defects as an alternative to inflationary scenarios).All these aspects are faithfully accounted for in this book, which does a good job at presenting a vivid snapshot of many (if not quite all) of the most interesting lines of research in the field. All the articles have a self-consistent structure—which allows one to read them in arbitrary order and appreciate the full richness of each topic. However, when considered together I would say that they also provide a gentle hint of where the main 'research flow' is going (to use another analogy!). For example, it seems to me that it clearly puts into evidence some of the most prominent present-day trends—like the growing attention devoted to particularly 'malleable' systems like Bose–Einstein condensates (four over nine lectures are entirely or largely based on these striking condensed matter systems), as well as the remarkable degree of complexity achievable in 3He-based analogues.With the exception of the Schützhold article (which can be considered a nice introduction to the issue of horizon physics in analogue models), I would consider each of the articles to be a self consistent account of a particular line of research. In this sense, I think it should be made clear to a potential reader that this book does not propose itself as a systematic review of the entire field (there are already several monographs available online for this purpose) and one should not expect any explicit logic flow linking the various contributions. Rather I would say that this book should be seen as a very useful source of information for researchers with some knowledge of the field, readers who might be looking for several mini-reviews on some of the hot research issues (each of the articles often collects results from several papers of the authors).In conclusion, I think this book is definitely a worthwhile addition to any scientific library, and necessary reading for anybody interested in understanding present trends in analogue models of gravity.