The contributions in this conference proceeding present an alternative approach to solving the Quantum Field Theory problem using the variational approach. Many different issues are visited using this approach — Yang Mills Theory, going beyond the Guassian Approximation, in QCD and QED.
Quantum systems in all areas of physics, from atomic and molecular physics, nuclear and particle physics to condensed matter and astrophysics, provide a rich mosaic of different structures. Yet there are some simple and universal working principles of nature which seem to govern these structures and manifest themselves in various forms, as well as likely hypothetical ones which might do the same. For example, the same symmetry group structure occurs again and again in optics, atomic physics and particle physics. Concepts like potential, phases, bound states, tunneling, interference, solitons, radiation and resonance are universal.It is for those reasons that a collection of recent works in the many areas of physics on quantum structures and the methods for their investigation is important. The present volume fulfills this task to a large extent. The contributions are wide-ranging and yet there is a certain continuity. The main topics, namely non-perturbative methods in quantum theory, quantum nonlinear systems, quantum phases and magnetic monopoles, are covered by longer review articles and are enriched by many related contributions. It is also very appropriate that the corresponding mathematical methods, such as those for solving Schrödinger and relativistic wave equations, as well as those of algebra and group representations and analysis, are included in this volume.
This volume summarizes our contemporary understanding of the deconfinement transition in QCD at finite temperature and chemical potential. Questions as to whether a quark-gluon plasma exists in the interior of dense astrophysical objects or which bound-state signals have to be studied in order to unambiguously detect the QCD phase transition(s) in future heavy-ion collision programmes at RHIC and LHC are addressed. Progress in answering these questions requires a fusion of lattice QCD with other nonperturbative approaches and low-energy effective models for QCD. Experts in these fields present in the book their methods and their results in understanding the deconfinement phenomenon.
This book contains the invited contributions to the 6th International Conference on Path Integrals from peV to TeV, held in Florence in 1998. The conference, devoted to functional integration, brought together many physicists with interests ranging from elementary particles to nuclear, solid state, liquid state, polymer and complex systems physics. The variety of topics is reflected in the book, which is a unique collection of papers on manifold applications of functional methods in several areas of physics.
Quantum many-body theory as a discipline in its own right dates largely from the 1950's. It has developed since then to its current position as one of the cornerstones of modern theoretical physics. The field remains vibrant and active, vigorous and exciting. Its most powerful techniques are truly universal. They are constantly expanding to find new fields of application, while advances continue to be made in the more traditional areas. To commemorate the impending 80th birthdays of its two co-inventors, Firtz Coester and Hermann Kummel, one such technique, namely the coupled cluster method, was especially highlighted at this meeting, the eleventh in the series of International Conferences on Recent Progress in Many-Body Theories. The history of the coupled cluster method as told here mirrors in many ways both the development of the entire discipline of microscopic quantum many-body theory and the history of the series of conferences. The series itself is universally recognised as being the premier series of meetings in this subject area. Its proceedings have always summarised the current state of the art through the lectures of its leading practitioners. The present volume is no exception. No serious researcher in quantum many-body theory or in any field which uses it can afford to be without this volume.
This proceedings volume contains selected talks and poster presentations from the 9th International Conference on Path Integrals OCo New Trends and Perspectives, which took place at the Max Planck Institute for the Physics of Complex Systems in Dresden, Germany, during the period September 23OCo28, 2007. Continuing the well-developed tradition of the conference series, the present status of both the different techniques of path integral calculations and their diverse applications to many fields of physics and chemistry is reviewed. This is reflected in the main topics in this volume, which range from more traditional fields such as general quantum physics and quantum or statistical field theory through technical aspects like Monte Carlo simulations to more modern applications in the realm of quantum gravity and astrophysics, condensed matter physics with topical subjects such as BoseOCoEinstein condensation or quantum wires, biophysics and econophysics. All articles are successfully tied together by the common method of path integration; as a result, special methodological advancements in one topic could be transferred to other topics."