The aim of Letters in Mathematical Physics is to present to the specialised reader (from the level of graduate student upwards) important new developments in the area of mathematical physics. The journal is a vehicle for the rapid communication of short contributions and contains letters and occasionally short review articles and research projects in the fields of: modern group theory and applications to physics; quantum-field theory; mathematical models for physical systems; classical quantum and statistical mechanics; relativity and gravitation etc. It contains in addition important contributions to modern mathematics in such fields as functional analysis differential geometry algebra topology etc. which have a potential physical application and important developments in theoretical physics which have potential mathematical impact.