Condensed Matter Theories

This the first volume of the proceedings of the International Workshop on Condensed Matter Theories published by a commercial publisher and of a series which is planned to appear anually. It is a tribute to the group of scientists who started this workshop as the Pan American Workshop on Conden­ sed Matter Theories in 1977 and helped to develop it to a significant annual international workshop. Many scientists' efforts have contributed to this important development and it is impossible to name all of them. But at least three persons are to be singled out: Professors Manuel de Llano and Angel Plastino who conceived the idea of the annual workshop and carried it for­ ward, and Professor John W. Clark who has been the prime driving force be­ hind it in recent years. The Workshop started in 1977 in Sao Paolo, Brazil, as the first Pan American Workshop on Condensed Matter Theories with the idea of bringing together scientists from the Western Hemisphere working in many different areas of Condensed Matter Theories for the purpose of cross-fertilization of ideas used in different areas and fostering collaborations among them. The next five Workshops were held at Trieste, Italy, in 1978; in Buenos Aires, Argentina, in 1979; in Caracas, Venezuela, in 1980; in Mexico City, Mexico, in 1981; and in St. Louis, Missouri, U. S. A. , in 1982.