Book 1413

Based on lectures delivered to the Seminar on Operator Algebras at Oakland University during the Winter semesters of 1985 and 1986, these notes are a detailed exposition of recent work of A. Connes and U. Haagerup which together constitute a proof that all injective factors of type III1 which act on a separable Hilbert space are isomorphic. This result disposes of the final open case in the classification of the separably acting injective factors, and is one of the outstanding recent achievements in the theory of operator algebras. The notes will be of considerable interest to specialists in operator algebras, operator theory and workers in allied areas such as quantum statistical mechanics and the theory of group representations.

Book 2171

This book offers an account of the classical theory of quadratic residues and non-residues with the goal of using that theory as a lens through which to view the development of some of the fundamental methods employed in modern elementary, algebraic, and analytic number theory.

The first three chapters present some basic facts and the history of quadratic residues and non-residues and discuss various proofs of the Law of Quadratic Reciprosity in depth, with an emphasis on the six proofs that Gauss published. The remaining seven chapters explore some interesting applications of the Law of Quadratic Reciprocity, prove some results concerning the distribution and arithmetic structure of quadratic residues and non-residues, provide a detailed proof of Dirichlet's Class-Number Formula, and discuss the question of whether quadratic residues are randomly distributed. The text is a valuable resource for graduate and advanced undergraduate students as well as for mathematicians interested in number theory.