| Citation | He is distinguished for many contributions to various branches of algebra by combining general methods from logic, especially recursion theory and model theory, with detailed studies of the specific branch involved; including logical methods originally developed for such isolated topics as models of high cardinality. Particularly noteworthy are his discoveries of logical definability and uniformity properties (for properly chosen languages) of p-adic fields, used recently in the (rationality) theory of p-adic Poincare series. He is also one of the founders of the currently lively subject of exponential rings, in which some early ideas of G.H. Hardy have found a proper home. |