Two contributions on closely related subjects: the theory of linear algebraic groups and invariant theory, by well-known experts in the fields. The book will be very useful as a reference and research guide to graduate students and researchers in mathematics and theoretical physics.

From July 25-August 6, 1966 a Summer School on Local Fields was held in Driebergen (the Netherlands), organized by the Netherlands Universities Foundation for International Cooperation (NUFFIC) with financial support from NATO. The scientific organizing Committl!e consisted ofF. VANDER BLIJ, A. H. M. LEVELT, A. F. MaNNA, J. P. MuRRE and T. A. SPRINGER. The Summer School was attended by approximately 80 mathematicians from various countries. The contributions collected in the present book are all based on the talks given at the Summer School. It is hoped that the book will serve the same purpose as the Summer School: to provide an introduction to current research in Local Fields and related topics. July 1967 T. A. SPRINGER Contents ARnN, M. and B. MAZUR: Homotopy of Varieties in the Etale Topology 1 BAss, H: The Congruence Subgroup Problem 16 BRUHAT, F. et J. TITs: Groupes algebriques simples sur un corps local . 23 CASSELS, J. W. S. : Elliptic Curves over Local Fields 37 DwoRK, B. : On the Rationality of Zeta Functions and L-Series 40 MaNNA, A. F. : Linear Topological Spaces over Non-Archimedean Valued Fields . 56 NERON, A. : Modeles minimaux des espaces principaux homo genes sur les courbes elliptiques 66 RAYNAUD, M. : Passage au quotient par une relation d'equivalence plate . 78 REMMERT, R. : Algebraische Aspekte in der nichtarchimedischen Analysis . 86 SERRE, J. -P. : Sur les groupes de Galois attaches aux groupes p-divisibles . 118 SWINNERTON-DYER, P. : The Conjectures of Birch and Swinnerton- Dyer, and of Tate . 132 TATE, J. T.

Two contributions on closely related subjects: the theory of linear algebraic groups and invariant theory, by well-known experts in the fields. The book will be very useful as a reference and research guide to graduate students and researchers in mathematics and theoretical physics.

The first edition of this book presented the theory of linear algebraic groups over an algebraically closed field. The second edition, thoroughly revised and expanded, extends the theory over arbitrary fields, which are not necessarily algebraically closed. It thus represents a higher aim. As in the first edition, the book includes a self-contained treatment of the prerequisites from algebraic geometry and commutative algebra, as well as basic results on reductive groups. As a result, the first part of the book can well serve as a text for an introductory graduate course on linear algebraic groups.