A. Dold Books

Book by Stammbach, Urs

This volume consists of papers presented to the Second International Conference on the Theory of Groups held in Canberra in August 1973 together with areport by the chairman of the Organizing Committee and a collection of problems. The manuscripts were typed by Mrs Geary, the bulk of the bibliographie work was done by Mrs Pinkerton, and a number of colleagues helped with proof-reading; Professor Neumann, Drs Cossey, Kovacs, MeDougall, Praeger, Pride, Rangaswamy and Stewart. I here reeord my thanks to all these people for their lightening of the editorial burden. M. F. Newrnan CONTENTS 1 Introduction . . 8 yan, Periodic groups of odd exponent Reinhold Baer, Einbettungseigenschaften von der Schluss vom 13 Endlichen aufs Unendliche D. W. Barnes, Characterisation of the groups with the Gaschütz cohomology property 63 Gi Ibert Baumslag, Finitely presented metabe1ian groups 65 Gi Ibert Baumslag, Some problems on one-relator groups 75 A. J. Ba, J. Kautsky and J. W. Wamsley, Computation in nilpotent groups (application) 82 Wi I I iam W. Boone, Between logic and group theory 90 Richard Brauer, On the structure of blocks of characters of finite groups 103 A. M. Brunner, Transitivity-systems of certain one-relator groups 131 Egg8r M. Bryant, Characteristic subgroups of free groups 141 y, Metabe1ian varieties of groups 150 R. A. Bryce and John Cossey, Subdirect product c10sed Fitting c1asses 158 R. G.

Classification of commuting non-selfadjoint operators is one of the most challenging problems in operator theory even in the finite-dimensional case. The spectral analysis of dissipative operators has led to a series of deep results in the framework of unitary dilations and characteristic operator functions. It has turned out that the theory has to be based on analytic functions on algebraic manifolds and not on functions of several independent variables as was previously believed. This follows from the generalized Cayley-Hamilton Theorem, due to "Two commuting operators with finite dimensional imaginary parts are connected in the generic case, by a certain algebraic equation whose degree does not exceed the dimension of the sum of the ranges of imaginary parts." Such investigations have been carried out in two directions. One of them, presented by L.L.Waksman, is related to semigroups of projections of multiplication operators on Riemann surfaces. Another direction, which is presented here by M.S.Livsic is based on operator colligations and collective motions of systems. Every given wave equation can be obtained as an external manifestation of collective motions. The algebraic equation mentioned above is the corresponding dispersion law of the input-output waves.