Abstract:
These lectures on 'Semigroups of Operators' are based on the lectures given by the Visiting Professor, A. T. Bharucha-Reid, with particular reference to applications in Mathematical Physics. The three operators - semigroup operators, infinitesimal operator of the semigroup(generator), resolver of the infinitesimal operator, their properties and the relationships between them are discussed in the chapters. Sections of chapters deal with "generation of semigroups of operators of Class(C0), in an arbitrary Banach Space", "generation of semigroups in Hilbert Space", and "uniqueness of the generation problem". Further Perturbation theory for semigroups of class (C0), is considered with an application to differential equations in Banach spaces. Equivalence of semigroups of operators, and their properties, an exposition of Sz.-Nagy's Representation theory of contraction semigroups in Hilbert Space are dealt with in some chapters. The chapter 'Semigroup methods in Mathematical Physics' devotes to semigroups in Quantum mechanics, semigroups with partial differential equations, and Use of Semigroup methods in obtaining the solutions of the Boltzmann equation of transport theory.