Hilbert Space, Boundary Value Problems and Orthogo. Questo articolo non è disponibile.Hilbert Space, Boundary Value Problems and Orthogo

The following tract is divided into three parts: Hilbert spaces and their (bounded and unbounded) self-adjoint operators, linear Hamiltonian systemsand their scalar counterparts and their application to orthogonal polynomials. In a sense, this is an updating of E. C. Titchmarsh's classic Eigenfunction Expansions. My interest in these areas began in 1960-61, when, as a graduate student, I was introduced by my advisors E. J. McShane and Marvin Rosenblum to the ideas of Hilbert space. The next year I was given a problem by Marvin Rosenblum that involved a differential operator with an "integral" boundary condition. That same year I attended a class given by the Physics Department in which the lecturer discussed the theory of Schwarz distributions and Titchmarsh's theory of singular Sturm-Liouville boundary value problems. I think a Professor Smith was the in­ structor, but memory fails. Nonetheless, I am deeply indebted to him, because, as we shall see, these topics are fundamental to what follows. I am also deeply indebted to others. First F. V. Atkinson stands as a giant in the field. W. N. Everitt does likewise. These two were very encouraging to me during my younger (and later) years. They did things "right." It was a revelation to read the book and papers by Professor Atkinson and the many fine fundamen­ tal papers by Professor Everitt. They are held in highest esteem, and are given profound thanks.

1.- I Hilbert Spaces.- II Bounded Linear Operators on a Hilbert Space.- III Unbounded Linear Operators on a Hilbert Space.- 2.- IV Regular Linear Hamiltonian Systems.- V Atkinson’s Theory for Singular Hamiltonian Systems of Even Dimension.- VI The Niessen Approach to Singular Hamiltonian Systems.- VII Hinton and Shaw’s Extension of Weyl’s M(?) Theory to Systems.- VIII Hinton and Shaw’s Extension with Two Singular Points.- IX The M (?) Surface.- X The Spectral Resolution for Linear Hamiltonian Systems with One Singular Point.- XI The Spectral Resolution for Linear Hamiltonian Systems with Two Singular Points.- XII Distributions.- 3.- XIII Orthogonal Polynomials.- XIV Orthogonal Polynomials Satisfying Second Order Differential Equations.- XV Orthogonal Polynomials Satisfying Fourth Order Differential Equations.- XVI Orthogonal Polynomials Satisfying Sixth Order Differential Equations.- XVII Orthogonal Polynomials Satisfying Higher Order Differential Equations.- XVIII Differential Operators in Sobolev Spaces.- XIX Examples of Sobolev Differential Operators.- XX The Legendre-Type Polynomials and the Laguerre-Type Polynomials in a Sobolev Spaces.- Closing Remarks.