Introduction to Hilbert Space and the Theory of Spectral Multiplicity

This concise introductory treatment consists of three chapters: The Geometry of Hilbert Space, The Algebra of Operators, and The Analysis of Spectral Measures. A background in measure theory is the sole prerequisite. "An exposition which is always fresh, proofs which are sophisticated, and a choice of subject matter which is certainly timely." — Bulletin of the American Mathematical Society.