This project uses the procedure of root-finding to resolve the eigenvalue problem of a rectangular quantum well. The procedure is applied to determine the first two to three energy levels of a simplified model of a hydrogen atom, represented by the rectangular quantum well. The project also explores the eigenvalue problem within various physics fields. While the project involves simple mathematical operations, it is rooted in complex physical concepts like quantum mechanics, often unfamiliar to first-year students. The fundamentals of quantum mechanics are introduced, providing enough understanding for successful project execution. The project initially focuses on the central object, the quantum state, and its probabilistic nature in quantum mechanics. The Schrödinger equation, an eigenvalue problem, is used to find state functions. This project explores eigenenergies and eigenfunctions within a rectangular finite quantum well, treating the well as a simplistic 1D model of the hydrogen atom.

The eigenvalues and eigenfunctions of self-adjoint differential operators provide the basis functions with respect to which ordinary and partial differential equations can be solved.These methods are extensions of those used to solve linear systems of algebraic equations and ordinary differential equations.Eigenfunction expansions also provide the basis for advanced numerical methods, such as spectral methods, and data-reduction techniques, such as proper-orthogonal decomposition.

This chapter introduces the Sobolev spaces and self-adjointellipticoperators on those spaces that will be used through the book. It also introduces basic concepts and tools such as Gelfand triples, the Sobolev embedding theorem, the equivalence between energy norm and the Sobolev space norm, the dual norm, the Green's function, and eigenfunctions.