Basics of Quantum Mechanics

Abstract

Quantum mechanics is the theory used to describe the physical objects of the “microscopic world” that are molecules, atoms, elementary particles such as electrons and photons. Classical mechanics based on the Newton's principles of dynamics and the classical electromagnetism based on Maxwell's equations do not work to describe microscopic physical systems. For instance, the classical electromagnetism does not provide the stability of the hydrogen atom that can be explained only in terms of its quantum description. In this chapter, we start from a list of general properties of the quantum physical systems that have been deduced as phenomenological evidences in quantum experiments. Next, we introduce the machinery of linear operators on Hilbert spaces to formalize the description of quantum systems.