Peter West is a theoretical physicist who is a pioneer of the theory of supersymmetry and its application to the construction of unified theories of all the fundamental particle interactions. Supersymmetry relates the properties of particles of different spin, which are divided into fermions and bosons, and it predicts that for every particle there should exist a specific particle of a different spin, called a superpartner.

His work on the quantum properties of supersymmetric theories in four dimensions and their coupling to gravity underlies how supersymmetry may yet be found in experiments conducted in particle accelerators.

Peter has also constructed supergravity theories in ten dimensions. These theories combine supersymmetry with general relativity, and they encode many of the properties of strings and branes. His results have become cornerstones of the modern theory of superstrings and associated branes.