Vertex Algebras and Commutative Algebras

Abstract

This paper begins with a brief survey of the period prior to and soon after the creation of the theory of vertex operator algebras (VOAs). This survey is intended to highlight some of the important developments leading to the creation of VOA theory. The paper then proceeds to describe progress made in the field of VOAs in the last 15 years which is based on fruitful analogies and connections between VOAs and commutative algebras. First, there are several functors from VOAs to commutative algebras that allow methods from commutative algebra to be used to solve VOA problems. To illustrate this, we present a method for describing orbifolds and cosets using methods of classical invariant theory. This was essential in the recent solution of a conjecture of Gaiotto and Rap\v{c}\'ak that is of current interest in physics. We also recast some old conjectures in the subject in terms of commutative algebra and give some generalizations of these conjectures. We also give an overview of the theory of topological VOAs (TVOAs), with applications to BRST cohomology theory and conformal string theory, based on work in the 90's. We construct a functor from TVOAs to Batalin-Vilkovisky algebras -- supercommutative algebras equipped with a certain odd Poisson structure realized by a second order differential operator -- and present a number of interesting applications. This paper is based in part on the lecture given by the first author at the Harvard CMSA Math-Science Literature Lecture Series on May 22, 2020.