  Vertex algebras provide an axiomatic algebraic description of the operator
product expansion (OPE) of chiral fields in 2-dimensional conformal field
theory. Vertex Lie algebras (= Lie conformal algebras) encode the singular part
of the OPE, or, equivalently, the commutators of chiral fields. We discuss
generalizations of vertex algebras and vertex Lie algebras, which are relevant
for higher-dimensional quantum field theory.
