# Lambda: A Mathematica package for operator product expansions in vertex algebras

## Description

This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018) Abstract We give an introduction to the Mathematica package Lambda, designed for calculating λ-brackets in both vertex algebras, and in SUSY vertex algebras. This is equivalent to calculating operator product expansions in two-dimensional conformal field theory. The syntax of λ-brackets is reviewed, and some simple examples are shown, both in component notation, and in N = 1 superfield notation. Title of program: Lambda Catalogue Id: AEHF_v1_0 Nature of problem Calculate operator product expansions (OPEs) of composite fields in 2d conformal field theory. Versions of this program held in the CPC repository in Mendeley Data AEHF_v1_0; Lambda; 10.1016/j.cpc.2010.09.018