THE ROLE OF ANTIFIELDS IN BRST THEORY

Antifields were originally introduced by Zinn-Justin in his seminal wo rk on the renormalization of gauge theories, as sources coupled to the BRST variations of the fields. This was motivated by the desire to co ntrol how the non-linear BRST symmetry passes through the renormalizat ion process and led to the crucial master equation. More recently, a n ew interpretation of the antifields has been developed. This interpret ation has cohomological origins and views the antifields as the genera tors of a differential complex that implements the gauge invariant equ ations of motion in cohomology. This note briefly reviews the construc tion of this complex and the cohomological interpretation of the antif ields.