Rigid surface operators and S-duality: some proposals

Understand

We study surface operators in the N=4 supersymmetric Yang-Mills theories with gauge groups SO(n) and Sp(2n).

• As recently shown by Gukov and Witten these theories have a class of rigid surface operators which are expected to be related by S-duality.
• The rigid surface operators are of two types, unipotent and semisimple.
• We make explicit proposals for how the S-duality map should act on unipotent surface operators.