'Holey sheets' - Pfaffians and subdeterminants as D-brane operators in large N gauge theories

In the AdS/CFT correspondence, wrapped D3-branes (such as 'giant gravitons') on the string theory side of the correspondence have been identified with pfaffian, determinant and subdeterminant operators on the field theory side. We substantiate this identification by showing that the presence of pairs of such operators in a correlation function of a large-N gauge theory naturally leads to a modified 't Hooft expansion including also worldsheets with boundaries. This happens independently of supersymmetry or conformal invariance. (author)