Quivers as Calculators: Counting, Correlators and Riemann Surfaces

Understand

The spectrum of chiral operators in supersymmetric quiver gauge theories is typically much larger in the free limit, where the superpotential terms vanish.

• We find that the finite N counting of operators in any free quiver theory, with a product of unitary gauge groups, can be described by associating Young diagrams and Littlewood-Richardson multiplicities to a simple modification of the quiver, which we call the split-node quiver.
• The large N limit leads to a surprisingly simple infinite product formula for counting gauge invariant operators, valid for any quiver with bifundamental fields.
• An orthogonal basis for the operators, in the finite N CFT inner product, is given in terms of quiver characters.