TY - JOUR T1 - N = 2 Quiver Gauge Theories on A-type ALE Spaces Y1 - 2014 A1 - Ugo Bruzzo A1 - Francesco Sala A1 - Richard J. Szabo AB - We survey and compare recent approaches to the computation of the partition functions and correlators of chiral BPS observables in N = 2 gauge theories on ALE spaces based on quiver varieties and the minimal resolution Xk of the Ak-1 toric singularity C2/Zk, in light of their recently conjectured duality with two-dimensional coset conformal field theories. We review and elucidate the rigorous constructions of gauge theories for a particular family of ALE spaces, using their relation to the cohomology of moduli spaces of framed torsion-free sheaves on a suitable orbifold compactification of Xk. We extend these computations to generic N = 2 superconformal quiver gauge theories, obtaining in these instances new constraints on fractional instanton charges, a rigorous proof of the Nekrasov master formula, and new quantizations of Hitchin systems based on the underlying Seiberg–Witten geometry. PB - Springer UR - http://urania.sissa.it/xmlui/handle/1963/34719 U1 - 34918 U2 - Mathematics U4 - 1 ER -