We introduce a new class of algebras, called reconstruction algebras, and present some of their basic properties. These non-commutative rings dictate in every way the process of resolving the Cohen-Macaulay singularities C-2/G where G = 1/r(1, a) <= GL(2,C).
- QUOTIENT SURFACE SINGULARITIES
- REFLEXIVE MODULES
- MCKAY CORRESPONDENCE