Representations of vertex operator algebras and bimodules

For a vertex operator algebra V a V-module M and a nonnegative integer n, an A(n)(V)-bimodule A(n)(M) is constructed and studied. The connections between A(n)(M) and intertwining operators are discussed. Moreover, the A(n)(V)-bimodule A(t,s)(V) is a quotient of A(n)(V) for all s, t <= n. In the case that V is rational, A(n)(M) for irreducible V-module M is given explicitly. (C) 2013 Elsevier Inc. All rights reserved.