Quantum integrability in (super) Yang-Mills theory on the light-cone

We employ the light-cone formalism to construct in the (super) Yang-Mills theories in the multi-color limit the one-loop dilatation operator acting on single trace products of chiral superfields separated by light-like distances. In the N = 4 YangMills theory it exhausts all Wilson operators of the maximal Lorentz spin while in nonsupersymmetric Yang-Mills theory it is restricted to the sector of maximal helicity gluonic operators. We show that the dilatation operator in all Ar-extended super-Yang-Mills theories is given by the same integral operator which acts on the (N+I)-dimensional superspace and is invariant under the SL(2\N) superconformal transformations. We construct the R-matrix on this space and identify the dilatation operator as the Hamiltonian of the Heisenberg SL(2\N) spin chain. (C) 2004 Elsevier B.V. All rights reserved.