String corrections to four point functions in the AdS/CFT correspondence

In a string calculation to order alpha'(3), we compute an eight-derivative four-dilaton term in the type IIB effective action. Following the AdS prescription, we compute the order (g(YM)(2)N(c))(-3/2) correction to the foul-point correlation function involving the operator trF(2) in four dimensional N = 4 super Yang-Mills using the string corrected type TIE action extending the work of Freedman et al. (hep-th/9808006). In the limit where: two of the Yang-Mills operators approach each other, we find that out correction to the four-point correlation functions develops a logarithmic singularity. We discuss the possible cancellation of this logarithmic singularities by conjecturing new terms in the type IIB effective action. (C) 1999 Elsevier Science B.V. All rights reserved.