Fourloop collinear anomalous dimension in N=4 YangMills theory
Abstract
We report a calculation in N=4 YangMills of the fourloop term g^{(4)} in the collinear anomalous dimension g(λ) which governs the universal subleading infrared structure of gluon scattering amplitudes. Using the method of obstructions to extract this quantity from the 1/γ singularity in the fourgluon iterative relation at four loops, we find g^{(4)}=1240.9 with an estimated numerical uncertainty of 0.02%. We also analyze the implication of our result for the strong coupling behavior of g(λ), finding support for the string theory prediction computed recently by Alday and Maldacena using AdS/CFT.
 Publication:

Physical Review D
 Pub Date:
 November 2007
 DOI:
 10.1103/PhysRevD.76.106004
 arXiv:
 arXiv:0707.1903
 Bibcode:
 2007PhRvD..76j6004C
 Keywords:

 11.25.Db;
 11.15.q;
 11.25.Tq;
 12.38.Bx;
 Properties of perturbation theory;
 Gauge field theories;
 Gauge/string duality;
 Perturbative calculations;
 High Energy Physics  Theory
 EPrint:
 5 pages, 2 figures