TY - JOUR

T1 - Manifest ultraviolet behavior for the three-loop four-point amplitude of N=8 supergravity

AU - Bern, Z.

AU - Carrasco, J. J.M.

AU - Dixon, L. J.

AU - Johansson, H.

AU - Roiban, R.

N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.

PY - 2008/11/20

Y1 - 2008/11/20

N2 - Using the method of maximal cuts, we obtain a form of the three-loop four-point scattering amplitude of N=8 supergravity in which all ultraviolet cancellations are made manifest. The Feynman loop integrals that appear have a graphical representation with only cubic vertices, and numerator factors that are quadratic in the loop momenta, rather than quartic as in the previous form. This quadratic behavior reflects cancellations beyond those required for finiteness, and matches the quadratic behavior of the three-loop four-point scattering amplitude in N=4 super-Yang-Mills theory. By direct integration we confirm that no additional cancellations remain in the N=8 supergravity amplitude, thus demonstrating that the critical dimension in which the first ultraviolet divergence occurs at three loops is Dc=6. We also give the values of the three-loop divergences in D=7, 9, 11. In addition, we present the explicitly color-dressed three-loop four-point amplitude of N=4 super-Yang-Mills theory.

AB - Using the method of maximal cuts, we obtain a form of the three-loop four-point scattering amplitude of N=8 supergravity in which all ultraviolet cancellations are made manifest. The Feynman loop integrals that appear have a graphical representation with only cubic vertices, and numerator factors that are quadratic in the loop momenta, rather than quartic as in the previous form. This quadratic behavior reflects cancellations beyond those required for finiteness, and matches the quadratic behavior of the three-loop four-point scattering amplitude in N=4 super-Yang-Mills theory. By direct integration we confirm that no additional cancellations remain in the N=8 supergravity amplitude, thus demonstrating that the critical dimension in which the first ultraviolet divergence occurs at three loops is Dc=6. We also give the values of the three-loop divergences in D=7, 9, 11. In addition, we present the explicitly color-dressed three-loop four-point amplitude of N=4 super-Yang-Mills theory.

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U2 - 10.1103/PhysRevD.78.105019

DO - 10.1103/PhysRevD.78.105019

M3 - Article

AN - SCOPUS:57149142775

VL - 78

JO - Physical Review D

JF - Physical Review D

SN - 0556-2821

IS - 10

M1 - 105019

ER -