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We compute for the first time the two-loop corrections to arbitrary n-gon lightlike Wilson loops in N=4 supersymmetric Yang-Mills theory, using efficient numerical methods. The calculation is motivated by the remarkable agreement between…

High Energy Physics - Theory · Physics 2010-06-29 Charalampos Anastasiou , Andreas Brandhuber , Paul Heslop , Valentin V. Khoze , Bill Spence , Gabriele Travaglini

We compute the even part of the two-loop seven-point planar MHV amplitude in N=4 supersymmetric Yang-Mills theory. We find that the even part is expressed in terms of conformal integrals with simple rational coefficients. We also compute…

High Energy Physics - Theory · Physics 2009-06-30 C. Vergu

The precise form of the multi-Regge asymptotics of the two-loop six-point MHV amplitude in N = 4 Super-Yang-Mills theory has been a subject of recent controversy. In this paper we utilize the amplitude/Wilson loop correspondence to obtain…

High Energy Physics - Theory · Physics 2010-02-25 Robert M. Schabinger

We derive a compact expression for the three-point MHV form factors of half-BPS operators in N=4 super Yang-Mills at two loops. The main tools of our calculation are generalised unitarity applied at the form factor level, and the compact…

High Energy Physics - Theory · Physics 2015-06-03 Andreas Brandhuber , Gabriele Travaglini , Gang Yang

It is a remarkable fact that MHV amplitudes in maximally supersymmetric Yang-Mills theory at arbitrary loop order can be written as the product of the tree amplitude with the same helicity configuration and a universal, helicity-blind…

High Energy Physics - Theory · Physics 2008-11-26 Andreas Brandhuber , Paul Heslop , Gabriele Travaglini

We compute the symbol of the two-loop five-point amplitude in $\mathcal N=8$ supergravity. We write an ansatz for the amplitude whose rational prefactors are based on not only 4-dimensional leading singularities, but also $d$-dimensional…

High Energy Physics - Theory · Physics 2019-03-27 Samuel Abreu , Lance J. Dixon , Enrico Herrmann , Ben Page , Mao Zeng

The superconformal Ward identities combined with N=2 harmonic analyticity are used to evaluate two-loop four-point correlation functions of gauge-invariant operators in D=4, N=4 supersymmetric Yang-Mills theory in terms of the well-known…

High Energy Physics - Theory · Physics 2015-06-26 B. Eden , P. S. Howe , C. Schubert , E. Sokatchev , P. C. West

In this review we discuss some recent developments related to one-loop N = 4 super Yang-Mills scattering amplitudes calculated to all orders in epsilon. It is often the case that one-loop gauge theory computations are carried out to order…

High Energy Physics - Theory · Physics 2015-05-27 Robert M. Schabinger

We provide two derivations of the one-loop dual conformal anomaly of generic n-point superamplitudes in maximally supersymmetric Yang-Mills theory. Our proofs are based on simple applications of unitarity, and the known analytic properties…

High Energy Physics - Theory · Physics 2009-11-09 Andreas Brandhuber , Paul Heslop , Gabriele Travaglini

For scattering amplitudes in strong background fields, it is -- at least in principle -- possible to perturbatively expand the background to obtain higher-point vacuum amplitudes. In the case of self-dual plane wave backgrounds we consider…

High Energy Physics - Theory · Physics 2022-01-19 Tim Adamo , Anton Ilderton , Alexander J. MacLeod

Supersymmetric integrands for the two-loop five-point amplitudes in ten-dimensional super Yang--Mills and type II supergravity are proposed. The kinematic numerators are manifestly local and satisfy the duality between color and kinematics…

High Energy Physics - Theory · Physics 2015-11-05 Carlos R. Mafra , Oliver Schlotterer

The two-loop four-point amplitude of two massless SU(N) colored scalars and two color singlet operators with different virtuality described by a half-BPS and Konishi operators is calculated analytically in maximally supersymmetric…

High Energy Physics - Theory · Physics 2020-12-01 Taushif Ahmed , Prasanna K. Dhani

We argue that the scattering amplitudes in the maximally supersymmetric N=4 super-Yang-Mills theory possess a new symmetry which extends the previously discovered dual conformal symmetry. To reveal this property we formulate the scattering…

High Energy Physics - Theory · Physics 2009-12-22 J. M. Drummond , J. Henn , G. P. Korchemsky , E. Sokatchev

We use momentum twistors to evaluate planar loop integrals. Infrared divergences are regulated by the recently proposed AdS-inspired mass regulator. We show that two-loop amplitudes in N=4 super Yang-Mills can be expanded in terms of basis…

High Energy Physics - Theory · Physics 2011-05-26 J. M. Drummond , J. M. Henn

We study four point planar loop amplitudes at an arbitrary point in the Coulomb branch of $\mathcal{N}=4$ super-Yang-Mills theory. We study two particle unitary cuts up to four loop order. We explicitly verify that bubble and triangle…

High Energy Physics - Theory · Physics 2024-05-01 Md. Abhishek , Subramanya Hegde , Dileep P. Jatkar , Arnab Priya Saha , Amit Suthar

In this letter, we exploit generalised unitarity in order to calculate the cut-constructible part of one-loop amplitudes in non-supersymmetric Yang-Mills theory. In particular, we rederive the n-gluon MHV amplitudes for both the adjacent…

High Energy Physics - Phenomenology · Physics 2010-02-03 Andreas Brandhuber , Massimiliano Vincon

We show how the MHV diagram description of Yang-Mills theories can be used to study non-supersymmetric loop amplitudes. In particular, we derive a compact expression for the cut-constructible part of the general one-loop MHV multi-gluon…

High Energy Physics - Theory · Physics 2010-12-14 James Bedford , Andreas Brandhuber , Bill Spence , Gabriele Travaglini

We conjecture a simple relationship between the one-loop maximally helicity violating gluon amplitudes of ordinary QCD (all helicities identical) and those of N=4 supersymmetric Yang-Mills (all but two helicities identical). Because the…

High Energy Physics - Theory · Physics 2009-07-09 Z. Bern , L. Dixon , D. C. Dunbar , D. A. Kosower

We consider the factorisation of one-loop amplitudes at complex kinematic points. By determining the terms that are absent for real kinematics, we can construct a recursive ansatz for the purely rational pieces of one-loop amplitudes in…

High Energy Physics - Theory · Physics 2013-05-30 Sam D. Alston , David C. Dunbar , Warren B. Perkins

Using four-dimensional unitarity and MHV-rules we calculate the one-loop MHV amplitudes with all external particles in the adjoint representation for N=2 supersymmetric QCD with N_f fundamental flavours. We start by considering such…

High Energy Physics - Theory · Physics 2014-11-18 E. W. Nigel Glover , Valentin V. Khoze , Ciaran Williams