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We explore scattering amplitudes on the Coulomb branch of maximally supersymmetric Yang-Mills theory. We introduce a particular pattern of scalar vacuum expectation values that allow us to define amplitudes with a different mass pattern…

High Energy Physics - Theory · Physics 2025-02-05 Wojciech Flieger , Johannes Henn , Anders Schreiber , Jaroslav Trnka

I present a conjecture that all two-loop MHV amplitudes in planar $\mathcal{N} = 4$ super-Yang-Mills theory possess an antipodal symmetry when evaluated on parity-even kinematics. The symmetry acts as a change of basis on the symbol…

High Energy Physics - Theory · Physics 2022-09-28 Yu-Ting Liu

We compute one-loop matter amplitudes in homogeneous Maxwell-Einstein supergravities with N=2 supersymmetry using the double-copy construction. We start from amplitudes of N=2 super-Yang-Mills theory with matter that obey manifestly the…

High Energy Physics - Theory · Physics 2019-05-01 Maor Ben-Shahar , Marco Chiodaroli

In previous work, the two-loop five-point amplitudes in $\mathcal{N}=4$ super Yang-Mills theory and $\mathcal{N}=8$ supergravity were computed at symbol level. In this paper, we compute the full functional form. The amplitudes are assembled…

High Energy Physics - Theory · Physics 2020-12-02 Simon Caron-Huot , Dmitry Chicherin , Johannes Henn , Yang Zhang , Simone Zoia

We show that a certain class of light-like Wilson loops exhibits a Yangian symmetry at one loop, or equivalently, in an Abelian theory. The Wilson loops we discuss are equivalent to one-loop MHV amplitudes in N=4 super Yang-Mills theory in…

High Energy Physics - Theory · Physics 2015-05-20 J. M. Drummond , L. Ferro , E. Ragoucy

We present an explicit formula for the n-point MHV one-loop amplitude in a N=4 supergravity theory. This formula is derived from the soft and collinear factorisations of the amplitude.

High Energy Physics - Theory · Physics 2015-06-03 David C. Dunbar , James H. Ettle , Warren B. Perkins

We re-compute the recently derived two-loop five-point all plus Yang-Mills amplitude using Unitarity and Recursion. Recursion requires augmented recursion to determine the sub-leading pole. Using these methods the simplicity of this…

High Energy Physics - Theory · Physics 2016-04-27 David C. Dunbar , Warren B. Perkins

We compute the four-point amplitude with external adjoint particles in $\mathcal{N}=2$ SCQCD at two loops using $\mathcal{N}=1$ superspace Feynman diagrams, extending the results of arXiv:1406.7283. We consider the diagrammatic difference…

High Energy Physics - Theory · Physics 2015-06-15 Marta Leoni , Andrea Mauri , Alberto Santambrogio

We apply a bootstrap procedure to two-loop MHV amplitudes in planar N=4 super-Yang-Mills theory. We argue that the mathematically most complicated part (the $\Lambda^2 B_2$ coproduct component) of the n-particle amplitude is uniquely…

High Energy Physics - Theory · Physics 2015-06-23 John Golden , Marcus Spradlin

We prove that 1-loop n-point NMHV superamplitudes in N=4 SYM theory are dual conformal covariant for all numbers n of external particles (after regularization and subtraction of IR divergences). This property was previously established for…

High Energy Physics - Theory · Physics 2015-05-13 Henriette Elvang , Daniel Z. Freedman , Michael Kiermaier

In this thesis, we study the all same helicity loop amplitudes in self-dual Yang-Mills and self-dual gravity. These amplitudes have long been conjectured to be interpreted as an anomaly and are recently linked to the UV divergence of…

High Energy Physics - Theory · Physics 2023-10-24 Pratik Chattopadhyay

A previously proposed all-loop-orders relation between the Regge limits of four-point amplitudes of N=4 supersymmetric Yang-Mills theory and N=8 supergravity is established at the three-loop level. We show that the Regge limit of known…

High Energy Physics - Theory · Physics 2022-07-08 Stephen G. Naculich , Theodore W. Wecker

We investigate generic properties of one-loop amplitudes in unordered gauge theories in four dimensions. For such theories the organisation of amplitudes in manifestly crossing symmetric expressions poses restrictions on their structure and…

High Energy Physics - Theory · Physics 2012-05-03 Simon Badger , N. E. J. Bjerrum-Bohr , Pierre Vanhove

N=4 supersymmetric Yang-Mills theory exhibits a rather surprising duality of Wilson-loop vacuum expectation values and scattering amplitudes. In this paper, we investigate this correspondence at the diagram level. We find that one-loop…

High Energy Physics - Theory · Physics 2015-03-17 Charalampos Anastasiou , Andrea Banfi

Using cutting techniques we obtain the two-loop N=4 super-Yang-Mills helicity amplitudes for four-gluon scattering in terms of scalar integral functions. The N=4 amplitudes are considerably simpler than corresponding QCD amplitudes and…

High Energy Physics - Phenomenology · Physics 2009-10-30 Z. Bern , J. S. Rozowsky , B. Yan

We extend the twistor string theory inspired formalism introduced in hep-th/0407214 for calculating loop amplitudes in N=4 super Yang-Mills theory to the case of N=1 (and N=2) super Yang-Mills. Our approach yields a novel representation of…

High Energy Physics - Theory · Physics 2011-05-05 James Bedford , Andreas Brandhuber , Bill Spence , Gabriele Travaglini

A study of the colour-ordered one-loop amplitudes in N=4 SYM reveals a surprising property: numerically, the amplitudes have an Approximately Universal form A^{1-loop}_n ~ A^{tree}_n \times U_n, where U_n is helicity independent. This form…

High Energy Physics - Theory · Physics 2009-03-27 David C. Dunbar , James H. Ettle , Warren B. Perkins

We exploit the recently described property of cluster adjacency for scattering amplitudes in planar $\mathcal{N}=4$ super Yang-Mills theory to construct the symbol of the four-loop NMHV heptagon amplitude. We use a manifestly cluster…

High Energy Physics - Theory · Physics 2020-04-16 James Drummond , Jack Foster , Ömer Gürdoğan , Georgios Papathanasiou

A novel way of computing high-order amplitudes in the multi-Regge limit of planar maximally supersymmetric Yang-Mills theory is presented. In this framework, we are able to obtain high-loop and high-leg results by an easy operation on known…

Pure Yang-Mills amplitudes with all external gluons carrying positive helicity, known as all-plus amplitudes, have an especially simple structure. The tree amplitudes vanish and, up to at least two loops, the loop-level amplitudes are…

High Energy Physics - Theory · Physics 2017-07-21 Gustav Mogull