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Related papers: A recursive method for SYM n-point tree amplitudes

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We review generalized unitarity as a means for obtaining loop amplitudes from on-shell tree amplitudes. The method is generally applicable to both supersymmetric and non-supersymmetric amplitudes, including non-planar contributions. Here we…

High Energy Physics - Theory · Physics 2015-05-27 Zvi Bern , Yu-tin Huang

We give a comprehensive review of recent developments on using the pure spinor formalism to compute massless superstring scattering amplitudes at tree level. The main results of the pure spinor computations are placed into the context of…

High Energy Physics - Theory · Physics 2023-05-24 Carlos R. Mafra , Oliver Schlotterer

The BRST cohomology of the N=2 supersymmetric Yang-Mills theory in four dimensions is discussed by making use of the twisted version of the N=2 algebra. By the introduction of a set of suitable constant ghosts associated to the generators…

High Energy Physics - Theory · Physics 2008-11-26 A. Tanzini , O. S. Ventura , L. C. Q. Vilar , S. P. Sorella

The study of collinear behavior for gauge theories in the spacelike region is of great phenomenological and theoretical importance. We analytically calculate the two-loop spacelike splitting amplitude for the full color N=4 Super-Yang-Mills…

High Energy Physics - Theory · Physics 2024-08-06 Johannes Henn , Rourou Ma , Yongqun Xu , Kai Yan , Yang Zhang , Hua Xing Zhu

We use the pure spinor formalism to obtain the supersymmetric massless five-point amplitude at tree-level in a streamlined fashion. We also prove the equivalence of an OPE identity in string theory with a subset of the…

High Energy Physics - Theory · Physics 2010-01-22 Carlos R. Mafra

As an alternative to the usual Feynman graphs, tree amplitudes in Yang-Mills theory can be constructed from tree graphs in which the vertices are tree level MHV scattering amplitudes, continued off shell in a particular fashion. The…

High Energy Physics - Theory · Physics 2010-04-07 Freddy Cachazo , Peter Svrcek , Edward Witten

We argue that generic one-loop scattering amplitudes in supersymmetric Yang-Mills theories can be computed equivalently with MHV diagrams or with Feynman diagrams. We first present a general proof of the covariance of one-loop non-MHV…

High Energy Physics - Theory · Physics 2009-11-11 Andreas Brandhuber , Bill Spence , Gabriele Travaglini

The simplicity and hidden symmetries of (Super) Yang-Mills and (Super)Gravity scattering amplitudes suggest the existence of a "weak-weak" dual formulation in which these structures are made manifest at the expense of manifest locality. We…

High Energy Physics - Theory · Physics 2015-05-13 Nima Arkani-Hamed , Freddy Cachazo , Clifford Cheung , Jared Kaplan

By means of a kinematic analysis of tree level graviton amplitudes we find, at least through six points, that the reason of their decompositon as a sum over products of Yang-Mills amplitudes is on-shell gauge invariance and unitarity. As a…

High Energy Physics - Theory · Physics 2020-02-19 Luiz Antonio Barreiro , Ricardo Medina

The Grassmannian formulation of $\mathcal{N}=4$ super Yang-Mills theory expresses tree-level scattering amplitudes as linear combinations of residues from certain contour integrals. BCFW bridge decompositions using adjacent transpositions…

High Energy Physics - Theory · Physics 2014-11-25 Timothy M. Olson

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…

Planar N=4 super Yang-Mills appears to be integrable. While this allows to find this theory's exact spectrum, integrability has hitherto been of no direct use for scattering amplitudes. To remedy this, we deform all scattering amplitudes by…

High Energy Physics - Theory · Physics 2013-03-27 Livia Ferro , Tomasz Lukowski , Carlo Meneghelli , Jan Plefka , Matthias Staudacher

We initiate an exploration of on-shell functions in $\mathcal{N}=4$ SYM beyond the planar limit by providing compact, combinatorial expressions for all leading singularities of MHV amplitudes and showing that they can always be expressed as…

High Energy Physics - Theory · Physics 2014-12-31 Nima Arkani-Hamed , Jacob L. Bourjaily , Freddy Cachazo , Alexander Postnikov , Jaroslav Trnka

We have calculated the high spin parton splitting amplitudes postulating the Yangian symmetry of the scattering amplitudes for tensorgluons. The resulting splitting amplitudes coincide with the earlier calculations, which were based on the…

High Energy Physics - Theory · Physics 2017-07-10 Roland Kirschner , George Savvidy

We review two novel techniques used to calculate tree-level scattering amplitudes efficiently: MHV diagrams, and on-shell recursion relations. For the MHV diagrams, we consider applications to tree-level amplitudes and focus in particular…

High Energy Physics - Theory · Physics 2015-05-27 Andreas Brandhuber , Bill Spence , Gabriele Travaglini

We present an expression for the leading-color (planar) four-loop four-point amplitude of N=4 supersymmetric Yang-Mills theory in 4-2 e dimensions, in terms of eight separate integrals. The expression is based on consistency of unitarity…

High Energy Physics - Theory · Physics 2008-11-26 Zvi Bern , Michael Czakon , Lance J. Dixon , David A. Kosower , Vladimir A. Smirnov

We report on a systematic perturbative study of three-point functions in planar SU(N) N=4 super Yang-Mills theory at the one-loop level involving scalar field operators up to length five. For this we have computed a sample of 40 structure…

High Energy Physics - Theory · Physics 2015-06-03 George Georgiou , Valeria Gili , Andre Grossardt , Jan Plefka

We calculate form factors of half-BPS operators in N=4 super Yang-Mills theory at tree level and one loop using novel applications of recursion relations and unitarity. In particular, we determine the expression of the one-loop form factors…

High Energy Physics - Theory · Physics 2011-02-03 Andreas Brandhuber , Bill Spence , Gabriele Travaglini , Gang Yang

The N=1,d=10 superYang-Mills action is constructed in a twisted form, using SU(5)-invariant decomposition of spinors in 10 dimensions. The action and its off-shell closed twisted scalar supersymmetry operator Q derive from a Chern-Simons…

High Energy Physics - Theory · Physics 2011-03-21 Laurent Baulieu

We compute tree-level $n$-point scattering amplitudes in scalar field theories in terms of geometric invariants on a fibre bundle. All 0- and 2-derivative interactions are incorporated into a metric on this bundle. The on-shell amplitudes…

High Energy Physics - Theory · Physics 2025-09-26 Mohammad Alminawi , Ilaria Brivio , Joe Davighi