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Related papers: Form factor recursion relations at loop level

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The boundary contribution of an amplitude in the BCFW recursion relation can be considered as a form factor involving boundary operator and unshifted particles. At the tree-level, we show that by suitable construction of Lagrangian, one can…

High Energy Physics - Theory · Physics 2016-06-29 Rijun Huang , Qingjun Jin , Bo Feng

We propose a new framework for computing three-point functions in planar $\mathcal{N}=4$ super Yang-Mills where these correlators take the form of multiple integrals of Separation of Variables type. We test this formalism at weak coupling…

High Energy Physics - Theory · Physics 2022-11-24 Carlos Bercini , Alexandre Homrich , Pedro Vieira

In this note, we study the $\mathcal{Q}$-cut representation by combining it with BCFW deformation. As a consequence, the one-loop integrand is expressed in terms of a recursion relation, i.e., $n$-point one-loop integrand is constructed…

High Energy Physics - Theory · Physics 2017-02-01 Bo Feng , Song He , Rijun Huang , Ming-xing Luo

In this paper we continue our systematic study of form factors of half-BPS operators in N=4 super Yang-Mills. In particular, we extend various techniques known for amplitudes to the case of form factors, including MHV rules, recursion…

High Energy Physics - Theory · Physics 2011-11-01 Andreas Brandhuber , Omer Gurdogan , Robert Mooney , Gabriele Travaglini , Gang Yang

We propose a bootstrap program for the {\it form factor squared} with operator ${\rm tr}(\phi^2)$ in maximally supersymmetric Yang-Mills theory in the planar limit, which plays a central role for perturbative calculations of important…

High Energy Physics - Theory · Physics 2025-06-10 Song He , Xiang Li , Jingwen Lin , Jiahao Liu , Kai Yan

Local, manifestly dual-conformally invariant loop integrands are now known for all finite quantities associated with observables in planar, maximally supersymmetric Yang-Mills theory through three loops. These representations, however, are…

High Energy Physics - Theory · Physics 2019-05-01 Jacob L. Bourjaily , Falko Dulat , Erik Panzer

In this paper we discuss different recursion relations (BCFW and all-line shift) for the form factors of the operators from the $\mathcal{N}=4$ SYM stress-tensor current supermultiplet $T^{AB}$ in momentum twistor space. We show that…

High Energy Physics - Theory · Physics 2016-09-28 L. V. Bork

We introduce a prescriptive approach to generalized unitarity, resulting in a strictly-diagonal basis of loop integrands with coefficients given by specifically-tailored residues in field theory. We illustrate the power of this strategy in…

High Energy Physics - Theory · Physics 2017-06-28 Jacob L. Bourjaily , Enrico Herrmann , Jaroslav Trnka

In this note we study the connected prescription, originally derived from Witten's twistor string theory, for tree-level form factors in ${\cal N}=4$ super-Yang-Mills theory. The construction is based on the recently proposed…

High Energy Physics - Theory · Physics 2016-12-19 Song He , Zhengwen Liu

The S-matrix for planar N = 4 super Yang-Mills theory can be computed as the correlation function for a holomorphic polygonal Wilson loop in twistor space. In an axial gauge, this leads to the construction of the all-loop integrand via MHV…

High Energy Physics - Theory · Physics 2015-06-12 Arthur E. Lipstein , Lionel Mason

Previously in \cite{Tao:2025fch}, we constructed the $\ell$-loop planar integrands using loop components and loop kernels by some recursion rules. In this paper, we propose a new formalism to express the loop kernel recursion. We define…

High Energy Physics - Theory · Physics 2026-04-23 Yi-Xiao Tao

Recently, loop integrands for certain Yang-Mills scattering amplitudes and correlation functions have been shown to be systematically expressible in dlog form, raising the possibility that these loop integrals can be performed directly…

High Energy Physics - Theory · Physics 2015-06-16 Arthur E. Lipstein , Lionel Mason

We review the results for the Sudakov form factor in N=4 super Yang-Mills theory up to the three-loop level. At each loop order, the form factor is expressed as a linear combination of only a handful scalar integrals, with small integer…

High Energy Physics - Theory · Physics 2012-10-05 Tobias Huber

We compute form factors in planar N=4 Super Yang-Mills at strong coupling. Namely we consider the overlap between an operator insertion and 2n gluons. Through the gauge/string duality these are given by minimal surfaces in AdS space. The…

High Energy Physics - Theory · Physics 2010-11-26 Juan Maldacena , Alexander Zhiboedov

In this PhD thesis we extend the twistor formalism to encompass (partially) off-shell quantities. We describe all gauge-invariant local composite operators in twistor space and show that they immediately generate all tree-level form factors…

High Energy Physics - Theory · Physics 2017-12-21 Laura Koster

Recently, an explicit, recursive formula for the all-loop integrand of planar scattering amplitudes in N=4 SYM has been described, generalizing the BCFW formula for tree amplitudes, and making manifest the Yangian symmetry of the theory.…

High Energy Physics - Theory · Physics 2015-05-20 Nima Arkani-Hamed , Jacob L. Bourjaily , Freddy Cachazo , Jaroslav Trnka

In this thesis, we study the integrands of a special four-point correlation function formed of protected half-BPS operators and scattering amplitudes in planar supersymmetric $\mathcal{N}=4$ Yang-Mills. We use the `soft-collinear bootstrap'…

High Energy Physics - Theory · Physics 2018-06-07 Vuong-Viet Tran

We use the soft-collinear bootstrap to construct the 8-loop integrand for the 4-point amplitude and 4-stress-tensor correlation function in planar maximally supersymmetric Yang-Mills theory. Both have a unique representation in terms of…

High Energy Physics - Theory · Physics 2016-05-18 Jacob L. Bourjaily , Paul Heslop , Vuong-Viet Tran

We study the three-point form factor of the length-three half-BPS operator ($\textrm{Tr}\,\phi^3$) in planar $\mathcal{N}=4$ Super-Yang-Mills theory, using analyticity and integrability methods. We find that the functions describing the…

High Energy Physics - Theory · Physics 2024-10-31 Benjamin Basso , Lance J. Dixon , Alexander G. Tumanov

We present an ansatz for the planar five-loop four-point amplitude in maximally supersymmetric Yang-Mills theory in terms of loop integrals. This ansatz exploits the recently observed correspondence between integrals with simple conformal…

High Energy Physics - Theory · Physics 2008-11-26 Z. Bern , J. J. M. Carrasco , H. Johansson , D. A. Kosower