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Related papers: All-loop cuts from the Amplituhedron

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The strict definition of positive geometry implies that all maximal residues of its canonical form are $\pm 1$. We observe, however, that the loop integrand of the amplitude in planar $\mathcal{N}=4$ super Yang-Mills has maximal residues…

High Energy Physics - Theory · Physics 2023-09-13 Gabriele Dian , Paul Heslop , Alastair Stewart

In this letter we compute a canonical set of cuts of the integrand for MHV amplitudes in planar ${\cal N}=4$ SYM, where all internal propagators are put on-shell. These "deepest cuts" probe the most complicated Feynman diagrams and on-shell…

High Energy Physics - Theory · Physics 2019-02-13 Nima Arkani-Hamed , Cameron Langer , Akshay Yelleshpur Srikant , Jaroslav Trnka

Inspired by the topological sign-flip definition of the Amplituhedron, we introduce similar, but distinct, positive geometries relevant for one-loop scattering amplitudes in planar $\mathcal{N}=4$ super Yang-Mills theory. The simplest…

High Energy Physics - Theory · Physics 2020-07-27 Enrico Herrmann , Cameron Langer , Jaroslav Trnka , Minshan Zheng

In this paper we focus on scattering amplitudes in maximally supersymmetric Yang-Mills theory and define a long sought-after geometry, the loop momentum amplituhedron, which we conjecture to encode tree and (the integrands of) loop…

High Energy Physics - Theory · Physics 2023-06-07 Livia Ferro , Tomasz Lukowski

In this paper, we define the momentum amplituhedron in the four-dimensional split-signature space of dual momenta. It encodes scattering amplitudes at tree level and loop integrands for N=4 super Yang-Mills in the planar sector. In this…

High Energy Physics - Theory · Physics 2023-08-07 Livia Ferro , Ross Glew , Tomasz Lukowski , Jonah Stalknecht

We define and study a positive geometry $\Delta^{(L)}$ which serves as a natural generalization of loop amplituhedra to two-dimensional Minkowski space $\mathbb{R}^{1,1}$. The geometry is formulated in the framework of lightcone geometries…

High Energy Physics - Theory · Physics 2026-04-02 Jonah Stalknecht

We present new, fundamentally combinatorial and topological characterizations of the amplituhedron. Upon projecting external data through the amplituhedron, the resulting configuration of points has a specified (and maximal) generalized…

High Energy Physics - Theory · Physics 2018-02-14 Nima Arkani-Hamed , Hugh Thomas , Jaroslav Trnka

In this paper, we define the ABJM loop momentum amplituhedron, which is a geometry encoding ABJM planar tree-level amplitudes and loop integrands in the three-dimensional spinor helicity space. Translating it to the space of dual momenta…

High Energy Physics - Theory · Physics 2023-07-10 Tomasz Lukowski , Jonah Stalknecht

This thesis investigates geometric descriptions of scattering amplitudes, with a specific focus on scattering amplitudes in N=4 SYM and ABJM theory. The recent development of the field of positive geometries provides us with a suitable…

High Energy Physics - Theory · Physics 2024-09-25 Jonah Stalknecht

In this paper, we consider the triangulation of 2-loop MHV amplituhedron from "sign flip" definition. Using the isomorphism between $m=2, k=2$ tree amplituhedron and 1-loop MHV physical amplituhedron, we found the direct triangulation of…

High Energy Physics - Theory · Physics 2019-04-16 Ryota Kojima

We study correlators of null, $n$-sided polygonal Wilson loops with a Lagrangian insertion in the planar limit of the ${\cal N}=4$ supersymmetric Yang-Mills theory. This finite observable is closely related to loop integrands of…

High Energy Physics - Theory · Physics 2025-03-24 Taro V. Brown , Johannes M. Henn , Elia Mazzucchelli , Jaroslav Trnka

The amplituhedron provides a beautiful description of perturbative superamplitude integrands in N=4 SYM in terms of purely geometric objects, generalisations of polytopes. On the other hand the Wilson loop in supertwistor space also gives…

High Energy Physics - Theory · Physics 2018-11-14 Paul Heslop , Alastair Stewart

In this paper we define a new object, the momentum amplituhedron, which is the long sought-after positive geometry for tree-level scattering amplitudes in $\mathcal{N}=4$ super Yang-Mills theory in spinor helicity space. Inspired by the…

High Energy Physics - Theory · Physics 2019-09-04 David Damgaard , Livia Ferro , Tomasz Lukowski , Matteo Parisi

The loop-Amplituhedron $\mathcal{A}^{(L)}_{n}$ is a semialgebraic set in the product of Grassmannians $\mathrm{Gr}_{\mathbb{R}}(2,4)^L$. Recently, many aspects of this geometry for the case of $L=1$ have been elucidated, such as its…

High Energy Physics - Theory · Physics 2026-04-08 Gabriele Dian , Elia Mazzucchelli , Felix Tellander

Scattering amplitudes in planar ${\cal N}=4$ supersymmetric Yang-Mills theory are dual to expectation values of null polygonal Wilson loops. The Amplituhedron provides a geometric construction for the all-loop integrand as the canonical…

High Energy Physics - Theory · Physics 2026-05-29 Lance J. Dixon , Umut Oktem , Shruti Paranjape , Jaroslav Trnka , Yongqun Xu , Shun-Qing Zhang

All-loop planar scattering amplitudes in maximally supersymmetric Yang-Mills theory can be formulated geometrically in terms of the "amplituhedron". We study the mathematical structures of the one-loop amplituhedron, and present a new…

High Energy Physics - Theory · Physics 2016-02-17 Yuntao Bai , Song He , Thomas Lam

We consider the recursion relation for loop integrands in planar N = 4 SYM generated by an all-line shift of momentum twistors. We examine the behaviour of the rational loop integrands when the shift parameter becomes large, and find that a…

High Energy Physics - Theory · Physics 2015-05-20 Mathew Bullimore

We present the general flux tube integrand for MHV and non-MHV amplitudes, in planar N = 4 SYM theory, up to a group theoretical rational factor. We find that the MHV and non-MHV cases only differ by simple form factors which we derive.…

High Energy Physics - Theory · Physics 2016-07-26 Benjamin Basso , Joao Caetano , Lucia Cordova , Amit Sever , Pedro Vieira

The amplituhedron is a semialgebraic set given as the image of the non-negative Grassmannian under a linear map subject to a choice of additional parameters. We define the limit amplituhedron as the limit of amplituhedra by sending one of…

Algebraic Geometry · Mathematics 2025-01-15 Joris Koefler , Rainer Sinn

Positive geometries provide a modern approach for computing scattering amplitudes in a variety of physical models. In order to facilitate the exploration of these new geometric methods, we introduce a Mathematica package called…

High Energy Physics - Theory · Physics 2020-10-28 Tomasz Lukowski , Robert Moerman