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Related papers: Four-point amplitudes in $\mathcal{N}=2$ SCQCD

200 papers

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

We derive analytic results for the symbol of certain two-loop Feynman integrals relevant for seven- and eight-point two-loop scattering amplitudes in planar $\mathcal{N}=4$ super-Yang--Mills theory. We use a bootstrap inspired strategy,…

High Energy Physics - Theory · Physics 2018-11-14 Johannes Henn , Enrico Herrmann , Julio Parra-Martinez

Some of the difficulties faced when calculating multi-loop amplitudes with several mass scales are reviewed. We then focus on one particular difficulty, the evaluation of the Feynman integrals, and introduce the program pySecDec which can…

High Energy Physics - Phenomenology · Physics 2018-06-08 S. P. Jones , B. Ruijl

We generalize modern ideas about the duality between Wilson loops and scattering amplitudes in ${\cal N}=4$ SYM to large $N$ QCD by deriving a general relation between QCD meson scattering amplitudes and Wilson loops. We then investigate…

High Energy Physics - Theory · Physics 2013-05-29 Yuri Makeenko , Poul Olesen

We describe the unitarity approach for the numerical computation of two-loop integral coefficients of scattering amplitudes. It is well known that the leading propagator singularities of an amplitude's integrand are related to products of…

High Energy Physics - Phenomenology · Physics 2017-06-07 S. Abreu , F. Febres Cordero , H. Ita , M. Jaquier , B. Page

We study an alternative to dimensional regularisation of planar scattering amplitudes in N=4 super Yang-Mills theory by going to the Coulomb phase of the theory. The infrared divergences are regulated by masses obtained from a Higgs…

High Energy Physics - Theory · Physics 2011-01-24 Luis F. Alday , Johannes M. Henn , Jan Plefka , Theodor Schuster

We expose simple and practical relations between the integrated four- and five-point one-loop amplitudes of N >= 4 supergravity and the corresponding (super-)Yang-Mills amplitudes. The link between the amplitudes is simply understood using…

High Energy Physics - Theory · Physics 2013-05-29 Z. Bern , C. Boucher-Veronneau , H. Johansson

We consider the two-loop four-point amplitude in N=2 super QED, and show that there exists an approximate recursive structure similar to that captured by the ABDK/BDS ansatz for MHV amplitudes in N=4 super Yang-Mills. Furthermore, we…

High Energy Physics - Theory · Physics 2009-08-11 Andreas Brandhuber , Gabriele Travaglini , Massimiliano Vincon

Scattering amplitudes in planar N=4 super Yang-Mills theory reveal a remarkable symmetry structure. In addition to the superconformal symmetry of the Lagrangian of the theory, the planar amplitudes exhibit a dual superconformal symmetry.…

High Energy Physics - Theory · Physics 2015-05-20 J. M. Drummond

We compute the three-loop correction to the universal single-soft emission current for the case of scattering amplitudes with two additional color-charged partons. We present results valid for QCD and $\mathcal{N}=4$ super-symmetric…

High Energy Physics - Phenomenology · Physics 2023-09-15 Franz Herzog , Yao Ma , Bernhard Mistlberger , Adi Suresh

It is pointed out the ${\cal N}=4$ supersymmetric gauge theory used in the anti-de Sitter holographic correspondence is required to be modified. The SL(2,Z) completion of the theory is required to map the correlators to string theory…

General Physics · Physics 2007-05-23 Gordon Chalmers

We show how generalised unitarity cuts in D = 4 - 2 epsilon dimensions can be used to calculate efficiently complete one-loop scattering amplitudes in non-supersymmetric Yang-Mills theory. This approach naturally generates the rational…

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

Using a careful choice of infrared (IR) subtraction scheme, we demonstrate the cancellation of all terms with transcendental weights 0,1,2 from the finite part of the full-color two-loop four-gluon $\mathcal{N}=2$ supersymmetric QCD…

High Energy Physics - Theory · Physics 2020-02-19 Gregor Kälin , Gustav Mogull , Alexander Ochirov , Bram Verbeek

We present the complete integrands of five-point superamplitudes in N=4 super-Yang-Mills theory and N=8 supergravity, at one and two loops, for four-dimensional external states and D-dimensional internal kinematics. For N=4 super-Yang-Mills…

High Energy Physics - Theory · Physics 2012-01-18 John Joseph M. Carrasco , Henrik Johansson

We comment on the status of "Steinmann-like" constraints, i.e. all-loop constraints on consecutive entries of the symbol of scattering amplitudes and Feynman integrals in planar ${\cal N}=4$ super-Yang-Mills, which have been crucial for the…

High Energy Physics - Theory · Physics 2022-02-02 Song He , Zhenjie Li , Qinglin Yang

Infrared divergences in scattering amplitudes arise when a loop momentum $\ell$ becomes collinear with a massless external momentum $p$. In gauge theories, it is known that the L-loop logarithm of a planar amplitude has much softer infrared…

High Energy Physics - Theory · Physics 2015-06-03 Jacob L. Bourjaily , Alexander DiRe , Amin Shaikh , Marcus Spradlin , Anastasia Volovich

One of the main challenges in obtaining predictions for collider experiments from perturbative quantum field theory, is the direct evaluation of the Feynman integrals it gives rise to. In this chapter, we review an alternative bootstrap…

High Energy Physics - Theory · Physics 2023-01-27 Georgios Papathanasiou

We initiate a comprehensive investigation of the geometry of the amplituhedron, a recently found geometric object whose volume calculates the integrand of scattering amplitudes in planar N=4 SYM theory. We do so by introducing and studying…

High Energy Physics - Theory · Physics 2014-08-18 Sebastian Franco , Daniele Galloni , Alberto Mariotti , Jaroslav Trnka

The perturbative approach to quantum field theories has made it possible to obtain incredibly accurate theoretical predictions in high-energy physics. Although various techniques have been developed to boost the efficiency of these…

High Energy Physics - Phenomenology · Physics 2021-05-05 Selomit Ramirez-Uribe , Roger J. Hernandez-Pinto , German Rodrigo , German F. R. Sborlini , William J. Torres Bobadilla

We use unitarity techniques to compute the two-loop non-planar corrections to the Sudakov form factor and the four-point amplitude in ABJM theory. We start by reconstructing non-planar integrals from two-particle cuts in three dimensions.…

High Energy Physics - Theory · Physics 2014-07-09 Lorenzo Bianchi , Marco S. Bianchi