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Related papers: Macroscopic loop amplitudes in the multi-cut two-m…

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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

We show how to compute the coefficients of the double box basis integrals in a massless four-point amplitude in terms of tree amplitudes. We show how to choose suitable multidimensional contours for performing the required cuts, and derive…

High Energy Physics - Theory · Physics 2013-05-30 David A. Kosower , Kasper J. Larsen

We study perturbations around the generalized Kazakov multicritical one-matrix model. The multicritical matrix model has a potential where the coefficients of $z^n$ only fall off as a power $1/n^{s+1}$. This implies that the potential and…

High Energy Physics - Theory · Physics 2018-03-14 J. Ambjorn , L. Chekhov , Y. Makeenko

We review some recent additions to the tool-chest of techniques for finding compact integrand representations of multiloop gauge-theory amplitudes - including non-planar contributions - applicable for N=4 super-Yang-Mills in four and higher…

High Energy Physics - Theory · Physics 2015-05-27 John Joseph M. Carrasco , Henrik Johansson

We present an extension of the spinor integration formalism of one loop amplitudes from the double-cut to the single-cut case. This technique can be applied for the computation of the tadpole coefficients. Moreover we describe an off-shell…

High Energy Physics - Phenomenology · Physics 2012-02-14 Ruth Britto , Edoardo Mirabella

In this note, we propose a factorization formula for gauge-theory scattering amplitudes up to two loops in the high-energy boosted limit. Our formula extends existing results in the literature by incorporating the contributions from massive…

High Energy Physics - Phenomenology · Physics 2023-12-20 Guoxing Wang , Tianya Xia , Li Lin Yang , Xiaoping Ye

A number theoretic algorithm is given for writing gauge theory amplitudes in a compact manner. It is possible to write down all details of the complete $L$ loop amplitude with two integers, or a complex integer. However, a more symmetric…

General Physics · Physics 2007-05-23 Gordon Chalmers

We show that the evaluation of scattering amplitudes can be formulated as a problem of multivariate polynomial division, with the components of the integration-momenta as indeterminates. We present a recurrence relation which, independently…

High Energy Physics - Phenomenology · Physics 2015-06-05 Pierpaolo Mastrolia , Edoardo Mirabella , Giovanni Ossola , Tiziano Peraro

We argue that restricted Schur polynomials provide a useful parameterization of the complete set of gauge invariant variables of multi-matrix models. The two point functions of restricted Schur polynomials are evaluated exactly in the free…

High Energy Physics - Theory · Physics 2014-11-18 Rajsekhar Bhattacharyya , Storm Collins , Robert de Mello Koch

Supersymmetric integrands for the two-loop five-point amplitudes in ten-dimensional super Yang--Mills and type II supergravity are proposed. The kinematic numerators are manifestly local and satisfy the duality between color and kinematics…

High Energy Physics - Theory · Physics 2015-11-05 Carlos R. Mafra , Oliver Schlotterer

We examine maximal unitarity in the nonplanar case and derive remarkably compact analytic expressions for coefficients of master integrals with two-loop crossed box topology in massless four-point amplitudes in any gauge theory, thereby…

High Energy Physics - Theory · Physics 2013-10-18 Mads Sogaard

We present the two-loop virtual amplitudes for heavy-quark pair production in light quark-antiquark annihilation and gluon fusion channels, including full spin and color dependence. We use expansions around kinematical limits and numerical…

High Energy Physics - Phenomenology · Physics 2018-04-18 L. Chen , M. Czakon , R. Poncelet

We present a set of algebraic functions for evaluating the coefficients of the scalar integral basis of a general one-loop amplitude. The functions are derived from unitarity cuts, but the complete cut-integral procedure has been carried…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ruth Britto , Bo Feng

We study the three-loop four-point amplitude in ABJM theory. We determine the dual conformal invariant integrals with highest number of propagators and fix their coefficients by two-particle cuts. Evaluating such a combination of integrals…

High Energy Physics - Theory · Physics 2015-06-19 Marco S. Bianchi , Matias Leoni

We propose an approach to compute one-loop corrections to the four-point amplitude in the higher spin gravities that are holographically dual to free $O(N)$, $U(N)$ and $USp(N)$ vector models. We compute the double-particle cut of one-loop…

High Energy Physics - Theory · Physics 2020-01-29 Dmitry Ponomarev , Ergin Sezgin , Evgeny Skvortsov

One-loop amplitudes may be expanded in a basis of scalar integrals multiplied by rational coefficients. We relate the coefficient of the one-point integral to the coefficients of higher-point integrals, by considering the effects of…

High Energy Physics - Theory · Physics 2011-01-18 Ruth Britto , Bo Feng

In all mass cases needed for quark and gluon self-energies, the two-loop master diagram is expanded at large and small $q^2$, in $d$ dimensions, using identities derived from integration by parts. Expansions are given, in terms of…

High Energy Physics - Phenomenology · Physics 2011-08-17 D. J. Broadhurst , J. Fleischer , O. V. Tarasov

We present formulas for the coefficients of 2-, 3-, 4- and 5-point master integrals for one-loop massive amplitudes. The coefficients are derived from unitarity cuts in D dimensions. The input parameters can be read off from any…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ruth Britto , Bo Feng , Pierpaolo Mastrolia

We investigate the phase diagram of the complex cubic unitary ensemble of random matrices with the potential $V(M)=-\frac{1}{3}M^3+tM$ where $t$ is a complex parameter. As proven in our previous paper, the whole phase space of the model,…

Mathematical Physics · Physics 2023-02-21 Ahmad Barhoumi , Pavel M. Bleher , Alfredo Deaño , Maxim L. Yattselev

For two-loop two-point diagrams with arbitrary masses, an algorithm to derive the asymptotic expansion at large external momentum squared is constructed. By using a general theorem on asymptotic expansions of Feynman diagrams, the…

High Energy Physics - Phenomenology · Physics 2009-10-22 A. I. Davydychev , V. A. Smirnov , J. B. Tausk